ARIZONA DESCRIPTION - FORAGE VALUE - MANAGEMENT Bulletin 298 July, 1953

ARIZONA DESCRIPTION - FORAGE VALUE - MANAGEMENT Bulletin 298 July, 1953

Bulletin 298

ARIZONA

July, 1953

DESCRIPTION - FORAGE VALUE - MANAGEMENT

OUR COVER PHOTOGRAPH, by John Burnham,

Experiment Station Editor, shows range cattle grazing a thick stand of grass on the San Carlos Indian

Reservation.

CONTENTS

Grasses and grazing

Description of grasses (arranged alphabetically by scientific name)

Bibliography

Common name index

Page

1

4

101

103

FOREWORD

The kinds of plants that grow on a range affect the economy of the range livestock industry more than any other single factor. The class and number of livestock that graze the range, the type of operation, the management of the ranch, and the income received from a range livestock business are dependent on the kind of forage available. Forage is the basis of the meat, wool, hides, and other products that make the livestock industry such an important part of our national economy.

Grass is the most important kind of forage on our range lands. On most Arizona ranges it makes up the bulk of the diet of domestic livestock. It produces cheaper gains than any other feedstuff. Further, grass holds the soil in place, and allows water to seep into the soil and replenish underground reservoirs.

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The man responsible for management of the range the rancher - should know as much about the plants that occur on the range as he does about management of his livestock. This pamphlet brings together the essentials of this knowledge before the people who can use it best. It describes seventy -one range grasses important to the state of Arizona and gives their identifying characteristics, seasonal forage values, and the management practices that will maintain each grass in a productive condition.

This is an enlarged revision of Bulletin 243, Common Arizona Range Grasses, by Robert R. Humphrey, Albert L. Brown, and A. C. Everson, first printed November, 1952 and reprinted

April, 1956. This revision contains a number of grasses not included in the previous bulletin.

ARIZONA RANGE GRASSES

Their Description, Forage Value, and Management

By ROBERT R. HUMPHREY

Drawings by Lucretia B. Hamilton

GRASSES AND GRAZING

A knowledge of the functions of the roots, stems, and leaves of grass plants is of value to continued, profitable range management. Since grasses are living organisms, they are affected by all environmental factors such as temperature, moisture, light, soil, air, and other plants and animals.

These factors determine where and when a plant will grow, and how well it will survive.

A healthy perennial grass, grown under natural, normal conditions, follows a fairly definite seasonal growth cycle. It begins growth when moisture and temperature conditions are favorable, produces seed stalks, and the seed matures and is disseminated. Finally the grass stops growing and becomes dormant until favorable conditions again prevail. These visible physical changes of the plant are accompanied by changes in its internal chemistry.

As grasses mature, sugars and starches are stored in the roots, seeds, stems, and leaves. In most range grasses the reserves stored in the roots maintain life in the plant through the dormant months and enable it to resume growth in the spring. These reserves diminish very gradually during the dormant period because growth is almost at a standstill. When growth is resumed, however, the raw materials to build new leaves must come from these reserves, and they diminish more rapidly. The faster the rate of growth, the greater the drain on the food reserves.

Food reserves are drawn on and diminish as spring growth starts. This is repeated with most of our grasses as growth is resumed after the start of the summer rains. As seeds are formed and begin to ripen, food reserves are used heavily and are usually at their lowest ebb. As the seeds become ripe, plant growth slows down and food not required for seed production is again stored in the roots, stems, and leaves.

Because of this food -storage- and -depletion cycle, grasses are affected differently when grazed at different times of the year. Grazing during the dormant season has little effect on the physiology of the plant. Growth is essentially at a standstill and the bulk of the food reserves that will be used when growth is resumed are stored in the roots.

On the other hand, excessive grazing during the dormant season may affect the grasses indirectly. If grazing is too heavy, all litter may be removed, the soil may erode and much of the water that should go into the soil may be lost as runoff.

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When plants are grazed heavily early in the growing season, most of the young leaves that manufacture food may be destroyed. New growth must then come from reserve food stored in the roots. Repeated removal of the young leaves causes the root reserves to be de-

pleted and the plant will die or

become so weak that it is easily killed by drought or other adverse conditions.

Any grazing during the growth period weakens a grass to some extent because it removes the leaves which manufacture food and thus reduces the source of food reserves.

Damage is greatest, however, while the plant is making maximum growth and when the reserves are lowest, just before and during seed production. Moderate grazing when growth is beginning, or after the seeds are fully ripe, has a much smaller effect on the well -being of the plant.

Reserves built up during one year's growing season affect the vigor, seed production and yield

of the grass the following year.

Occasional season -long grazing de-

ferment allows the reserves

to build up, resulting in stronger plants the following year. Deferment also permits maximum seed production and allows seedlings to become established before being grazed.

The feeding value of the grasses follows a pattern closely related to the stage of growth. Protein con-

tent is highest during the early

growth stages and decreases as the plant matures. Crude fiber content is lowest during the early stages, but increases with approaching maturity. Digestibility decreases as protein declines and as crude fiber

increases. Phosphorus content

closely parallels protein content, being highest in the early growth stages, and decreasing later.

One of the principal goals of

range management is to develop a system of grazing that will utilize

the plants during the period of

maximum nutritive value (when

the plants are growing) without

injuring the plant.

Fortunately, most ranges in good condition support a variety of forage plants. Although all grasses follow similar trends in food reserve, the different species vary in

the time of these trends. Some

begin growth early in the spring, while others do not grow until summer. Furthermore, different grasses have different curing qualities, a fact that influences their use during dormant periods. Short grasses in general cure well, maintain a

high proportion of their protein

content throughout the year, and have a small amount of crude fiber.

Tall grasses tend to lose their protein more rapidly and show a correspondingly rapid increase in crude fiber. However, tall grasses

produce more forage than short

grasses and can be most advantageously used when their nutritive value is highest.

Each range unit presents individual problems. The rancher, however, can become acquainted with the different grasses on his ranch, their growth cycles, and their feeding value. He can devise a manage-

ment plan that will maintain or

improve his range while maintaining a high level of animal nutrition.

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EXPERIMENT STATION BULLETIN 298

Figure l.- Structure of plant. A, general habit of grass; B, rhizomes; C, stolon;

D, rhizome and stolon intergradation (X1).

In the pages to follow, it will be necessary to use a few more or less technical terms in describing some of the grasses. These terms are:

Awn

A slender, hairlike bristle borne

on the scales that surround the

seed. Awns may range from

1/4 inch or less to 8 or 10 inches.

Node

The place on a stem where the leaf is attached, usually somewhat swollen.

Internode

The portion of the stem between two successive nodes.

Spike

An unbranched, elongated flower head or seedhead.

ARIZONA RANGE GRASSES

3

Figure 2.- Crested wheatgrass (Agropyron desertorum) (X%).

CRESTED WHEATGRASS

Agropyron desertorum (Fisch.) Schult.

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Description

Growth habit: Long -lived, moderately coarse perennial bunchgrass, 2 to 3 feet tall.

Color: Bright green, curing to straw color.

Leaves: Flat, 6 to 10 inches long.

Seedheads:

11 /2 to

21/2 inch -long spikes, borne singly on the ends of the stalks. The name refers to the flat seedhead that somewhat resembles a head of wheat.

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Occurrence

Primarily in the northern part of

the state or at elevations above

5,000 feet. This grass is not native to Arizona, and generally occurs where it has been planted on rundown ranges or abandoned cropland.

Forage Value

Crested wheatgrass produces a large volume of high quality forage. It begins to grow early in the

spring, becomes dry before the

summer rains and resumes growth after the summer rains have begun.

The plants remain partly green

through the fall months unless the season is abnormally dry. When

fall rains come early the plants

again begin to grow and provide feed until covered by snow. Thus, crested wheatgrass furnishes green forage in early spring and late fall when other succulent feed is scarce.

It is highly palatable to all classes of livestock.

Because crested wheatgrass is rather coarse, it makes poor forage when dry. When green and active-

ly growing, on the other hand,

there are few grasses that are more nutritious.

Management

Crested wheatgrass is used more widely for reseeding than any other grass. It has been used successfully in the sagebrush, shortgrass, pinyon- juniper, and ponderosa pine vegetation types.

Reseeded stands generally become established during the summer. They should not be grazed during the year of seeding, nor during spring or summer of the following year. Well- established stands can be lightly grazed during fall of the second year without harm to the grasses.

Crested wheatgrass withstands

heavy grazing better than most

grasses. When closely grazed, however, livestock should be excluded

about every third year from the

time summer growth begins until the seed crop has matured.

Crested wheatgrass can be grazed to best advantage while green and actively growing. However, if cattle are fed a high -protein supplement while grazing dry wheat

grass, they will make good use of the grass.

Description

WESTERN WHEATGRASS (BLUESTEM)

Agropyron smithii Rydb.

Growth

habit: A moderately

coarse perennial sodgrass 1 to

21/2 feet tall, spreading by underground rootstocks.

Color: Blue -green when growing, curing to a washed -out straw color.

Leaves: Four to 12 inches long,

3/16 to 1 inch wide, ridged lengthwise on the upper surface, firm, tapering to a slender point.

Seedheads:

Dense, narrow, unbranched spikes 2 to 6 inches long.

Occurrence

On dry hills, moist open ground, and open pine forests in Apache,

Navajo, Coconino, Yavapai, Graham, and Pima counties from 3,000 to 7,000 feet. The grass is adapted

ARIZONA RANGE GRASSES

5

to a variety of soil conditions but makes its best growth on heavy soils where an adequate supply of moisture is available. It is tolerant of moderately alkaline soils.

Forage Value

When western wheatgrass is green it is highly palatable for all classes of livestock. The plants start growth early in the spring,

are largely dormant in the dry

period before the summer rains, then resume growth when these

rains have wet the soil. During

years with early fall

rains the

plants may produce additional feed before winter.

When cut during the late -bloom

early -dough stage western

to wheatgrass makes very good hay.

The stems are rather coarse but the protein content is high and cattle and horses eat the hay readily.

Management

Care should be taken not to graze bluestem wheatgrass too closely.

Heavy grazing reduces the forage yield and may result in death of

some of the plants. In order to

maintain or increase the stand of this grass, it should be grazed more

Figure 3.- Western wheatgrass (Agropyron smithii), plant (X1/4) and spike let (X 10).

lightly during the spring months than is usually the case on most of our rangelands. Overgrazing during the spring can be offset by reseeding adjacent run -down areas with bluestem wheatgrass or crested wheatgrass.

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Description

SLENDER WHEATGRASS

Agropyron trachycaulum (Link) Malte

Growth habit: A moderately

coarse perennial bunchgrass. The numerous flowering stems are usually 1 to 3 feet tall and are moderately leafy, particularly near the base of the plant.

Color: Flower heads tend to have a violet color which gives stands a green -violet cast. Before flowering both stems and leaves tend to have a slight bluish color.

Leaves: From 2 to 10 inches long, flat or slightly inrolled at the edges, somewhat rough to the touch.

Seedheads: Two to 8 inches long, slender, usually flattened, often purple in color. Seedheads vary widely in appearance, ranging from slender with spikelets barely overlapping to moderately thick with spikelets moderately overlapping.

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Figure 4.- Slender wheatgrass (Agropyron trachycaulum) (X).

Occurrence

In open forests and mountain

meadows at elevations from 5,000 to

12,000 feet. Where these conditions occur, slender wheatgrass may be

found from Apache to Mohave

counties on the north to Cochise and Pima counties on the south.

Forage Value

Slender wheatgrass furnishes

good to excellent feed for all classes of livestock. Because the plants are moderately coarse they are grazed somewhat more readily by cattle and horses than by sheep. Sheep do

make good use of the growing

leaves, however, taking them about as readily as they do fescues and bluegrasses.

ARIZONA RANGE GRASSES

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Management

Slender wheatgrass begins

growth as soon as the weather

warms up in the spring and, provided moisture is available, continues growth through the summer. It does not withstand as heavy grazing as grasses that produce rootstocks, but will maintain its vigor under moderate grazing more or less indefinitely. Like most grasses,

it thrives best under a deferred

grazing program that protects the plants during the growing season at periodic intervals. The poorer the condition of the range, the more essential this kind of management becomes.

Figure 5. -Cane beardgrass (Andropogon barbinodis), plant (X1

/3)

(X 10).

and spikelet

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Description

Growth habit: Coarse perennial bunchgrass 2 to 4 feet tall.

Color: Bluish green, curing to dull red or yellow.

Leaves: Wide, fairly long, occur-

ring basally and on the flower stalks. When dry they cure to a

reddish -brown color with a light colored midrib.

CANE BEARDGRASS*

Andropogon barbinodis Lag.

Seedheads: Seeds are borne in tufts of silvery hair on the end of the long seed stalks. These seed heads are usually 2 to 4 inches long and about twice as long as wide.

Other: A ring of stiff hairs occurs at the nodes.

Occurrence

At elevations of 1,000 to 5,800 feet in all counties in the state except

Apache and Mohave. It is particularly abundant along graded roadsides and banks of washes or other places where the soil has been exposed. It is also common on dry, rocky or sandy slopes. On open rangeland it occurs principally in areas of water concentration.

Forage Value

Because the grass is coarse and

the nutrients tend to leach out

after the plants are dry, cane

beardgrass is generally rated as

only fair forage. During the summer when the plants are actively growing they are grazed readily, particularly by cattle and horses.

At that time they make good feed

unless there is an abundance of

more palatable, finer -leaved species.

Management

Cane beardgrass

is most pro-

ductive when grazed during the summer when the plants are actively growing. It may be grazed during the fall and winter but the forage is of a poorer quality at that

time. When grazed during the

summer, at least a third of the seed stalks should remain ungrazed for seed production and to permit the plants to build a strong root system.

TEXAS BEARDGRASS (TEXAS BLUESTEM)

Andropogon cirratus Hack.

Description

Growth habit: Perennial bunch

grass 11/2 to 2 feet tall.

Color: Bluish -green, curing to a reddish or purplish brown.

Leaves: Slender, straight; from

1/16 to 1/4 inches wide, many of them attached on the upright stems, as well as the base of the plant.

spikelike, 1 to 21/2 inches long, not hairy.

Occurrence

Reported from Coconino, Yavapai, Graham, Gila, Pinal, Cochise,

Pima, and Santa Cruz counties. It usually grows on steep, rocky slopes at elevations of from 2,000 to 7,500 feet and is frequently asso-

ciated with oaks or pinyon and

juniper.

Seedheads: Slender, cylindrical,

* Silver beardgrass (Andropogon saccharoides) is essentially identical with cane beardgrass. All of the information given above applies also to silver beard grass.

ARIZONA RANGE GRASSES

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Figure 6. -Texas beardgrass (Andropogon cirratus) (X1).

Forage Value

Although Texas beardgrass is fine -leaved, it has hard, wiry stems.

This may account for its rather low palatability. It usually rates as only

fair forage, probably because it

generally grows among highly palatable grama grasses.

Management

Texas beardgrass is most palatable during the summer months from July into September when it is growing most actively. It should be grazed for the most part at this time. During the fall, winter and spring the plants are dry and are eaten sparingly unless there is a shortage of other feed. When graz-

ed during the growing season a

third of the seed stalks should be

left for seed production and to

assist in building up a vigorous root system.

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EXPERIMENT STATION BULLETIN 298

Figure 7.- Little bluestem (Andropogon scoparius) (X1).

LITTLE BLUESTEM

Andropogon scoparius Michx.

Description

Growth habit: A perennial erect and rather slender, with the

bunchgrass 2 to 5 feet tall with sod-

stems and leaves rather closely

forming tendencies. The plants are bunched.

ARIZONA RANGE GRASSES

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Color: Bluish -green, curing to a dark reddish- brown.

Leaves: Usually flat, rather stiff,

1/16 to 3/16 inches wide, usually 3 to 5 but sometimes as much as 10 inches long.

Seedheads: Slender, spikelike and not conspicuously hairy.

Occurrence

Reported from Apache, Navajo,

Coconino, Yavapai, Cochise, Pima, and Santa Cruz counties. It com-

monly grows in oak or juniper

woodlands, and in open pine forests or mountain meadows at elevations above 4,000 feet.

Forage Value

This grass does not rate very

high as forage. It is not very palatable and its nutrient value is rather low. Protein content has been found to be about half that of blue grama at the same stage of growth.

When cut early this grass makes hay of fair quality. It should be cut no later than the late bloom stage.

Otherwise the nutritive value and palatability of the hay will be low.

Management

Little bluestem is most productive when grazed during the months of July to September while the plants are growing. It may be grazed during the fall and winter but makes comparatively poor feed and is not readily taken when dor-

mant. When grazed during the

summer, at least one third of the seed stalks should be left for seed production and to permit the plants to build a stronger root system.

Description

Growth habit: A fine- leaved annual grass extremely variable in size. Plants may be 3 to 30 inches tall, size depending largely on available moisture. The several stems are attached at the base of

the plant and are usually wide

spreading.

Color: Yellow to bright green, curing to a straw color. Seedheads may be purple.

Leaves: Mostly short, 1/16 to 2/16

inches wide, the edges

usually rolled inward when dry.

Seedheads: Long and narrow,

consisting of many slender

branches, lying close to, and rather erect against the central stem. Each branch bears a slender seed closely

SIXWEEKS

Aristida ad

THREEAWN scensionis L.

enclosed by its surrounding scales.

Three 1/2-inch-long awns diverge from the top of these scales.

Occurrence

Widespread in the state below

6,000 feet. This grass is most abundant at elevations of about 4,000 feet,

and is not common in the drier

portions of the state where creosote bush or salt- tolerant shrubs predominate. Sixweeks threeawn makes its best growth on natural grassland sites that have been disturbed by heavy grazing or cultivation.

Forage Value

Sixweeks threeawn is one of our better annual grasses, but provides poorer forage than most perennials.

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EXPERIMENT STATION BULLETIN 298

Figure 8.- Sixweeks threeawn (Aristida adscensionis) (X1/2)

ARIZONA RANGE GRASSES

13

Although it will grow and set seed at any time of the year when mois-

ture and temperature are favor-

able, sixweeks threeawn is most prevalent during the summer and is commonly classed as a summer annual.

Management

Sixweeks threeawn may produce an abundance of feed for a short period of time. Its principal disadvantages are that it produces green feed only for a short period, and that the nutrients leach out quickly. The plants apparently lose most of their nutritive value soon after they dry.

Because of the short growing

period, ranges with an abundance of sixweeks threeawn or other palatable annuals often can be grazed to better advantage by steers rather than a breeding herd. Enough of the plants should be left in all cases to provide litter for soil and moisture conservation.

POVERTY THREEAWN*

Aristida divaricata Humb. and Bonpl.

Description

Growth habit: Perennial bunch grass 1 to 3 feet tall.

Color:

Dark green, curing to

straw -color.

Leaves: Mostly 1/16 inch wide, about 6 inches long, inrolled and spirally twisted on drying.

Seedheads: Very open, spreading branches extending at right angles from the central axis. Each seed bears three spreading, hairlike awns at its tip.

Occurrence

The distributions of these three grasses overlap to cover most of the state between elevations of

2,500 and 7,000 feet. These grasses are usually more abundant on dry

rocky hills than on fertile areas

with deep soil.

Forage Value

Poverty threeawn is generally classed as fair to poor forage. It

greens up after the spring rains

more rapidly than most grasses and is used most heavily at this time.

Figure 9.- Poverty threeawn (Aristida divaricata)

(X1/4).

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* For footnote, see next page.

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It

is grazed rather lightly after

other, more palatable grasses begin to grow.

Management

Ranges with an abundance of

poverty

threeawn may provid9

more spring grazing than ranges where this grass is not abundant.

Where this grass occurs sparsely, proper use should be based on the amount of grazing that more productive associated grasses will stand. Where poverty threeawn is to be maintained, at least one third of the seed stalks should remain ungrazed.

SANTA RITA THREEAWN

Aristida glabrata (Vasey) Hitchc.

Description

Growth habit: Small perennial bunchgrass with hard, round, wiry stems 1 to 1% feet tall.

Color: Green to gray -green almost year long.

Leaves: Short, those on the seed stalks from about 1/2 to 11/4 inches long; narrow, inrolled, not hairy.

Seedheads: Slender, several lying close to and rather erect against the central stem. Each seed bears at its tip three slender spreading awns each about 3/4 inch long. The column connecting the awns to the seed scales breaks off at slight pressure when the seed is mature.

Other: When grazed, this grass is usually clipped off evenly, 1 or 2 inches from the ground. The sharp

ends of the wiry stems feel like

bristles on a stiff brush.

Occurrence

Dry, sandy, or gravelly bajada slopes in Maricopa, Mohave, Santa

Cruz, Pinal, Pima, and Yuma coun-

ties. It is most typical of desert

shrub and grassland ranges from

2,000 to 5,000 feet.

Figure 10. -Santa Rita threeawn (Aristida glabrata), plant (X14) and spike let (X 10).

Forage Value

Although the stems are hard and

wiry and the plant is not very

* Several grasses are closely related to proverty threeawn and for grazing purposes can be considered to be identical. Two of these that are common are

Arizona threeawn (Aristida hamulosa) and spidergrass (Aristida ternipes). These three grasses may be distinguished by the following characteristics:

(1) A. ternipes has a single awn.

(2) A. divaricata has three awns at the end of a twisted awn column.

(3) A. hamulosa has three awns at the end of a straight awn column.

ARIZONA RANGE GRASSES

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leafy, it is grazed readily, particularly late in the season after most of the other grasses are dry.

Management

Santa Rita threeawn withstands rather heavy, long-continued grazing better than most of the grama grasses that commonly grow with it. Ranges with an abundance of this grass should be grazed during the spring and fall drought periods to take advantage of the seasonal green feed. The plants should not be grazed too closely. About one fourth of the seed stalks should be left at the end of the grazing season.

RED THREEAWN

Aristida longiseta Steud.

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Figure 11. -Red threeawn (Aristida longiseta), plant (X1 /3) and seed (X 1).

EXPERIMENT STATION BULLETIN 298

Description

Growth habit: Perennial bunchgrass, 6 to 15 inches tall, growing in thick clumps.

Color: Green, curing to a tan.

Old leaves from the year before usually give the growing plant a grayish green color.

Leaves: Short, rather stiff and inrolled.

Seedheads: Seed stalks are usually short and branched. The scales surrounding each seed bear three awns, 2 to 3 inches long, spreading out at right angles from the tip of the seed. The awns are red when immature.

Occurrence

Rather widespread and locally abundant in all counties except

Maricopa, Yuma, and Santa Cruz, between elevations of 3,000 and

6,000 feet. It is most common on sandy or gravelly plains and hills but becomes established on better

areas when the more palatable

grasses are grazed out.

Forage Value

Red threeawn has a low palatability rating. Because of its abundance in some areas, however, it furnishes rather large amounts of forage, particularly from late July to early September. Growth begins late in the spring but little feed is produced until the summer rains begin. During the fall and winter when the plants are dry it has very little value.

Management

Red threeawn is much less palatable than blue grama or the other grasses with which it is commonly associated. As a consequence, it increases on heavily grazed ranges at the expense of the better forage plants. Although a valuable indicator of range deterioration, red threeawn may indicate only that

the site is arid and has a well -

drained soil.

Deep soils

which support an

abundance of red threeawn can be improved by light grazing, temporary non -use, or winter grazing.

They can be satisfactorily reseeded to other grasses only by plowing or by some substitute tillage operation that gets rid of the threeawn.

PURPLE THREEAWN

Aristida purpurea Nutt.

Description

Growth habit: Perennial bunch grass in small dense clumps, 1 to

2 feet tall.

Color: Dark green curing to gray or 'straw color. In seed, the awns give the plant a purple color.

Leaves: Three to 6 inches long, small, firm, inrolled.

Seedheads: Open with slender branches that curve or droop with the weight of the seed. Seed scales have three awns that are shorter and less divergent than those of red threeawn.

Occurrence

In all counties of Arizona except

Navajo, Coconino, Greenlee, and

Yuma. It generally grows on rocky or sandy plains and slopes at elevations between 1,000 and 5,000

feet. In the lower portion of its range it

is very common along roadsides.

ARIZONA RANGE GRASSES

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Figure 12.- Purple threeawn (Aristida purpurea), plant (X%) and seed (X 1).

Forage Value

One of the poorest of our common range grasses. Palatability is low, particularly after the plants are mature.

Management

Purple threeawn should be grazed while growing most actively. As the plants green up in the spring more

than many

southwestern grasses, they can usually be grazed to advantage in March and April.

Maximum growth occurs in the summer, and ranges with an abundance of this grass will be most productive after the onset of the summer rains.

Like red threeawn, this grass

often indicates past range misuse, tending to replace the better grasses under heavy grazing. Light use, temporary non -use, or winter grazing of these areas will give the better grasses a chance to increase.

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EXPERIMENT STATION BULLETIN 298

PINE DROPSEED

Blepharoneuron tricholepis (Torr.) Nash

Description

Growth habit:

Fine -stemmed perennial bunchgrass

11/2 to

21/2 feet tall.

Color: Bright green to light gray green.

Leaves: Narrow, usually fine and short.

Seedheads: Three to 6 inches

long, slender, grayish, and loosely flowered.

Occurrence

Apache, Coconino, Mohave, Yavapai, Graham, Gila, Cochise, and

Pima counties. This grass common-

ly grows in ponderosa pine or

Douglas fir forests and open meadows at elevations of 6,000 to 10,000 feet. It is sometimes found at much lower elevations though sparsely.

rather

Forage Value

One of the best forage grasses in timbered areas. Although not as palatable as blue grama, it is con-

siderably more palatable than

mountain muhly with which it frequently grows.

Management

Because pine dropseed grows primarily on high -altitude summer ranges it should be grazed for the

Figure 13. -Pine euron tricholepis) dropseed

(X1/4).

(Blepharonmost part from July througn September. Livestock graze it sparingly when it is dormant. About one third of the seed stalks should

be left at the end of the grazing

season for seed production and to maintain plant vigor.

SIXWEEKS NEEDLE GRAMA

Bouteloua aristidoides (H.K.B.) Griseb.

Description

Growth habit:

Short -lived annual grass, 2 to 15 inches tall.

Color: Light green, curing to a straw- color.

Leaves: Thin, 1/16 to 2/16 inches wide, flat or folded, maximum length about 6 inches, sometimes with a few long hairs near the base or extending up the back.

Seedheads: Eight to 14 non -comblike spikes on the sides of slender stems. These spikes are loosely attached when dry and drop to the ground readily.

ARIZONA RANGE GRASSES

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Occurrence

Below 6,000 feet on dry mesas, washes and waste places throughout the state except in Apache and

It grows most

Navajo counties.

commonly where the original stand of perennial grasses has been depleted, or where rainfall is too low to grow perennials.

Forage Value

Sixweeks needle grama produces a small amount of poor quality forage. It yields a low volume of feed that loses most of its nutrient value about the time the seeds are shed.

The plants have a weak root system and as a consequence are easily pulled up by grazing animals. The dirt on the roots is objectionable to livestock and is one of the major reasons why this grass is rated as poor forage. In addition, it has a much shorter growing season than the associated perennial grasses.

Management

Sixweeks needle grama is pri-

marily a summer annual and is most valuable during July and

August. It grows to some extent in

the spring but seldom produces

much feed at this season.

This grass is most important on desert ranges that produce more brush than grass. In years of good rainfall it supplements the feed obtained from tobosa grass, brush and the few other perennial grasses that may be present.

Many ranchers consider annuals, either summer or winter, as short time feed that must be consumed

completely at the time they are

palatable. Although annuals are

Figure

14. - Sixweeks needle grama

(Bouteloua aristidoides), plant

(X1 /3), spike with two spikelets, and lower spikelet (X 1).

20

EXPERIMENT STATION BULLETIN 298

palatable for a short time only, the ungrazed plants are not entirely wasted. The unused plant material holds moisture on the area and increases moisture penetration, thus improving conditions so that perennial grasses may take over. In addition, close grazing of the annuals year after year will reduce

seed formation, and result in a

shortage of even this feed in later years.

SIXWEEKS GRAMA

Bouteloua barbata Lag.

Description

Growth habit:

Short -lived annual bunchgrass, 3 to 15 inches tall.

Stems spread out almost parallel with the ground from the central axis of the plant before they rise to to an upright position. This glass is often confused with Rothrock grama.

Color:

Light green, curing to

straw color.

Leaves: Few;

1/2 to 11/2 inches long, 1/16 to 2/16 inches wide.

Seedheads: Four to seven persistent, comb -like spikes are borne along the sides of the slender stems.

These are characteristic comb -like grama spikes, but are smaller than on any of the perennial gramas.

Occurrence

Almost statewide below

6,000 feet. This grama grows most commonly on open, rocky, or sandy slopes and washes, and on bare

soil areas or where other vegetation is sparse.

Figure 15.- Sixweeks grama (Bouteloua barbata) (X%).

ARIZONA RANGE GRASSES

21

Forage Value

The forage value of sixweeks, grama is low. The plants are small and produce little forage. They are short -lived, producing green feed for a short period of time, and almost worthless as forage after maturity. The plants have a weak root

system and pull up easily when

grazed, a feature that makes them objectionable to grazing animals.

M_ anagement

Ranges supporting an abundance of summer annuals and few perennial grasses reach a productivity peak within a few weeks after the first summer rains. They remain productive for one or two months, and then rapidly deteriorate.

Such ranges often can be stocked heavily during short periods when the plants are green.

SPRUCETOP GRAMA

Bouteloua chondrosioides

(H.B.K.) Benth.

Description

Growth habit: Small perennial bunchgrass, 10 to 18 inches tall.

Color: Bright green, curing to a gray- white.

Leaves: Short, narrow, and curv-

ed, but not curled as in slender grama or curly mesquite grass

Seedheads: Three to seven spikes are borne on the sides of essentially leafless stalks. These spikes are not comb -like, and are covered with very fine whitish hairs. When pulled from the stem and placed point up they rather resemble tiny spruce trees with drooping branches. They drop from the stern when mature.

Occurrence

Rather common in Cochise, Santa

Cruz and Pima counties at elevations between 2,500 and 6,000 feet.

This grama occurs most commonly

on dry rocky slopes and rolling

desert grasslands with fine -textured soils.

Forage Value

One of the most palatable grasses of the state. Because of its small size, it produces less forage than most of our perennial grasses.

Management

Sprucetop grama is most palatable during the summer rainy season. It cures exceptionally well, re-

taining a high percentage of its

nutritive value when dry. Because of the curing qualities of this grass,

ranges where it is abundant are

well suited for use during the dormant season.

When grazed during the growing season at least one third of the seed stalks should be left for seed production and to maintain plant vigor. When grazed after the plants have matured, no more than one fourth of the seed stalks need remain.

22

EXPERIMENT STATION BULLETIN 298

Figure 16.- Sprucetop grama loua chondrosioides) (X1 /3).

(Boute-

SIDEOATS GRAMA

Bouteloua curtipendula

(Michx.) Torr.

Description

Growth habit: Medium -size perennial bunchgrass, 15 to 30 inches tall, or occasionally taller. This is

the largest and coarsest of the

grama grasses.

Color: Bluish -green, sometimes with a purplish cast, especially in

the spring, curing to a reddish

brown or straw color.

Leaves: Coarser than the rest of the gramas, straight, and comparatively stiff, mostly basal.

Seedheads: Ten to thirty small, non -comb -like spikes are borne along the side of each central seed stalk. These spikes drop when mature, leaving a long, zigzag stalk.

Occurrence

Over most of the state on rocky open slopes, woodlands, and forest

openings up to an elevation of

about 7,000 feet. Although not common below 2,500 feet, it does extend considerably lower than this where moisture conditions are favorable.

Forage Value

This is one of our most important range grasses. Although not as palatable

as some of

the smaller gramas, i.e., blue or slender, it is more palatable than many grasses other than the gramas. It produces

a much greater volume of feed

than blue grama, and this tends to make up for its slightly lower palatability. It remains green later in the fall and usually begins growth

in the spring before the other

gramas. It cures well, and maintains a fairly high feeding value throughout the year.

ARIZONA RANGE GRASSES 23

Figure 17.- Sideoats grama (Bouteloua curtipendula), plant (X1 /2) and spikelet

(X 1).

Management

Sideoats grama is not as resistant to grazing as blue grama. This may

be because sideoats stays green

longer and is grazed for a longer period. Many ranges that formerly produced large amounts of this grass now produce little. Reduced forage production, carrying capacity, and cattle gains have resulted.

Sideoats is a normal component of most Arizona grassland ges, and these ranges are not in excellent condition without an abund-

24

EXPERIMENT STATION BULLETIN 298

ance of the grass. It lengthens the grazing season and increases forage production, in addition to providing variety in the feed.

Sideoats

will return to most

ranges under good management.

Practices that will bring the grass back include moderation in grazing, occasional summer rest, and brush control.

BLACK GRAMA

Bouteloua eriopoda Torr.

Description

Growth habit: A tangled perennial sodgrass, forming bunches 12 to 24 inches tall.

Color: Grayish green, curing to gray. Stem bases are covered with a fine white fuzz.

Leaves:

Narrow, less than

1/8 inch wide; 1 to 5 inches long, inrolled, wavy.

Seedheads: Four to five, occasionally more, comb -like spikes are borne on the sides of the seed stalks.

These spikes are very narrow, and do not drop away at maturity. The grass grows in large patches, spreading by above -ground stems that droop to the ground and take root.

Occurrence

Throughout most of the state between 3,500 and 6,000 feet. It thrives

best in open grasslands on dry,

gravelly or sandy soils. Although originally much more abundant than it is today, this grass is still fairly common over much of its range.

Forage Value

Black grama is one of our best and most nutritious grasses. It produces an abundance of forage that remains palatable and nutritious throughout the year. Although less palatable than most gramas during the summer growing season, it cures well and provides excellent fall, winter, and spring feed. The

Figure 18. - Black grama (Bouteloua eriopoda) (X1/4).

stems are usually green even when the plants are not actively growing, a feature that makes this grass particularly valuable as winter forage.

Management

Black grama is readily damaged by heavy grazing during the summer growing season. During the fall, winter and spring, when it is

ARIZONA RANGE GRASSES

25

most valuable as forage, it is less easily harmed. Ranges on which black grama is a major component of the vegetation should be reserved for winter range if possible.

As black grama is a sod grass it spreads largely by runners. Since production of viable seed is low, it is difficult to re- establish once it has disappeared from a range.

SLENDER GRAMA

Bouteloua filiformis (Fourn.) Griffiths

Description

Growth habit: Small, fine -stemmed perennial bunchgrass, 12 to 18 inches tall.

Color: Bright green, curing to yellow or gray.

Leaves: Very narrow, 1/16 to

2/16 inch wide, borne at the base of the plant. As they mature they become very curly.

Seedheads: Three to seven or

more hanging non -comb -like spikes

are borne along one side of the

flower stalk. These are not hairy as in sprucetop grama. They drop

from the plant at maturity.

Occurrence

Mohave, Greenlee, Graham, Pinal, Cochise, Santa Cruz and Pima counties below 5,000 feet. It is most common on sandy or rocky soils on plains and foothills.

Forage Value

Slender grama is one of the most palatable range grasses in the state.

Like most of the grama grasses, it cures well and is moderately palatable even when dry.

Management

Slender grama stands up well under moderate grazing. It withstands close grazing when this is not continued for too long a period.

Figure 19. -Slender grama (Bouteloua filiformis) (X1/3).

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EXPERIMENT STATION BULLETIN 298

BLUE GRAMA

Bouteloua gracilis (H.B.K.) Lag.

Description

Growth habit: A low- growing perennial bunchgrass that fre-

quently grows thick enough to

form an open sod. Usually 6 to 12 inches tall, but the seedstalks occasionally reach a height of 4 feet or more.

Color: Grayish -green, curing to gray or straw yellow.

Leaves: Fine, of variable length, sometimes curled or inrolled and borne close to the ground.

Seedheads: Seeds are borne on two stalk.

(occasionally one, three or four) comb -like spikes per seed

These heads are typical comb -like grama spikes, straight or slightly curved and usually hairless. They remain attached to the seed stalk at maturity.

Occurrence

Native in all the counties of the state, but occurs only sparsely in the southwestern portion. It occurs on open rocky slopes, plains, forest openings, and mountain meadows, mostly between 4,000 and 8,000 feet.

Forage Value

Blue grama is probably the best known Arizona range grass and is one of our most valuable forage plants. The fine, palatable leaves are low in fiber and high in protein when green. Blue grama cures well and may retain up to 50 per cent of its nutritive value when dormant.

It is thus an excellent winter, as well as summer, feed.

Under favorable conditions, blue grama produces abundant forage.

Many Arizona ranges, however, even where this grass is abundant, do not provide these conditions. On some the soil is compacted, on others, as in the higher mountains,

temperatures are low, and blue

grama produces very little feed.

Under these conditions, it is an inferior forage plant, not because of reduced palatability or nutritiousness, but because it produces less forage than other grasses would under the same conditions.

Figure 20. - Blue grama (Bouteloua gracilis) (X1/4).

ARIZONA RANGE GRASSES

27

Management

Blue grama is exceptionally resistant to long- continued, heavy grazing. Although more palatable than many grasses that grow with it, blue grama may remain as the sole occupant of an area because of its ability to withstand grazing.

In spite of its ability to persist under heavy use, blue grama benefits from the same management that benefits other dryland grasses.

Occasional grazing deferment during the growing season, moderate grazing, and proper distribution of stock are good management prac-

tices for blue grama or for any

other grass.

Blue grama frequently becomes sodbound, particularly on fine -textured soils or after heavy grazing and trampling. When this occurs, forage production may be increased by opening the sod with a chisel or

eccentric disc to permit greater

moisture penetration.

HAIRY GRAMA

Bouteloua hirsuta Lag.

Description

Growth habit: Small perennial bunchgrass 1 to 2 feet tall, closely resembling blue grama.

Color:

Bluish -green, curing to gray or straw- color.

Leaves: Fine, narrow, confined to the base of the plant.

Seedheads: Two, occasionally

Dne, three, or four comb -like spikes are borne on the leafless flower stalk. These spikes are persistent and are covered with hairs. They are seldom straight, and are sometimes coiled into a complete circle.

There will usually be a slender

needle -like point that extends beyond each separate spie.

Occurrence

Reported from all counties except

Apache, Coconino, Maricopa, and

Yuma. It grows mostly from 4,000 to 6,500 feet but occasionally at lower elevations.

Forage Value

Hairy grama is one of the most

nutritious of the grama grasses, comparing very favorably with

blue grama.

It

cures well and,

Figure 21. - Hairy grama (Bouteloua hirsuta) (X%).

28

EXPERIMENT STATION BULLETIN 298

though not as nutritious as blue

grama after curing, it still is one of

the most palatable Arizona

range grasses.

Management

Ranges with a large amount of hairy grama should in most cases be used primarily for fall, winter, and spring grazing. Although the grass is most palatable and nutritious during the summer grazing

season, heavy use at this time

weakens the plants and reduces the stand. Further, the curing quality of this grass makes it better suited

than most grasses for use when

dormant. Adjacent areas, where grasses that cure poorly predominate, should be grazed during the growing season.

ROTHROCK GRAMA

Bouteloua rothrockii Vasey

Description

Growth habit: Short -lived, perennial bunchgrass, 10 to 18 inches tall. The plant is more erect than sixweeks grama, an annual grass with which it is often confused.

Color:

Light green, curing to

straw color.

Leaves: Small, fine and confined to the base of the plant.

Seedheads: Three to eight comb

like spikes are produced on the side of the slender seed stalks; these

remain attached to the plant at

maturity.

Occurrence

Dry rocky hillsides and sandy mesas in Mohave, Yavapai, Graham, Pinal, Cochise, Pima, and

Santa Cruz counties, mostly between 2,300 and 5,500 feet. This grass was once quite common on the edge of the desert, but much of it has been grazed out. It has be-

come more common on better

rangelands as the more palatable grasses have disappeared.

Forage Value

Rothrock grama is palatable when actively growing, though less nutritious than most perennial grama grasses at the same stage of growth. This grass does not cure

Figure 22.- Rothrock grama (Bouteloua rothrockii) (X Y4).

well and rates only fair in palata-

bility and nutritive value when

dry.

ARIZONA RANGE GRASSES

29

Management

Ranges where this is the principal grass should be grazed primarily

during the summer months

when actively growing. On most grassland ranges Rothrock grama will be replaced by better grasses under proper range management.

It is very susceptible to drought, and its abundance may fluctuate widely from year to year, depending on weather conditions.

FRINGED BROMEGRASS

Bromus ciliatus L.

30

Figure 23.- Fringed bromegrass (Bromus ciliatus) (X1).

EXPERIMENT STATION BULLETIN 298

Description

Growth habit: An erect perennial, rather slender bunchgrass with a well -developed root system.

Stems are usually 11/2 to 3 feet tall.

Color: Bright green in moderate shade or in the open, ranging to light green in dense shade.

Leaves: One -quarter to 1/2 inch wide, generally 6 to 10 inches long, essentially flat, somewhat rough and hairy on the upper surface.

Seedheads: Four to 12 inches

long. Individual spikes are drooping on slender stems.

Occurrence

Reported from Apache, Coconino,

Yavapai, Graham, Gila, Cochise, and Pima counties, generally at elevations of 6,000 to 10,000 feet.

This is largely a grass of forested areas and does best in open timber stands or in clearings.

Forage Value

This is one of the most palatable grasses in the state. Although it seldom grows in thick stands, it is sufficiently widespread to be an important forage species on many of our forest ranges. Cattle, horses, and sheep, as well as deer and elk, graze this grass readily throughout the summer. Sheep are particularly fond of the developing seedheads.

Management

Because it

is so palatable this

bromegrass is frequently grazed too closely. To get the most out of it year after year, about one -third of the seed stalks should be left every year. Because this is one of the most sought -after grasses on many summer ranges,

it would

benefit from deferment about every third year.

Description

RED BROME (Foxtail brome, Foxtail chess)

Bromus rubens L.

heads mature they become reddish

brown to purplish.

Growth habit: A spring annual, tufted bunchgrass, usually 8 to 20

inches tall but often less when

growing on arid, shallow -soil sites.

The several to numerous stems

spread from the base of the plant.

Color: Light green when growing; when mature the plants cure to a light straw yellow topped by purple to red -purple seedheads.

Leaves: About 2 to 4 inches long,

flat, sparsely covered with fine

rather fuzzy hairs.

Seedheads: One and a half to three inches long by about half as wide; dense, borne erect on the ends of unbranched stems, with a kind of bottle -brush appearance. As seed-

Occurrence

Open hillsides and woodland or chaparral areas. Particularly common on ranges where the original perennial grass cover has deteriorated. This grass appears to be still spreading in Arizona and has been reported from Coconino, Mohave,

Yavapai, Gila, Maricopa, Pinal and

Pima counties.

Forage Value

Red brome is grazed to some extent during its short growing period but is largely ungrazed after the seedheads mature. The plants are shallow rooted and pull up when grazed. The dirt that clings to the

ARIZONA RANGE GRASSES

31

Figure 24. -Red brome

(Bromus rubens)

(X1/3).

roots is objectionable to grazing animals and accounts in some measure for the plant's low palatability.

Management

Where red brome produces most of the feed on an area it should be heavily grazed early in the spring to make maximum use of available

32 forage before seedheads mature. On ranges that receive 14 inches or more of rain, where red brome or other annuals make up most of the feed, the possibility of artificial reseeding should be looked into. Most of the ranges that support this grass once grew perennial grasses and can be made to do so again.

EXPERIMENT STATION BULLETIN 298

CHEATGRASS

Bromus tectorum

L.

Description

Growth habit: Annual, generally germinating in the fall and maturing the following spring, or germinating during the summer rainy season and maturing by early fall.

Extremely variable in height, ma-

ture plants ranging from 5 or 6

inches to 2 feet.

Color: Light green when growing -often purple at maturity and generally a light straw yellow after the plants have died.

Leaves: Two to 4 inches long,

flat, and covered with soft fine

hairs.

Seedheads: Open, with the individual flower heads drooping on slender stems.

Occurrence

Primarily in the northern part

of the state, being reported from

Navajo,

Coconino, and Yavapai counties, but is extending its limits southward.

This weedy annual,

which was introduced from Europe, is most abundant along highways and railroads but is rapidly spreading into adjacent pinyon - juniper and ponderosa pine rangelands.

Forage Value

During years of favorable precipitation cheatgrass is a valuable forage plant. Like all annuals, however, it is entirely dependent on the current year's precipitation for growth and may be almost worthless in drought years. In good years the plants produce an abundance of feed but this tends to be washy.

Analyses of cheatgrass hay indicate

Figure 25.- Cheatgrass (Bromus rum) (X%).

tectothat it has only one -fifth the digestible protein content of average alfalfa hay.

Management

Because cheatgrass matures

rapidly and loses much of its food value on drying, grazing should be

ARIZONA RANGE GRASSES

33

Figure 26.- Feather fingergrass ( Chlorfis virgata) (X%).

concentrated during the few weeks when it is most actively growing.

Unless very heavy grazing is continued for several years, enough seed normally matures to assure a good stand the following year.

34

FEATHER FINGERGRASS

Chloris virgata Swartz

Description

Growth habit: A weedy, annual bunchgrass with weak, spreading stems and a shallow root system.

EXPERIMENT STATION BULLETIN 298

Color: Light green when growing; light straw color when dead.

Leaves: Flat or folded, thin, and rather weak, with few or no hairs.

Seedheads: Several slender feathery branches 1 to 3 inches long, radiating fingerlike from the end of a slender, erect stem.

Occurrence

A common roadside and wasteland weed occurring usually below about 5,500 feet elevation. It occurs in all counties of the state, and is one of the first grasses to become established on bare soil.

Forage Value

Because of its local abundance this grass is valuable as forage in some locations. Like other annuals, however, it produces abundantly only after good rainfall seasons or where it receives extra moisture as runoff from adjacent areas. Although feather fingergrass is fine leaved and soft -stemmed, its palatability is low. Livestock will graze it but much prefer the perennial gramas when available.

Management

Feather fingergrass grows rapid-

ly, and, like most of our annual

grasses, appears to set seed abundantly. For these reasons it can be grazed rather closely without harming the next year's crop. Very often the best management consists of reseeding stands of this grass with good perennials.

BERMUDA GRASS

Cynodon dactylon (L.) Pers.

Description

Growth habit: A low- growing sodgrass that above -ground

spreads by both

and below -ground stems.

Color: Variable green to yellow green, curing to straw color after frost.

Leaves: Usually short, flat, and narrow.

Seedheads: Seeds are borne on four or five very narrow branches that spread fingerlike from the tip of short leafless stalks.

Forage Value

Bermuda grass is primarily valuable as an irrigated pasture grass, but frequently provides abundant feed in cienegas or along stream banks. It is relished by all classes of livestock, and where moisture is available, it grows through the spring, summer, and fall months.

Animals make their best gains on

Bermuda grass when it grows intermixed with bur clover or some other legume.

Occurrence

Throughout the state but most common in the southern portions and in irrigated areas, along stream banks, or where moisture accumu-

lates. This is the principal lawn

grass in southern Arizona.

Management

Bermuda grass is hard and wiry and should be grazed rather closely. It stands up exceptionally well under long- continued moderately h e a v y use.

Irrigated pastures should not be grazed while being

irrigated or while the ground is

still soft and muddy. Periodic fer-

ARIZONA RANGE GRASSES

35

Figure 27.- Bermuda grass (Cynodon dactylon), plant (X Vs) and spikelet (X 10).

tilization once a year with a highforage yields which otherwise will nitrogen fertilizer will maintain generally decrease.

Description

ORCHARDGRASS

Dactylis glomerata L.

Growth habit: A long -lived perennial bunchgrass sometimes growing in large circular clumps from i to 4 feet tall.

Color: From rather dark green in full sunlight to light green in moderate shade.

Leaves: Young leaf blades are sharply folded but open out flat and about 1/8 to Y4 inch wide as they mature. Leaf edges when rubbed toward the base have a sandpaper like feel.

Occurrence

Used rather commonly as an irrigated pasture grass but also seeded

36

EXPERIMENT STATION BULLETIN 298

Figure 28.- Orchardgrass (Dactylis glomerata) (X%).

ARIZONA RANGE GRASSES

37

sometimes in timbered areas after fire, on logging roads, skid trails and other depleted sites. Usually found at altitudes above 6,500 feet; reported from Navajo, Coconino,

Mohave, Graham and Gila counties, but because of reseeding may occur elsewhere. More shade tolerant than most grasses.

Forage Value

Highly palatable and producing abundant forage, particularly early in the season. Rated high as a hay or pasture plant, particularly when interplanted with Ladino or some other clover.

Management

Orchardgrass should be moderately grazed, particularly during the spring when it is growing most actively. Although a good forage

producer, it will not withstand

long- continued heavy use. When irrigated it should be rather heavily fertilized with nitrogen for maximum production.

DESERT SALTGRASS

Distichlis stricta (Torr.) Rydb.

Description

Growth habit: A low- growing, rather harsh sodgrass with tough, scaly, creeping rootstocks.

Color: Blue -green to gray -green.

Leaves: Sharp, folded or inrolled for part of their length; rather stiff.

Seedheads: Erect from the creeping rootstock, borne on short stems

usually 4 to 15 inches tall. The

heads frequently become yellowish as the seeds mature.

Occurrence

Most common in Apache, Navajo,

Coconino, Pinal, Yuma, Cochise, and Pima counties. Usually found on subirrigated alkali flats or on alkaline soil near springs or stream beds. In Arizona it rarely occurs above 6,000 feet.

Forage Value

Although rather harsh, desert saltgrass is usually rated as fair to good forage because it

stays green when most other grasses are dry.

Management

Growing, as it does, on subirrigated soils, desert saltgrass can generally be used to best advantage during the spring and fall drought periods when most of the upland

grasses are dry. As it generally grows along streams or around

springs, seeps, or other local wet spots, this grass is usually grazed as long as it is green. For best production, however, it should not be grazed closely the year around.

Description

WOOLY BUNCHGRASS

Elyonurus barbiculmis Hack.

Growth habit: A per e n n i al

bunchgrass generally about 18 inches to 2 feet tall.

Color: Rather light green, curing to a dark straw yellow.

Leaves: Long, narrow and inrolled; usually without hairs but some-

times with a few soft spreading

hairs on the upper surface.

38

EXPERIMENT STATION BULLETIN 298

Figure 29.- Desert saltgrass (Distichlis stricta), plant

(X1/2) and spikelet (X 10).

ARIZONA RANGE GRASSES

39

Seedheads: Slender, round, unbranched; seeds without awns;

heads about 2 to 4 inches long,

dense and light green or silvery.

Occurrence

Common locally in the southern part of the state, occurring largely in Cochise, Pima, and Santa Cruz counties. It is generally restricted to rocky hillsides in stands of oak or juniper.

Forage Value

This grass makes fair

forage when green but poor when dry.

Management

Wooly bunchgrass usually grows

intermixed with more palatable

grama grasses. Grazing pressure

that does not harm the grama

grasses will likewise not harm the woolly bunchgrass. Close grazing of bunchgrass, on the other hand, generally indicates that the range

as a whole has been much too

heavily grazed.

SPIKE PAPPUSGRASS

Enneapogon desvauxii Beauv.

Description

Growth habit: A slender- stemmed perennial bunchgrass, 4 to 18 inches tall. Plants are usually rather stem my with few broad leaves. Individual stems tend to bend at the joints.

Color: Light green to gray -green leaves; the flower stalks sometimes purplish.

Leaves: Rather sparse, slender, about 1/16 inch wide, rolled inward or folded, with very fine soft hairs.

Seedheads: Densely flowered spikes that are highly variable in length but usually range from 1 to

40

Figure 30.- Woolly bunchgrass (Elyonurus barbiculmis) (X1).

2 inches long by about 1/2 to 3/4 inch broad; gray -green color; bristly looking.

Occurrence

Common throughout most of the state below 6,000 feet, but partic-

EXPERIMENT STATION BULLETIN 298

ularly abundant in desert and semi

desert areas in the upper southern desert shrub and desert grassland areas. This grass is known to occur in all counties of the state except

Apache and Yuma.

Forage Value

Moderately palatable, more so during the summer rainy season than in the spring. The plants are most palatable before the numerous hairy seed heads develop. The stems often remain alive as late as November, which makes this grass valuable for late fall grazing.

Management

This grass seems to be rather

short -lived for a perennial. However, it is a prolific seeder and reestablishes rapidly and abundantly during seasons of good rainfall.

When intermixed with other

grasses these are usually more palatable than pappusgrass. As a re-

sult this grass is grazed rather

lightly until late in the season, when it is partially cured and can withstand heavier use. Like all grasses, however, it can be killed out by continued overuse.

BOER LOVEGRASS

Eragrostis chloromelas Steud.

Description

Growth habit: A vigorous -growing, long -lived perennial bunch grass introduced from South Africa.

Mature plants are typically 1i{2 to 3 feet tall, growing from dense many stemmed and many -leaved crowns.

Color: Blue- green.

Leaves: Basal leaves pi- vide most of the forage. These ai ` 24 to 36

Figure 31. -Spike pappusgrass (Ennea pogon desvauxii) (X112).

ARIZONA RANGE GRASSES

41

42

Figure 32. -Boer lovegrass (Eragrostis chloromelas)

(X1

/a).

inches long, narrow, flexible, with curled tips and are somewhat rough to the touch. Their blue -green color gives the entire plant a bluish cast.

Seedheads: Eight to 10 inches long, open and distinctly diamond shaped. Seeds are extremely small, running about 3 million per pound.

Occurrence

Boer lovegrass occurs primarily on depleted desert grassland ranges

where it has been artificially

seeded. It is not well adapted to alkaline soils, seeming to thrive best on essentially neutral sites where annual precipitation is 13 inches or

EXPERIMENT STATION BULLETIN 298

more. Winterkilling limits the use of this grass to areas where winter temperatures normally do not drop to zero Fahrenheit.

Forage Value

Boer lovegrass rates high both in palatability and volume production.

It produces abundantly both in the spring, when there is usually a deficiency of green feed, and in the summer. Even when an abundance of other feed is available, however, cattle make good use of Boer love grass. It is also taken readily in the fall after native grasses have cured.

Management

Boer lovegrass, like most non -native grasses seeded on depleted ranges, can be grazed to best advantage when planted as extensive stands that provide the bulk of the

feed in a pasture. Otherwise, it

tends to be grazed out as a result of heavy spring use. The ability of this grass to produce green feed in

the spring makes it particularly

well suited to use in areas that tend to be deficient in green spring feed.

Because of its heavy summer production and high palatability, on the other hand, it is valuable for summer and fall grazing. Like most grasses, it should be moderately grazed in pastures that are stocked every year. Consistent heavy use will result in deterioration of the

stand and in a reduction of the

range carrying capacity.

WEEPING LOVEGRASS

Eragrostis curvula (Schrad.) Nees.

Description

Growth habit: A vigorous -grow-

ing perennial bunchgrass with

abundant leaves coming from a coarse, dense, basal crown. When moisture is adequate, plants reach a height of 2 to 5 feet.

Color: Light green.

Leaves: Twenty -four to 48 inches long, drooping, slender, tapering to fine hair -like brownish threads.

Bases of the densely clustered

young leaves are purplish; the leaf blades as a whole are light green.

As they age they tend to become somewhat fibrous and tough.

Seedheads: Eight to 12 inches long, open and somewhat drooping.

Branches bearing the seedheads are tall and slender, occurring singly or in pairs. Flowers are small and numerous and produce minute seeds that number about 11/2 million per pound.

Occurrence

Weeping lovegrass is an introduction from South Africa and occurs in Arizona largely where seeded on depleted or burned -over ranges. It appears to be well adapted to areas where precipitation is 17 inches or more, but will probably not withstand temperatures that fall much lower than 10 °F. below zero.

Forage Value

Weeping lovegrass has a reputation in its native Africa of being a good forage producer well liked by

ARIZONA RANGE GRASSES

43

Figure 33.- Weeping lovegrass (Eragrostis curvula)

(X1/3).

cattle. Studies in Oklahoma have indicated that it is most palatable in the spring when actively growing but may be grazed very little during the summer when actively blooming and when other forage is available. Arizona observations have shown that this grass is frequently preferred above many na-

tive grasses, particularly in the

spring. On most Arizona ranges where it is adapted, it apparently should be rated as a highly productive, moderately palatable species.

Management

When weeping lovegrass is not grazed, the coarse, rank growth is unattractive to livestock. Grazing, therefore, should be heavy enough to keep the surplus growth removed but not heavy enough to deplete the

44 EXPERIMENT STATION BULLETIN 298

stand. On burns reseeded to this grass grazing should be initiated the summer after seeding. This recommendation is made on the assumption that a satisfactory stand was established the season the area was seeded. These ranges may be

moderately grazed from early

spring to late fall without harm to the grass. As burned ranges where weeping lovegrass is adapted usually support a mixture of scrub oak and other shrubs, grazing about one year after the fire in this manner permits use of the abundant new growth on the shrubs. Erosion is not increased on most ranges under

this kind of a grazing program

where the stocking rate is moderate.

WILMAN LOVEGRASS

Eragrostis superba Peyr.

Description

Growth habit: A moderately

leafy, summer -growing perennial bunchgrass growing erect from a moderately vigorous and sparsely branched base to a height of about

3 feet.

Color: Light green.

Leaves: Twelve to 18 inches long, rather flat and thin, not wiry as in weeping lovegrass.

Seedheads: Six to 10 inches long on the end of erect stems. The individual spikelets are numerous and flattened, somewhat resembling rattlesnake rattles. The large, conspicuous seedheads are rather ornamental.

Occurrence

Wilman lovegrass occurs only where seeded in revegetation tests and primarily at elevations below about 4500 feet in central and southern Arizona. It is not adapted where temperatures drop below 10-

15 degrees Fahrenheit nor where mean annual precipitation is less than about 14 inches. This grass thrives best on medium- textured, deep soils that are neither strongly acid nor strongly alkaline.

Forage Value

Wilman lovegrass is moderately palatable, being more so than Lehmann lovegrass, and rather comparable in this respect to sideoats grama. It is particularly well liked by rabbits, a feature that makes establishment difficult in areas where these animals are abundant.

Like the other introduced love grasses, Wilman grows well during early spring and produces more spring forage than most of the native perennial grasses.

Management

When Wilman lovegrass is seeded

on depleted ranges it should be

sown as a pure stand over areas sufficiently extensive to constitute the bulk of the feed produced in a given pasture. Otherwise, it will probably be grazed out and the expense and effort of seeding wasted. Stands should not be grazed until at least the second summer growing season.

Although the plants are not unduly sensitive to grazing pressures, use

ARIZONA RANGE GRASSES

45

Figure 34.- Wilman lovegrass (Eragrostis superba) (XV3).

should be moderate and no heavier native than would be given well managed grama.

grasses such as

sideoats

PLAINS LOVEGRASS

Eragrostis intermedia Hitchc.

Description

Growth habit: A moderately

coarse bunchgrass, 2 to 3 feet tall,

with a

rather open, somewhat spreading growth habit.

Color: An intermediate shade of green when growing; after maturity the plants dry to a light straw yellow.

Leaves: Long and slender, rang-

46 EXPERIMENT STATION BULLETIN 298

Figure 35.- Plains lovegrass (Eragrostis intermedia), plant (X1 /3) and spikelet

(X 10).

ing from 4 to 10 inches long by about 1/8 inch wide; edges usually somewhat rolled toward the upper side of the leaf. Leaf blades are smooth on the lower surface but rather rough above.

Seedheads: Open, broadly pyramid -shaped with numerous branches that branch again; 8 to 16 inches long and 6 to 12 inches wide.

Occurrence

Widespread in the upper desert

grassland and oak woodland of

ARIZONA RANGE GRASSES

47

Gila, Maricopa, Cochise, Pima, and

Santa Cruz counties, and has been found in Coconino and Yavapai counties. This grass was originally

much more abundant than it

is today. Its reduction is probably the result of long- continued grazing.

Some of the best stands in the state are at Fort Huachuca.

Forage Value

In spite of its coarseness, plains lovegrass is a good forage species.

Prior to 1910, when plains love grass was still abundant, Professor

Thornber wrote that it was eaten by livestock wherever they could

get at

species to be grazed. He noted also that

it, and that even on the

steeper slopes it

was the

first

it was one of the earliest

grasses to

start growth in

the spring.

Management

Because of its palatability and early greening habit, plains love grass is often overgrazed in early spring. Where possible, it should be deferred during July and August about every third year. Because of its early spring value, ranges where this grass still remains should be managed to maintain or increase it.

LEHMANN LOVEGRASS

Eragrostis lehmanniana Nees

Description

Growth habit: Perennial bunch grass 18 inches to 2 feet tall.

Color: Bright green, curing to dull yellow.

Leaves: Two to 6 inches long, up to 1 /16 inch wide, rather stiff.

Seedheads: Open, spreading; 3 to

6 inches long, each of the branches tipped with a small gray seedhead.

In flower, the numerous, feathery seedheads give fields of the grass a gray color.

Occurrence

An introduction from South Africa that has become well established on some ranges and along roads, principally in Graham, Pima, and

Cochise counties. This grass has proved to be best adapted to elevations from 3,000 to 4,500 feet.

Forage Value

The greatest forage value of this grass lies in its ability to remain green late in the fall, and to green

48 up early in the spring. Even though growth is rapid during the summer months, the plants are grazed lightly at that time except where

there is a lack of native forage.

During the spring months it provides good forage and is taken in preference to the dry native grasses.

Management

Lehmann lovegrass has proved to be the grass best adapted to reseeding southern Arizona ranges.

Although easy to establish on adapted sites, it is a special -purpose grass rather than a remedy for all range ills. Because it is most valuable in the spring, this grass should be planted in large, manageable units adapted to spring use.

Although this grass is not readily damaged by grazing, care should be given to any Lehmann lovegrass seeding. Reseeding is expensive,

and the grass must be properly

EXPERIMENT STATION BULLETIN 298

Figure 36.- Lehman lovegrass (Eragrostis lehmanniana) (X1).

handled if it is to repay the investment. The plants should become well -established before grazing.

This usually requires two growing seasons.

Once established, the planting should be moderately grazed during the spring. Then,

after the native range has made

sufficient growth, livestock should be removed from the lovegrass so

that it can recover and produce

seed during the summer. A program of this sort should insure a long -lived stand of grass.

ARIZONA RANGE GRASSES

49

STINKGRASS

Eragrostis megastachya (Koel.) Link.

Description

Growth habit: An annual, erect to prostrate bunchgrass, 4 to 24 inches tall.

Color: Light green to gray -green.

Leaves: Thin, flat, up to

1/4 inch wide, largely from near the base, with numerous, small, glandular depressions.

Seedheads: Erect, dark gray green to tawny, 2 to 8 inches long.

Occurrence

A common roadside weed below

6000 feet recorded from all counties except Apache, Navajo, Mohave and Maricopa but may occur in these counties also. Particularly common in heavy bottomland soils.

Forage Value

Has little value as forage. Like most annual grasses, stinkgrass has a short growing season and produces a low volume of feed. Because of the weak root system the plants

tend to pull up when grazed. In

part because of this they rate low in palatability.

Management

Areas supporting little other vegetation except stinkgrass should be reseeded to perennial forage species

Figure 37.- Stinkgrass megastachya)

(X3/4).

(Eragrostis adapted to local climatic and soil conditions. Control of stinkgrass may be necessary prior to seeding to reduce competition and permit establishment of the perennials.

ARIZONA FESCUE

Festuca arizonica Vasey

Description

Growth habit:

A

with a large number

clustered stems. The bunchgrass of densely wiry seed

50 stalks on mature plants are usually

2 to 3 feet tall.

Color: Gray -green to blue -green.

Leaves: Slender, 10 to 20 inches

EXPERIMENT STATION BULLETIN 298

Figure 38.- Arizona fescue (Festuca arizonica), plant

(X%/s) and spikelet (X 10).

long, stiff and somewhat wiry with inrolled edges.

Seedheads: Usually about 3 to 6 inches long with several spreading branches.

Occurrence

One of the principal grasses in the evergreen forests of the state at elevations of 7,000 to 10,000 feet. It is most abundant in the north -central and northern counties, occurring rather sparingly southward.

Forage Value

This is one of the better forage grasses of northern Arizona. Although relatively palatable, it is not taken as readily as blue grama

ARIZONA RANGE GRASSES

51

or Junegrass. It is a larger grass than either of these, and produces a large amount of forage. The fact that the plants are at least partly green during spring, summer and fall adds to their value and palatability.

Management

Arizona fescue stands up well under moderate grazing, but tends to go out under close grazing much more quickly than blue grama with which it is sometimes associated.

Because of this inability to pro-

duce well under heavy use,

it should not be heavily grazed year after

year during the summer

growing season.

SHEEP FESCUE

Festuca ovina L.

Description

Growth habit: A vigorously

growing, many- stemmed, strongly rooted bunchgrass, usually with several erect, slender flower stalks that are commonly 4 to 12, though occasionally as much as 24 inches tall.

Color: Light green to gray -green.

Leaves: Numerous, mostly from

the base of the plant;

slender,

rather wiry, 2 to 5 inches long,

rough when rubbed from the top toward the base.

Seedheads: Two to 4 inches long, usually rather open and somewhat interrupted, generally rather onesided with ascending side branches.

Occurrence

Sheep fescue occurs in Arizona only in Apache and Coconino counties and at elevations above 7,000 feet. It is particularly abundant in the open parks on the North Kaibab, but tends to be common in similar open park -like areas at high elevations throughout its range. This grass is not particularly shade tol-

erant and consequently occurs

sparsely in timber stands.

Forage Value

Sheep fescue produces a bulk of the forage for all classes of livestock in most areas where it occurs.

This is in large part because it usually makes up a large percentage of the vegetation. Although moderately palatable, it does not seem to have the palatability in Arizona that it does in other parts of the West.

The leaves are hard and wiry when they mature, a characteristic that undoubtedly affects the degree to which they are grazed. The highly nutritious seedheads, on the other hand, are readily grazed and con-

tribute markedly to

the forage value of this grass.

Management

Sheep fescue stands up better than many grasses under long -continued, moderate grazing. It should not be grazed in the spring until the seedheads begin to show. When grazed by cattle the grazing load should be such as to permit summer long use before the range will have been properly utilized. This will permit seed setting and will enable the plants to set aside a suf-

52

EXPERIMENT STATION BULLETIN 298

ficient reserve of carbohydrates to maintain a strong root system. Badly deteriorated ranges where this grass could be dominant should be protected for at least the first half of the growing season and lightly grazed the balance of the summer until a good range- condition level has been reached.

TANGLEHEAD

Heteropogon contortus (L.) Beauv.

Description

Growth habit: A coarse, perennial bunchgrass 1 to 3 feet tall.

Color: Bright green, curing to a distinctive orange- brown.

Leaves: Broad, 2/16 to 5/16 inches wide; creased down the middle, and clasping the flattened stem at the base.

Seedheads: Spikelike. Each seed has a sharp -pointed base and a long,

coarse awn. At maturity, these

seeds and their awns are black and twist around each other to form a tangled mass.

Occurrence

Primarily on rocky slopes and canyons from 1,000 to 5,500 feet in all counties except Apache, Navajo, Coconino, Greenlee, and Mari

copa. Because of its low palata-

bility this grass usually persists

longer on heavily grazed ranges than most of the perennial grasses.

Forage Value

Tanglehead begins growth early

in the spring and at this time is

readily eaten by cattle and horses.

It becomes coarse and less palata-

Figure 39. - Sheep fescue (Festuca ovina) (X1/2).

ARIZONA RANGE GRASSES

53

Figure 40.- Tanglehead (Heteropogon contortus), plant (X%/s) and seed (X 10).

ble as it matures and is rated as

poor forage on a year -long basis.

Because of its coarseness it has

little value for sheep.

54

Management

Areas in which tanglehead occurs intermixed with other grasses must be managed on a basis of the forage

EXPERIMENT STATION BULLETIN 298

as a whole. Tanglehead will be

lightly used on year -long ranges because of its low palatability. If it were completely used, most of the other forage plants would be overgrazed.

Ranges on which tanglehead makes up a major part of the for-

age should be used during the

spring months to take advantage of the early growth of the grass.

Tanglehead has received much attention as a grass for reseeding the more arid portions of the desert grassland, particularly the low rocky ridges. It is one of the easiest grasses to establish under conditions of low rainfall. The low seed production, however, and the difficulty of cleaning the long -awned

seeds make its use in extensive

seeding programs impractical.

CURLY MESQUITE

Hilaria belangeri (Steud.) Nash

Description

Growth habit: A small,

fine leaved sodgrass up to 1 foot tall.

Color: Bright bluish -green when growing, curing to almost white.

Leaves: Flat, very fine, 3 to 5 inches long, becoming tightly curled as they cure.

Seedheads: Spikelike, borne at

the end of slender stalks rarely

over 8 inches long. Seedheads consist of groups of chaffy seed which fall at maturity, leaving a zigzag stalk.

Occurrence

Locally common in all counties except Apache, Navajo, Mohave,

and Yuma. It usually grows in

heavy soils on dry, rocky hillsides

or in swales between 3,000 and

6,000 feet.

Forage Value

Curly mesquite is one of the most

palatable and nutritous

of the southwestern grasses. Its high graz-

ing value and growth habit are

indicated by one of the common names - southwestern buffalo grass.

Like buffalo grass and blue grama, curly mesquite provides good for-

age when actively growing and

when cured. As with grasses generally, its forage value is highest when green. The principal shortcoming of curly mesquite is its small size and consequent small volume of forage produced.

Management

Curly mesquite stands up well under grazing. The plant spreads readily by short, curved runners

that take root and develop new

plants where they

touch the

ground, or by seed. Under heavy grazing, it is one of the last perennial grasses to go out. Solid stands

of the grass sometimes indicate

long- continued heavy use.

Even though curly mesquite is

highly palatable and nutritious,

pure stands are seldom as product-

ive as the original mixed stand.

The original mixed stand produced

a greater volume and variety of

forage. Furthermore, by the time the other grasses have been grazed out, grazing pressure and trampling will have reduced forage pro-

ARIZONA RANGE GRASSES

55

Figure 41. -Curly mesquite (Hilaria belangeri), plant (X%) and spikelet cluster

(X 10).

duction of curly mesquite.

A range with an abundance of curly mesquite should be managed to maintain or bring back high producing associated grasses, and

to keep these grasses and curly

mesquite in excellent vigor. As a guide to the range condition, the trend should be indicated by highvolume producing grasses, rather than by curly mesquite. When the other grasses are abundant or increasing, management is sound; when they are largely lacking or

decreasing, the s t o eking load should be lightened or grazing should be deferred

occasionally during the growing season.

56

EXPERIMENT STATION BULLETIN 298

GALLETA

Hilaria jamesii (Torr.) Benth.

Description

Growth habit: A coarse sodgrass

with a bunchy habit of growth,

usually 1 to 2 feet tall.

Color: Dull blue- green, curing to a light straw yellow.

Leaves:

Stiff, straight,

1 wide; edges usually inrolled.

to 2

inches long 1/16 to 3/16 inches

Seedheads: Spikes up to 31/2 inches long, composed of groups of chaffy seed. Spikes drop at maturity, leaving a zigzag stalk.

Occurrence

On dry,

sandy plateaus and broad, open valleys or uplands in

Apache, Navajo, Coconino, and Mohave counties at elevations from

4,500 to 7,000 feet.

Forage Value

Because of its abundance this grass is one of the most important forage plants in the northeastern

part of the state. When actively

growing, it is classed as good to excellent feed for cattle and horses and fair for sheep. When dry, it is almost worthless for all classes of livestock.

Management

Galleta should be grazed during

the summer while it is growing

since it has almost no value when dry.

The grass becomes coarse when it is not grazed and for this

reason should be grazed rather

Figure 42. - Galleta (Hilaria jamesii)

(X%).

heavily. It appears to stand up rather well under close grazing but, like most grasses, should be rested occasionally during the growing season when grazed closely year after year.

Hilaria

TOBOSA mutica (Buckl.) Benth

Description

Growth habit: A coarse peren-

nial bunchgrass 1 to 2 feet tall,

growing from a coarse scaly rootstock. Stems spread out at the base, then curve inward at the top, giv-

ARIZONA RANGE GRASSES

57

58

Figure 43.- Tobosa (Hilaria mutica)

(X1/2).

EXPERIMENT STATION BULLETIN 298

ing each bunch a pointed appearance. Stems are not woolly. Tobosa grows over a wide range of climatic conditions and shows considerable variation in form, depending on conditions under which it grows.

In the drier portion of its range it becomes very coarse while at higher elevations, where moisture is more plentiful, the plants are much smaller and finer.

Color:

Dull bluish -green when growing, curing to gray.

Leaves: Up to 6 inches long, stiff and harsh, hairless.

Seedheads: Spikes composed of groups of chaffy seeds. These drop at maturity, leaving a zigzag seed stalk.

Occurrence

Locally common in Yavapai,

Gila, Mohave, Graham, Yuma, Cochise, Santa Cruz, and Pima counties at elevations from 2,000 to 6,000 feet. In the lower or more southern parts of its range, tobosa grows on fine -textured soils in swales that receive runoff water. Farther north or at the higher elevations it occurs typically in fine -textured soils on dry rocky hillsides or mesa tops.

Forage Value

The forage value of tobosa grass varies from good during the summer months when it is green, to very poor during the winter months, when it becomes harsh and wiry and loses most of its value as forage. Forage value during the summer is also variable, depending

upon the amount of old growth

remaining on the plants.

If old

growth is profuse, cattle will not graze the plant unless forced to it.

Because of its coarseness tobosa

provides no better than poor to

fair feed for sheep even while

growing. It has no value for sheep after drying.

Management

Tobosa is fairly resistant to grazing, probably because of its coarseness and low palatability. It should be used during the summer when it is green and has its highest forage value. A rotation developed in southern New Mexico utilizes tobosa grass areas during the summer and black grama during the winter. This has maintained the black grama range in top condition and has not materially injured the tobosa.

Best quality tobosa grass is obtained by eliminating as much of the old growth as possible, which

may be done by heavy grazing,

burning or haying. Heavy grazing will keep the old growth down, but may injure the stand because of close use during the growing season, trampling, or both. Burning every third or fourth year during

late winter or early spring has

been satisfactory on many areas.

Grazing should be deferred on

burned areas until a satisfactory

growth has been made after the

fire. On the Jornada Experimental

Range in New Mexico, the grass

has been cut for hay with good

success. If cut at the proper time tobosa yields about a quarter ton

of high quality prairie hay per

acre, more than enough to pay for the operation.

In many desert areas, the swales that produce tobosa grass deter-

ARIZONA RANGE GRASSES

59

mine the carrying capacity of the area. Practices that will maintain or increase water spreading will

increase the stand of tobosa on

such sites.

Gullies frequently start in tobosa flats, draining off water that should be stored in the soil. In order to prevent death of the grasses, gullies should be checked as soon as possible. Erection of dams with spreader wings frequently increases the

area flooded and thus promotes growth of tobosa forage. These

dams will also supply stock water

during times of stress, a much

needed improvement desert ranges.

on many

BIG GALLETA

Hilaria rigida (Thurb.) Benth.

Description

Growth habit: A large, coarse, almost woody, perennial bunch grass, 1 to 3 feet tall. Stems are woolly at the base.

Color: Dull bluish -green when growing, curing to gray or a dirty white.

Leaves: Coarse, nearly straight, and fairly wide, the edges sometimes rolled. Leaves attached both at the base of the plant and along

the upright stems that bear the seedheads. Leaf blades may be

partly covered with short, light, woolly fuzz.

Seedheads: Spike composed of groups of chaffy seed which drop at maturity to leave a zigzag seed stalk. Spikes are mostly 11/2 to 4 inches long.

Occurrence

On deserts, plains, sand dunes and rocky hillsides in Mohave,

Yavapai,

Pinal,

Maricopa, and

Yuma counties up to an elevation of 4,000 feet.

This plant grows

mostly on clay soils that receive extra runoff during the summer rains. It may be common also on sand dunes in the hot, dry southwest corner of the state.

Forage Value

Big galleta makes fair forage for

cattle and horses when actively

growing. When dry it has no forage value.

Management

Ranges where this grass provides most of the feed should usually be grazed during the early spring and summer months while the plants are growing. As it occurs rather extensively in the western part of

the state where winter rainfall

usually exceeds summer rainfall, it may make most of its growth in these areas in the spring.

Annuals such as filaree and Indian wheat often occur in abundance on big galleta ranges. During the occasional years when these plants are abundant, ranges should be heavily stocked for a short period to take advantage of this feed.

Some use will be made of the big galleta but this grass should not be used as an index of the carrying capacity during these years.

60

EXPERIMENT STATION BULLETIN 298

Figure 44. -Big galleta

(Hilaria rigida)

(X1/2).

ARIZONA RANGE GRASSES

61

JUNEGRASS

Koeleria cristata (L.) Pers.

Description

Growth habit: A medium to small perennial bunchgrass 1 to 11 feet tall.

Color: Bright green when grow-

ing in good light; light green in

moderate shade.

Leaves: One and one -half to 5 inches long; narrow, flat, sharp pointed and ridged and rough on the upper surface; arising largely from the base of the plant.

Seedheads: Seed stalks numerous, slender, and 1 to 11/2 feet tall.

The seedhead is a dense, cylindrical shiny spike 11 to 6 inches long,

% inch wide, tapering at both ends.

Occurrence

Moderately abundant in all coun-

ties in the state except Yuma at

elevations from about 4,000 to 9,000 feet. Although this grass grows on

nearly all soil types, it

is most

abundant and makes the

best growth on sandy sites. The grass rarely forms pure stands but is one of the most widely distributed of all western grasses.

Figure 45. - Junegrass (Koeleria cris tata) (X1).

Forage Value

Junegrass is rated as good forage for all classes of livestock. It greens up earlier in the spring than most

grasses and is

often overgrazed early in the season. It grows most actively and produces the bulk of its feed during the summer after the rains begin.

62

Management

Care must be taken not to overgraze Junegrass in the spring when it first greens up. When the plants are grazed during the growing sea-

son at least a third of the seed

stalks should be left for seed production and to make certain that the vegetative parts of the plants will not be grazed too closely.

EXPERIMENT STATION BULLETIN 298

Figure 46. -Green sprangletop (Leptochloa dubia), plant (X1) and spikelet (X 10).

GREEN SPRANGLETOP

Leptochloa dubia

(H.B.K.) Nees

Description

Growth habit: A coarse, erect, few- stemmed perennial b u n c hgrass, usually 2 to 3 feet tall.

Color:

Bluish -green to rather dark green; the portion of the leaf blade that encircles the stem often tinged with purple.

Leaves: Usually

1/8 to slightly less than

1/4 inch wide, either flat or folded at the midrib but not inrolled at the edges.

Seedheads: A single central stem with from two or three to as many as fifteen slender, flexible drooping branches. These branches are usually from

11/2 to 5 inches long and are well separated on the end 4 to

8 inches of the stem.

ARIZONA RANGE GRASSES

63

Occurrence

From Greenlee to Yavapai county and south into Mexico; has not been reported north of the Mogollon Rim or from Mohave or Yuma counties. Generally grows at elevations from 2,500 to 6,000 feet on open upland sites.

Forage Value

Because of its coarseness, green sprangletop is only moderately palatable.

It generally grows somewhat sparingly interspersed with other grasses and is not a particularly valuable forage species.

Management

Because green sprangletop is not

an important source of feed on

most areas, ranges supporting this grass should usually be managed primarily to maintain or improve the associated forage species.

64

Figure 47.- Wolftail (Lycurus phleoides), plant (X%) and spikelet (X 10).

EXPERIMENT STATION BULLETIN 298

WOLFTAIL (TEXAS TIMOTHY)

Lycurus phleoides H.B.K.

Description

Growth habit: A small perennial bunchgrass, 1 to

11/2 feet tall. Similar

in vegetative appearance to

blue grama or hairy grama with which it is often associated.

Color: Grayish -green, curing to a grayish -straw color.

Leaves: Mostly in a basal clump, fine, usually with white margins.

Seedheads: Narrow terminal

spikes 1 to 3 inches long and

1/4 inch in diameter. Both common names refer to this timothy -like seedhead that resembles a wolf's tail.

Occurrence

In all counties except Mohave,

Maricopa, and Yuma, at elevations of 4,000 to 7,000 feet. It is found occasionally as pure stands, but usually grows interspersed with other grasses. It is most abundant on rocky, open slopes in the upper desert grasslands, chaparral, and oak woodland.

Forage Value

Wolftail provides good forage for all classes of livestock. Although slightly less palatable than blue grama it is better than most of the coarser range grasses. Growth occurs largely in summer after the rains begin, but the plants do green up early in the spring.

Management

Because wolftaìl greens up early, ranges where this grass is abundant

can be used to advantage in the

spring. The summer growth on this and associated grasses also makes it well- suited to summer grazing.

When grazed during both spring and summer, use should be light enough to assure setting of a good crop of seed.

BULLGRASS

Muhlenbergia emersleyi Vasey

Description

Growth habit: A large, coarse perennial bunchgrass 2 to 4 feet tall.

Color: A rather light green when growing, curing to a light gray.

Leaves: Long, slender, usually folded and confined largely to the base of the plant.

Seedheads: Flowers are borne in a long plume at the end of a long, slightly leafy stalk. Plumes are 4 to 20 inches long, dense, but rather loose.

Occurrence

Rather common on hillsides at elevations from about 3,500 to 6,500 feet in all counties except Navajo,

Greenlee, Maricopa, and Yuma. It is found most often growing on rocky slopes and ledges in open stands of oak or pinyon and juniper.

Forage Value

Because of its coarseness, bull

grass has a low palatability for all classes of livestock. It is taken most readily by horses and has almost no value for sheep. Cattle will graze

it lightly when growth is most

active but show a distinct preference for other associated grasses.

Management

B u 11 g r a s s usually grows on ranges that are grazed during the spring, summer, and fall. As other,

ARIZONA RANGE GRASSES

65

Figure 48.- Bullgrass (Muhlenbergia emersleyi) (X1).

more palatable grasses provide ed to maintain these grasses. If use most of the forage on these areas, is heavy on bullgrass, the better the stocking rate should be designgrasses will be killed out.

MOUNTAIN MUHLY

Muhlenbergia montana (Nutt.) Ilitchc.

Description

Growth habit: A dense -growing, moderately large bunchgrass that

flowers after the soil has been

moistened by summer rains. The plants are usually about 1 to 2 feet tall.

Color: Light green; plants often appear purplish when seeds are ripe.

Leaves: inrolled, twisted.

Thin, often somewhat and generally a little

66

EXPERIMENT STATION BULLETIN 298

Seedheads: About 3 to 8 inches long, loose and one -sided.

Occurrence

The commonest grass in the state at high altitudes in stands of pine and Douglas fir. An abundant species from 5,000 to 6,500 feet and one of the dominant grasses in the open grasslands between McNary and

Springerville. It grows in moder-

ately dense shade but produces

most abundantly in the open.

Forage Value

Mountain muhly is a valuable forage plant because of its abundance rather than because of high palatability. Although it produces large amounts of herbage it is one of the least palatable of the high altitude grasses in the state. It is

grazed most readily during the

early summer when the plants are actively growing.

Management

Mountain muhly is usually the principal grass in the dry forested range between the meadows, and is less palatable than the meadow plants. This, and the natural concentration of stock around water, almost always results in overuse of the meadows and much lighter use of the upland areas between.

Most efficient use of many of our high mountain ranges could be obtained by fencing off the meadows.

In this way stock would be forced

Figure 49.- Mountain muhly (Muhlenbergia montana), plant (X%) and spike let (X 10).

to make fuller use of the dry upland areas and the meadows would have a chance to recover from their typically depleted condition. This would result in an increase in the number of stock that could be run on both meadows and upland.

BUSH MUHLY

Muhlenbergia

Description

Growth habit: A large, weak s t e m m e d, fine, wiry perennial bunchgrass. Stems are leafy for their entire length, branched, bent

at the joints, and knotty at the

(HOE GRASS) porteri Scribn.

base. When ungrazed, the plants form a tangled leafy mass 1 to 3 feet high and 11 to 3 feet across.

Color: Purplish -green, curing to an over -all buff. Some stems re-

ARIZONA RANGE GRASSES

67

Figure 50. -Bush muhly (Muhlenbergia portent), plant (Xi/s) and spikelet (X 10).

main a dull green throughout the year.

Leaves: Short, fine, up to 1/s inch wide.

Seedheads: Fine, many- branched, loosely drooping, purplish. During good years the very numerous seedheads give the entire plant a cobwebby appearance.

68

Occurrence

Dry mesas and rocky slopes from

2,000 to 6,000 feet in all counties of the state except Apache county.

This was formerly one of of the

most abundant and important

grasses of southern Arizona, but is found now largely as individual

plants under the

protection of shrubs.

EXPERIMENT STATION BULLETIN 298

Forage Value

Bush muhly is highly palatable

to all classes of livestock. It remains green most of the year if

sufficient moisture is available. On conservatively grazed ranges it is utilized chiefly between December and July, but because of its ability to remain green yearlong, it does provide some feed every month of the year.

Management

Where possible this grass should be allowed to set a full crop of seed during the summer growing season at least every second or third year.

Deferment of grazing during July and August every year is recommended on run -down ranges. As there are few stands of this grass that have not been overgrazed this recommendation applies to most areas where it grows.

DEERGRASS

Muhlenbergia rigens (Benth.) Hitchc.

Description

Growth habit: Large, coarse, perennial bunchgrass, 2 to 5 feet tall.

Color:

Cures to a gray straw

color.

Leaves: Coarse, 4 to 20 inches long, the edges usually inrolled, growing almost entirely from the base of the plant.

Seedheads: Flower head is a long and narrow spike, usually 4 to 15 inches long and 1/4 to 3/8 inch in diameter.

Occurrence

Open wooded slopes at elevations from 3,000 to 7,500 feet in all counties except Navajo, Mohave, Greenlee, Maricopa, and Yuma. Most typ-

ical in open stands of oaks and along gravelly or sandy stream

beds.

Forage Value

Because of its coarseness, deer

grass makes poor feed for all classes of livestock. It is most palatable

for horses and least for sheep.

Cattle will graze deergrass while the plants are growing most rapidly but show a distinct preference for other grasses.

Management

Deergrass usually grows on ranges that are grazed during the spring, summer and fall. As other more palatable grasses provide most of the forage on these areas, the stocking rate should be designed to maintain these grasses. If use is heavy on deergrass, the better grasses will be grazed out.

RINGGRASS (RING MUHLY)

Muhlenbergia torreyi (Kunth.) Hitchc.

Description

Growth habit: A low- growing, fine -leaved, fine -stemmed sodgrass that tends to grow in rings, These are caused by the center dying out

as the plant enlarges. The rings may range in size from several

inches to a few feet across.

Color:

Green to

bluish- green, reddish or purplish. The red or pur-

ARIZONA RANGE GRASSES

69

70

Figure 51.- Deergrass (Muhlenbergia rigens) (X1/2).

EXPERIMENT STATION BULLETIN 298

ple cast is given the plants by the numerous seed heads.

Leaves: Very numerous, forming a crisp, curly cushion, slender to the point of being threadlike, curved rather like a bow and inrolled at the edges; from 1 to 11/2 inches long.

Seedheads: Usually from 2 to 9 inches long, profusely spreading with fine, almost hair -like branches.

The flowerheads are usually purplish even before maturity. Seeds are small and one of the seed scales is tipped with a fine awn that may be twice as long as the seed.

Occurrence

Widespread throughout much of the pinyon -juniper and grassland range in the central and northern part of the state. An abundance of this grass is almost always a sign of a run -down range. Occasionally it may indicate a poor site.

Forage Value

Even when ringgrass is young and growing rapidly its palatability is low. As the plants mature palatability drops almost to zero.

Because of their low palatability and small size, ringgrass plants have very little value as forage.

Management

Ranges with ringgrass should be managed to restore the better grasses. Continued attempts to obtain even a moderate amount of feed

from the ringgrass will in time

drive out all of the desirable spe-

Figure 52. - Ringgrass (Muhlenbergia torreyi) (X1/2).

cies and result in consistent weight losses in the animals being grazed.

Ranges with an abundance of this grass should be rested during the summer rainy season at least every other year until the vigor and density of the better species has clearly improved.

SPIKE MUHLY

Muhlenbergia wrightii Vasey

Description

Growth habit: A perennial bunchgrass that may have short underground stems or rootstocks. Indi-

vidual bunches are often rather

open and may be as much as one to

ARIZONA RANGE GRASSES

71

Figure 53. -Spike muhly

(Muhlenbergia wrightii) (X1).

two feet in diameter. Flowering

stalks are usually no more than one foot tall but may grow to a

height of two feet.

Color: Light green except for the seedheads, which are gray to blackish, and the leaf sheaths, which are purplish near the stem joints.

Leaves: Generally 3 to 6 inches long, narrow almost to the point of being threadlike,

1/8 inch wide or

72 less, very finely tapering and sharp pointed.

Seedheads: Somewhat resembling timothy but gray -black in color, narrower and the head often partly or entirely separated into distinct segments. Heads may be as much as 4 inches long; they are rarely over 3/s of an inch wide.

Occurrence

Spike muhly occurs at moderately

EXPERIMENT STATION BULLETIN 298

high to high altitudes in Arizona, commonly between elevations of

5,500 to 9,000 feet. It grows most abundantly in meadows or parklike

openings of forested areas in

Apache, Navajo, Coconino, Yavapai,

Gila and Pima counties.

Forage Value

This is one of the most palatable grasses in that portion of Arizona where it occurs. It is grazed readily by all classes of domestic livestock and withstands moderate grazing without appreciable damage.

Management

On good- to excellent- condition ranges with an abundance of spike muhly the principal management practice needed is to see that the plants are not heavily grazed. They

will stand moderate use indefi-

nitely, particularly if seed is allowed to mature and to replace the

plants that die. On deteriorated

ranges deferment through the summer growing season every 2nd to

5th year or very light grazing every year will be required to build the range back to top production.

INDIAN RICEGRASS

Oryzopsis hymenoides (Roem. & Schult.) Ricker

Description

Growth habit: A leafy perennial bunchgrass 1 to 2 feet tall.

Color: Rather dark green when growing, light straw -color when cured.

Leaves: Numerous, slender, firm and tightly inrolled; 6 -15 inches long; they may be as long as the flower stalks.

Seedheads: Six to 12 inches long, very open and widely spreading.

Each seedhead has several branches, each of which in turn divides.

Seeds are borne singly at the ends of wavy branches. The seeds are

round, black, and covered with

short white hairs.

Occurrence

Most common in the northern part of the state at elevations of

3,500 to 6,500 feet in Apache, Navajo, Coconino, Mohave, Yavapai, and

Pima counties. Although well adapted to sandy soils Indian ricegrass is by no means restricted to such areas. It frequently grows associated with shadscale and winterfat and is able to withstand moderate amounts of alkali.

Forage Value

This grass is highly palatable to all classes of livestock. It cures exceptionally well and is valued as a winter feed for cattle, sheep, and horses. The seeds, which stay on

the plant, are large and high in

protein. They are responsible to a considerable degree for the value of the grass as a winter feed.

Management

Indian ricegrass should be lightly grazed during the spring to give the nutritious seeds a chance to develop. If the plants are grazed close early in the season, seed production as well as vigor of the plants will be reduced.

Areas supporting an abundance of this grass should be reserved for winter use. Grazing during this season alone, when the plants are

dormant, will tend to maintain

ARIZONA RANGE GRASSES

73

Figure 54.- Indian ricegrass (Oryzopsis hymenoides), plant (X'/3) and spikelet

(X 10).

these ranges in top condition. Inbe grazed more closely when dordian ricegrass, and all grasses, can mant than when actively growing.

BLUE PANIC

Panicum antidotale Retz.

Description

Growth habit: A vigorous perennial bunchgrass with coarse stems or canes 5 to 7 feet in height, growing from an extensive root system and thick, short, bulbous rhizomes.

The stems have an open, branching habit, producing several heads at irregular intervals.

Color: Pale green to bluish green.

Leaves: Long, flat, 7 to 12 inches long, rather abundant.

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EXPERIMENT STATION BULLETIN 298

Figure 55. -Blue panic (Panicum antidotale)

(X1/3).

Seedheads: Loose, open, numerous, 8 to 12 inches, erect to slightly

drooping on

the numerous branches.

Occurrence

Blue panic is a native of India that was introduced into the United

States from Australia.

It occurs primarily at moderate to low ele-

vations in central and southern

Arizona where seeded on irrigated or flooded areas. In the lower portions of the state where blue panic does not winterkill, precipitation is too low to permit growth without

ARIZONA RANGE GRASSES

75

irrigation. With consistent or even occasional irrigation, this grass produces an abundance of forage. It is moderately tolerant to alkali.

Forage Value

In spite of its coarseness, blue panic is a valuable forage producer.

This is in part because it yields a large volume of forage, in part because it is highly palatable. Maximum green forage yields are ob-

tained from May into

October, though the dry grass provides fair feed during the late fall and winter

after it has cured. Blue panic is

most palatable for cattle and sheep.

Horses relish the hay but don't

seem to care much for the green forage.

Management

The key to maximum forage production with this grass seems to be heavy nitrogen fertilization and irrigation adequate to keep the plants actively growing. In irrigated pastures rotation of grazing animals to prevent excessive trampling of wet ground and to give the plants a regrowth period is essential. Pastures should be rotated to avoid grazing the growing plants more closely than to an 8 -10 inch stubble height.

Protein content of blue panic

compares favorably with that of alfalfa. Chemical analyses run in

Texas indicated a protein content of between 11.5 and 14.5 percent.

Description

HALL'S PANIC GRASS

Panicum hallii Vasey

Pinal, Cochise, Pima and Santa

Cruz counties.

Growth habit: A rather small, tufted perennial bunchgrass with numerous leaves.

Color: green.

Light green to bluish

Leaves: Often clustered at the base of the plant, thin and curling with age to resemble papery shavings. Leaf blades are usually up to

1/4 inch wide and 2 to 8 inches long.

Seedheads: Flowers and seeds are borne on erect, branched, slender stems. The seeds, which are

scattered along the seedhead

branches, have the appearance of small nutlets.

Occurrence

Widely scattered and locally abundant through much of the

desert grassland from about 2500 to 7500 feet. Has been found in

Coconino, Yavapai, Greenlee, Gila,

Forage Value

Highly palatable, and for this rea-

son, rather inc..ned to be over-

grazed even though associated grama grasses are properly utilized.

Because of the general softness and thinness of the leaves, and the tendency for some green leaves to be present much of the year, Hall's panic grass remains moderately to highly palatable even after plants have cured.

Management

Unless used in reseeding programs that plant pure stands over extensive areas, few ranges can be managed to maintain this grass. It usually makes up a minor portion

of the perennial grasses on any

range. Because of its palatability it

76

EXPERIMENT STATION BULLETIN 298

Figure 56.- Hall's panic grass (Panicum hallii) (X1/a).

may be damaged by a degree of grazing that does not harm the associated grasses. The forage produced by these other species should not be sacrificed to maintain the panic grass. As the panic grass goes

out the others should fill in the

spaces left vacant so that total pro-

duction in the area will not be

lessened.

ARIZONA RANGE GRASSES

77

Figure 57. -Vine mesquite (Panicum obtusum), plant (X%) and spikelet (X 10).

VINE MESQUITE

Panicum obtusum

H.B.K.

Description

Growth habit: A perennial viney type of sodgrass. Runners form on top of the ground. These are round, wiry and may be as much as 10 feet long. The nodes of these runners

78

are swollen and densely

hairy.

Because of the sod growth habit, stands of the grass are often rather dense.

Color: Light bluish -green, curing first to a reddish -straw color

EXPERIMENT STATION BULLETIN 298

and finally to a gray tan.

Leaves: Flat to somewhat inrolled at the edges; hairless or very

nearly so; up to

8 inches long; about 1/4 inch wide.

Seedheads: Generally

3 to

5 inches long. Each seedhead consists of two to six 1 -inch long branches, closely appressed to the main stem.

The large, blunt seeds are borne along these branches.

Occurrence

In all counties except Coconino,

Graham, Pinal, and Maricopa at elevations ranging from 1,000 to

6,000 feet. This grass usually grows in swales, mud flats, lowlands with fine -textured soils, and along drainages that are irrigated at times by flood waters. It extends up into the lower ponderosa pine forest but is more common at slightly lower elevations.

Forage Value

Vine mesquite provides fair for-

age for

all classes of livestock while green, but becomes coarse and unpalatable after maturity. It rates excellent as an erosion control plant.

Management

Vine mesquite should be grazed during the summer while actively

growing because the stems and

leaves are coarse and lose much of their palatability on drying. As this grass grows in areas that are sub-

ject to erosion, it should not be

heavily grazed. Light grazing gives the runners an opportunity to grow and permits the plants to spread.

PAPPUSGRASS

Pappophorum mucronulatum Nees.

Description

Growth habit: An erect, finely tufted, hairy, perennial bunchgrass, roughly 2 to 3 feet tall when growing on good sites with adequate rainfall, but commonly smaller.

Color: Gray -green to light green.

Leaves: Flat or folded, thin, up to 1/4 inch wide, often inrolled on drying.

Seedheads: Four to

10 inches long, cylindrical, hairy- appearing because of the numerous bristles, tan to gray- white.

Occurrence

Cochise and Pima counties in the desert -grassland and desert -shrub types from 2500 to 4000 feet. Fre-

quently grows intermixed with

grama grasses.

Forage Value

Pappusgrass has moderate to

good palatability for cattle and

horses. However, as it is not abundant on most ranges it is usually not rated as a particularly valuable forage producer.

Management

Pappusgrass may be maintained on a range under the same intensity of grazing that will maintain associated grama grasses. On deteriorated ranges it will recover most rapidly under a program of deferment and rotation. These ranges

ARIZONA RANGE GRASSES

79

Figure 58.- Pappusgrass (Pappophorum mucronulatum) (X1/3).

need not be closed to grazing yearduring the summer growing sea long but only for about two months son.

80

EXPERIMENT STATION BULLETIN 298

MUTTONGRASS

Poa fendleriana (Steud.) Vasey

Description

Growth habit: A medium -size bunchgrass usually 1 to 2 feet tall.

Basal diameter of individual bunches may range from less than an inch to about a foot.

Color: Usually pale bluish -green, particularly late in the season; may

tend toward a bright green in

rapidly growing plants early in the season.

Leaves: Generally 2 to 12 inches long, growing largely from a basal clump; stiff, usually folded or with inrolled edges.

Seedheads: One to 4 inches long, rather densely flowered and compact; generally erect rather than nodding.

Occurrence

Common on well- drained soils in open woodland and forested areas throughout the state at elevations of 5,000 to 11,000 feet.

Figure 59. - Muttongrass (Poa f endleriana), plant (X%) and inflorescence

(X 1).

Forage Value

One of the better forage grasses in the higher portions of the state; particularly valuable as summer sheep feed.

Muttongrass starts

growth in late winter or early

spring and provides an abundance of good early feed. It rates as excellent for cattle and horses and good for sheep. The foliage cures rather well, and rates as fair fall forage, though less palatable than during late spring and early summer.

Management

Because of the forage value of this grass, ranges with moderate or abundant amounts of it should be managed to improve or maintain the stand. At least one -fourth of the year's production of seed heads should be left by the time growth begins the following summer. Rundown ranges should not be grazed during July and August in alter-

nate years to give the plants a

chance to set seed and to increase vigor.

ARIZONA RANGE GRASSES

81

KENTUCKY BLUEGRASS

Poa pratensis L.

Description

Growth habit: A low -growing sodgrass spreading from under-

ground rootstocks. The erect

flowering stems are

1

to 3 feet

tall, numerous and slender. When moisture and light are adequate, the plants form a dense sod.

Color: Dark shiny green.

Leaves: Mostly attached to the

stems near the ground, smooth,

shiny, 2 to 7 inches long, 1/16 to

3/16 inch wide, with a boat -shaped tip.

Seedheads: Pyramid- shaped, 1 to

4 inches long, open. Lowermost branches slender, spreading, usually five in a whorl. Base of individual flowers has cobweb appearance.

Occurrence

Throughout the state except in the low, drier areas. A common lawn and pasture grass at higher elevations.

Forage Value

One of the most palatable grasses while green. Grows early in the spring and provides good forage for early grazing. This is usually con-

sidered to be the most valuable

pasture grass in North America.

Although not the most valuable grass in Arizona, it does provide large amounts of feed in irrigated pastures and in the timbered portions of the state.

Management

Kentucky bluegrass withstands long- continued, heavy grazing better than most grasses. For maxi-

mum returns under irrigation it

should be fertilized with ammonium phosphate or amonium nitrate

Figure 60. - Kentucky bluegrass (Poa pratensis) (X1/4).

at least once yearly. Where heavily grazed, two or even three applications are recommended. When moisture is adequate, low production from Kentucky bluegrass can usually be traced to low soil fertility.

Maximum returns on fertilized irrigated bluegrass pastures can be realized when two or three pastures are grazed in rotation. This makes it possible to keep stock off each pasture after irrigating while the ground is still muddy. It also permits the grasses to reach a mod-

erate height before again being

grazed.

82

EXPERIMENT STATION BULLETIN 298

A drawback to Kentucky bluemid- summer. Adequate irrigation grass is that it grows slowly for a and fertilization reduce this semi period of two to four weeks during dormant period to a minimum.

Figure 61.- Tumblegrass (Schedonnardus paniculatus) (X143).

TUMBLEGRASS

Schedonnardus paniculatus (Nutt.) Trel.

Description

Growth habit: A slender, low growing, freely branching perennial bunchgrass, 6 to 20 inches tall; tends to grow in scattered bunches.

Color: Light green, often appear-

ARIZONA RANGE GRASSES

83

ing almost silvery after the Iightcolored awns mature.

Leaves: Short and flat, often spirally twisted, about 1 /16 inch wide.

Seedheads: In this grass the fruiting portion of the plant can hardly be called a seedhead since it bears no resemblance to a head. The in-

dividual side branches on the

flower stalk are widely spaced and so slender as to be almost threadlike. On maturity the whole fruiting portion breaks off and is tumbled about by the wind.

Occurrence

Most common in northern Ari-

zona; has been reported from

Apache, Navajo, Coconino, Yavapai and Cochise counties.

This grass is generally found on open mesas and dry, open woodlands at elevations from 3500 to 7,000 feet.

Forage Value

Tumblegrass has a low palatability and produces a small volume of forage. As a consequence it ha little value as a forage producer. It is generally rated as having a little more value as feed for sheep than for cattle. However, neither kind of

stock will utilize it to any great

extent.

Management

Any management that will favor associated grasses at the expense of a nearly worthless species such as tumblegrass is good management.

Stocking at a rate that will not

harm or will increase the more pro-

ductive associated grasses on

ranges where tumblegrass is abundant should be encouraged. If these ranges are badly deteriorated they should be deferred during the summer growing season.

BURROGRASS

Scieropogon brevifolius Phil.

Description

Growth habit: A creeping sod -

grass with long, wiry, prostrate

stems from which the erect or leaning leafy flower stalks arise. The creeping stems form an open socalled "sod" that bears little resemblance to the true sod of a lawn.

The creeping stems tend to root at the joints when these come in contact with moist soil.

Color: Light green; the numerous seedheads give the plants a silvery color at maturity.

Leaves: Mostly coming from the bases of the flower stalks and from the joints of the creeping stems; short and rather hard, either flat or folded, from 1 /16 to 1/8 inch wide.

Seedheads: Very conspicuous because of their numerous, long, silvery, threadlike, somewhat twisted awns. After maturity these awns, which are usually 2 to 4 inches long, are the most noticeable thing about the plant. They do not form a compact seedhead as so many grasses do, but rather a slender, few- seeded stalk to which the awns seem to be attached.

Occurrence

Rather widespread, occurring at

5,500 feet or lower in open valleys and mesas in Apache, Navajo, Coco- nino, Mohave, Yavapai, Graham,

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EXPERIMENT STATION BULLETIN 298

Figure 62.- Burrograss

(Scleropogon brevifolius) (X%).

Cochise and Pima counties. This grass is often present on deteriorated ranges where it appears to have replaced more palatable species.

Forage Value

Burrograss has little forage value.

It has little palatability for any

class of livestock, in part because of the long wiry awns on the seeds and in part because of the harsh, stiff leaves.

Management

Most ranges where this grass is abundant have deteriorated markedly. Its presence, therefore, gen-

erally indicates that changes in

management are needed. When burrograss is widely distributed

over a range,

overall livestock numbers should be reduced or a rigid system of deferment and ro-

tation should be set up and fol-

ARIZONA RANGE GRASSES

85

Figure 63.- Plains bristlegrass (Setaria macrostachya) (X1/a).

lowed. When infestation is only tional water and salting away from local in swales or other restricted the spots of infestation, or fencing areas, the problem may be one of combined with reseeding better distribution. Development of addigrasses may provide a solution.

PLAINS BRISTLEGRASS

Setaria macrostachya H.B.K.

Description

Growth habit: A perennial

bunchgrass,

1 to 4 feet tall; the

stems often bending abruptly at the nodes.

Color: Bright green when growing, curing to orange- brown.

Leaves: Six to 16 inches long, 1/8 to % inch wide, rather thin, somewhat rough and hairy on the upper surface. As they mature, they become inrolled and curly.

Seedheads: Narrow cylindrical spikes 3 to 6 inches long that re-

86

EXPERIMENT STATION BULLETIN 298

semble ragged seedheads of timothy, but are bristly with stiff hairs extending from between the seeds.

Occurrence

Widespread and abundant in southern Arizona; reported from all counties except Apache and Mohave. This grass is most abundant on dry plains, rocky slopes, and along washes, often in partial shade of shrubs and trees, mostly at 3,500 to 5,500 feet.

Forage Value

Plains bristlegrass is a perennial bunchgrass with good to excellent forage value. The abundant, tender, basal leaves are highly palata-

ble and are readily taken by all

classes of livestock.

Management

Bristlegrass is not very resistant to grazing. It usually grows in the open shade of low trees or clumps of brush, where it is somewhat protected from grazing. Even with this

protection cattle crowd into the

bushes to eat it.

Because of its high palatability, bristlegrass is selectively grazed to

the detriment of the

grass. Although providing excellent forage, it will not tolerate heavy use. If a range is grazed lightly enough to maintain and increase this grass,

full use will not be made of the

other species. If full use is made of other species, the bristlegrass will decrease. Management, therefore, depends on the percentage of the grass cover made up of bristle

grass. Where it is relatively abundant, management should be for its maintenance. Where other perennial grasses provide most of the feed, management should be designed to maintain or improve the other species.

JOHNSON GRASS

Sorghum halepense (L.)

Pers.

Description

Growth habit: A large aggressive sod grass, 3 to 6 feet tall, growing from a scaly, underground rootstock.

Color: A rather bright green.

Leaves: Three -fourths inch wide or less; long, wavy; usually smooth

without hairs; with a thickened

white midrib.

Seedheads: Open, several branched, 5 to 20 inches long and 4 to 5 inches wide. Seeds are conspicuously black or red.

Occurrence

Throughout the state below 5,000 feet where moisture is adequate for its growth. This grass is particularly abundant along irrigation canals and along the edges of fields and roadsides. It often becomes an undesirable weed in cultivated fields.

Forage Value

Johnson grass makes good forage for all classes of livestock but is particularly valuable for cattle and horses. It is a productive hay plant.

As the plants are coarse, the best quality hay is obtained when the plants are cut in the boot stage of growth.

When growth is stopped prematurely by drought or frost, prussic acid accumulates in the stems and leaves. This forage may then be

ARIZONA RANGE GRASSES

87

Figure 64.- Johnson grass (Sorghum halepense) (X1).

highly toxic to grazing livestock.

When cut for hay, the acid re-

mains in the hay and the toxic

effects are as severe as when the standing grass is grazed.

Management

Management of Johnson grass is largely a matter of preventing poisoning. The grass is hardy, resistant to grazing, and is killed only by extreme drought.

Only a few animals should be

turned in when a Johnson grass

EXPERIMENT STATION BULLETIN 298

88 field is

first opened to

grazing.

These animals should be watched closely for the first twenty -four hours and removed at the first indication of trouble. If no poisoning is

observed during this period the

forage may be assumed to be safe.

Livestock on Johnson grass should always be closely watched, particularly during periods of sudden weather changes. The most hazardous times are in the spring and fall when frosts are likely to occur, or during summer drought.

Figure 65.- Alkali sacaton (Sporobolus airoides), plant (X1/3) and spikelet (X 10).

ALKALI SACATON

Sporobolus airoides Torr.

Description

Growth habit: A coarse, tough perennial 2 to 31/2 feet tall, growing in large, dense clumps.

Color: Pale green with a slightly grayish cast.

Leaves: Firm and fibrous; up to

18 inches long and about 1/4 inch wide.

Seedheads: Loose and open, with widely spreading branches, 12 to

18 inches long and 6 to 10 inches wide.

Occurrence

In all counties in the state ex-

- cept Mohave, Greenlee, Gila, Mari copa, and Yuma between elevations of 2,500 and 6,500 feet. It oc-

ARIZONA RANGE GRASSES

89

curs on fine -textured, often alkaline soils of bottomlands and flats, and on sandy plateaus and washes.

Forage Value

While this grass is growing vigorously it generally rates as fair to rather good forage for cattle and horses and poor to fair for sheep.

When dry, it provides poor forage for all classes of livestock. It makes fair quality hay when cut during the bloom stage.

Management

Solid stands of alkali sacaton

should be grazed during the spring and summer when growth is most active. Where it grows only as scattered plants, management should be aimed at maintaining the more abundant forage species. As this sacaton is less palatable than most of the grasses with which it grows, these grasses will be overgrazed if full use is made of the sacaton. In order to obtain proper use of the more desirable grasses, therefore, the sacaton should usually be somewhat under -used.

SAND DROPSEED

Sporobolus cryptandrus (Torr.) Gray

Description

Growth habit: Perennial bunch grass, 11/2 to 4 feet tall. The stems are erect at the base, but curve at the top. A ring of stiff, short hairs encircles the stem at the junction of the leaf blade and stalk.

Color: Bluish -green curing to a light straw yellow.

Leaves: Four to 12 inches long and 1/4 inch wide. The old leaves become frayed by the wind and

"flag" out at right angles to the

stem.

Seedheads: Seedheads a r e

branched often but entirely

enclosed by the

upper leaves. A large number of very small, hard seeds mature in late summer.

narrow, purplish,

Occurrence

Throughout the state between elevations of 200 to 7,000 feet. As its name implies, sand dropseed usually grows on sandy areas. It is not restricted to sandy sites, however, but may be encountered on a wide variety of soils.

Forage Value

Sand dropseed varies in palatability from one region to another.

In most of Arizona it is generally classed as fair to good feed for cattle and horses and fair for sheep when green. After it is mature it is poor forage for all classes of stock.

It begins growth later than most of the grasses with which it grows.

Some of the lighter soil areas in southeastern Arizona support a mixture of sand dropseed and blue grama. Although blue grama has the higher palatability, the sand dropseed is taken quite readily.

Management

Sand dropseed will increase under moderate use on ranges

where the original perennial grasses have been killed. Under heavy use it will also be killed. Because of its low palatability when dry,

90

EXPERIMENT STATION BULLETIN 298

Figure 66. -Sand dropseed (Sporobolus

(X 10).

cryptandrus), plant (X%) and spikelet this grass should be grazed during summer when it is green.

Sand dropseed has been reseeded on light, sandy soils more successfully than most grasses. The seeds are extremely small and many of them sift down into the soil where they germinate.

ARIZONA RANGE GRASSES

91

Figure 67.- Sacaton (Sporobolus wrightii), plant (X1/%) and spikelet (X 10).

SACATON

Sporobolus wrightii Munro

Description

Growth habit: A large, coarse stemmed perennial bunchgrass, 3

to 6 feet tall, growing in dense

clumps that may be up to 2 feet in diameter.

Color: Pale green with a slightly grayish cast.

Leaves: Flat or somewhat inrolled, up to 12 inches long and 3/4 inch wide.

Seedheads: Open, loosely branched with branches stiffly spreading,

1 to 2 feet long; secondary branches

closely appressed to primary

branches.

92

EXPERIMENT STATION BULLETIN 298

Occurrence

Generally on alluvial flats and bottomlands subject to flooding. On sites of this sort it has been found in Arizona at elevations of 2,000 to

6,500 feet in Graham, Pinal, Navajo, Coconino, Cochise, Santa Cruz, and Pima counties.

Forage Value

The tender early spring growth is

eaten readily by cattle and

horses. As the plants mature, the leaves and stems become coarse and tough and are eaten only sparingly. If cut before seed has set and while the plants are still growing, sacaton makes fairly good hay.

Management

Because sacaton is a coarse grass

that grows rapidly, it should be

managed carefully to make full use of the forage and to maintain saca-

ton flats in a highly productive

condition. These areas can be used most effectively by grazing them heavily in the early spring. After the grasses on the higher ranges have begun to grow, livestock should be moved from the sacaton flats and kept off until fall.

The coarse, unpalatable old growth may be removed by burning every three or four years. It is advisable to divide a flat into three or four parts and to burn one part each year. The plants will suffer

the least fire injury if they are

burned during the late winter or early spring months before growth begins.

CRINKLE -AWN

Trachypogon montufari (H.B.K.) Nees.

Description

Growth habit: A rather large,

coarse, leafy bunchgrass, commonly

11/2 to 31/2 feet tall that almost always grows intermixed with other moderately tall grama grasses.

grasses or with

Color: The actively growing

leaves have no particularly distinguishing color. After maturity, however, many of them cure to a reddish -brown or purplish color. The outside leaves are rather typically this color while the younger inside leaves are green.

Leaves: Rather wide, ranging usually from 1/8

1/4 inch, often as much as 10 to 12 inches long; flat to slightly inrolled at the edges; some-

times slightly hairy with soft,

spreading hairs.

Seedheads: Rather few, somewhat resembling a slender barley head with loose straggly awns; 3 to

6 inches long and about 1/4 inch

thick without the awns. Awns

range in length from about 11/4 to

21/4 inches and are always bent and twisted.

Occurrence

This is a typical mountain foothill grass that usually occurs on

rocky, well- drained sites inter-

mixed with shrubs and other grasses. It may be found at elevations of 1,000 to 6,000 feet and has been reported from Mohave, Graham,

Gila, Pinal, Cochise, Pima and Santa

Cruz counties.

Forage Value

In spite of its coarseness, this

ARIZONA RANGE GRASSES

93

Figure 68.- Crinkle -awn

(Trachypogon montufari) (X%).

grass ranks as fairly good forage while green. After the plants mature and the leaves dry they are grazed only lightly by cattle and even less by sheep. As it almost never forms pure stands and usually makes only a small percentage of the grass stand in any area, it rarely provides an appreciable portion of the feed on any range.

Management

Ranges where this grass is found should be managed primarily to

maintain or increase the grama

grasses with which it is usually associated. As the gramas are more palatable than crinkle -awn, this degree of use will also preserve this grass. Foothill ranges where crinkle -awn is common often become

infested with turpentine bush,

amole or other undesirable shrubs.

Where fire can be kept under control these shrubs may often be effectively removed by burning.

94

EXPERIMENT STATION BULLETIN 298

Figure 69.- Arizona cottongrass (Trichachne californica) (X1Ia).

ARIZONA COTTONGRASS (COTTONTOP)

Trichachne californica (Benth.) Chase

Description

Growth habit: A perennial

bunchgrass, 1 to 4 feet tall with

rather hard round stems.

Color: Dark bluish -green, curing to gray or straw color.

Leaves: Three to 5 inches long, flat, 18 to 1/4 inch wide. Leaves do not clasp the stem firmly, but pull away, exposing a smooth purple to green internode.

Seedheads: Several long, closely

ARIZONA RANGE GRASSES

95

appressed branches 3 to 5 inches long. Seeds drop from the branches at maturity, leaving the branches looking some w h a t like broom straw. The seed scales are covered with white silvery hairs that give the entire seedhead a cottony appearance.

Occurrence

All the counties of the state except Apache. It is most abundant in the southern part of the state, largely between elevations of 1,000 to 6,000 feet. Although one of our most common desert grasses, it seldom forms pure stands but is found interspersed with other grasses or with burroweed and mesquite.

Forage Value

Arizona cottongrass responds quickly to

spring and summer rains, makes rapid growth, and provides highly palatable green

forage.

Its palatability decreases as maturity is reached. The foliage cures well and some stems remain green in winter. These characteristics make it an important winter feed.

Management

Because cottontop is palatable throughout the year, it is frequently overgrazed. This grass comes back rapidly if it is not summer grazed. During the rest of the year it stands up well to grazing and its succulent stems provide good forage.

SLIM TRIDENS

Tridens muticus (Torr.) Nash

Description

Growth habit: A small, perennial bunchgrass, 12 to 15 inches high, narrow in outline.

Color: Light bluish -green, curing to a light straw yellow.

Leaves: Three to 5 inches long, about 1/8 inch wide, rolled in at the edges.

Seedheads: Seeds are borne in narrow, cocoon -like clusters on long, thin stalks, leafy for almost their entire length. When immature, the outer scales of these clust-

ers are purple with white upper

edges. These scales overlap very closely,

giving the seedheads a

scaly appearance. When mature, the seeds drop off, leaving a pair of paperlike scales throughout the year.

that persist

Management

As slim tridens usually makes up a minor portion of the forage on a range, management should be based largely on requirements of the more valuable species. This grass and those associated with it grow and should be grazed primarily from July through September.

Occurrence

All counties except Apache, Graham, Greenlee, Navajo, and Mari

copa up to an elevation of about

5,500 feet. It grows commonly on rocky hillsides intermixed with shrubs and other grasses.

Forage Value

Fair to good forage for all classes of livestock. The plants are scattered and seldom make up a large per-

96

EXPERIMENT STATION BULLETIN 298

centage of the total forage pro-

duced on a range.

FLUFFGRASS

Tridens pulchellus (H.B.K.) Hitchc.

Description

Growth habit: A low, densely tufted perennial bunchgrass 3 to 6 inches tall, often with runners and sometimes forming an open sod.

Color: Fuzzy bluish -green, curing to a grayish- white.

Leaves: Thin and wiry, 1 to 2 inches long, growing in distinct groups at the base of the stem and at the end of the flowerstalks just beneath the seedheads.

Seedheads: Borne on stems that are leafless from the base of the plant to just below the seeds. The

seeds form among a bunch of

leaves at the end of the stem. The flower parts are densely silvery hairy. Seeds usually fall at maturity, leaving a pair of distinct papery bracts.

Figure 70. -Slim tridens (Tridens muticus (X1/4).

Occurrence

Throughout the state up to an

elevation of about 5,500 feet.

It rarely grows in abundance on productive sites and is a reliable indicator of areas of low potential productivity. Reseeding is not recommended on areas that support an abundance of fluffgrass.

Forage Value

Fluffgrass is one of the poorest forage grasses on Arizona ranges.

When young and actively growing the plants are covered with a bluish -white down that may be objectionable to livestock. Later, when the plants mature, the leaves become harsh, wiry and sharp pointed. Because of these features fluff

grass is normally grazed only on ranges where there is a feed shortage.

Management

Even moderate use of this low

-

value plant is evidence that too

little forage is being produced to carry the number of animals that are on the range. In this case a re-

duction in numbers is

required, both from the point of view of the

immediate welfare of the cattle

and the long -time condition of the range.

ARIZONA RANGE GRASSES

97

Figure 71.- Fluffgrass (Tridens pulchellus) MIA).

98

SPIKE TRISETUM

Trisetum spicatum (L.) Richt.

Description

Growth habit: A perennial bunch grass that usually grows in rather small dense tufts.

Color: Slightly lighter green than average but not enough so to distinguish this grass markedly from others with which it grows.

Leaves: Two to 6 inches long, % to 1/4 inch wide, rather flat or folded or the edges inrolled on drying; appearing hairless or sometimes with very fine, somewhat sparse hairs.

Seedheads: Spikelike, rather

dense, about 1 to 4 inches long and

1/4 to 1 inch broad, greenish purple in color with awns that give the heads a fuzzy appearance.

Occurrence

Spike trisetum is a high -altitude grass that occurs from 10,000 to

12,000 feet elevation on Mt. Baldy in Apache county and in the San

Francisco mountains of Coconino county. It is most common in open meadows or boulder -strewn areas near or above timberline. It rarely occurs in pure stands but is often an important constituent of high mountain summer ranges.

EXPERIMENT STATION BULLETIN 298

Figure 72. -Spike trisetum (Trisetum spicatum) (X%).

ARIZONA RANGE GRASSES 99

Forage Value

This grass is rated as moderately good to good forage for cattle and horses and fair to good for sheep.

It begins growth early after the

snows have melted and remains green throughout the summer. The seedheads seem to reduce its palatability somewhat with the result that it is grazed most readily early in the season before the seeds have

set or later in the summer after

they have matured and dropped.

Management

Because of the short grazing sea-

son at the high altitudes where

trisetum occurs, management is difficult. Care should be taken, however, to see that grazing is not so heavy as to break down the grass sod and expose the soil to washing from the relatively heavy precipitation typical of these high -altitude areas.

100 EXPERIMENT STATION BULLETIN

298

BIBLIOGRAPHY

Additional information on many of the grasses discussed in this bulletin may be obtained by referring to these publications

Allred, B. W. Practical grassland management. Sheep and Goat Raiser Magazine,

1950.

Archer, S. G. and Bunch, C. E. The American grass book. Univ. Okla. Press,

Norman, Okla. 1953.

Billings, W. D. Grasses and clovers for Nevada farm and range. Nev. Agr. Ext.

Serv. Bul. 89. February, 1941.

Catlin, C. N. Composition of Arizona forages, with comparative data. Ariz. Agr.

Exp. Sta. Bul. 113. December, 1925.

Cook, C. W., and Harris, L. E. The nutritive content of the grazing sheep's diet on summer and winter ranges of Utah. Utah Agr. Exp. Sta. Bul. 342.

November, 1950.

Cook, C. W., and Harris, L. E. The nutritive value of range forage as affected by vegetation type, site, and stage of maturity. Utah Agr. Exp. Sta. Tech.

Bul. 344. December, 1950.

Crider, F. I. Three introduced lovegrasses for soil conservation. U. S. Dept. Agr.

Circular No. 730. 1945.

Departments of Animal Husbandry and Agricultural Chemistry. Preliminary report on the composition of range forage plants as related to animal nutrition. Idaho Agr. Exp. Sta. Mimeo. Leaflet 13. May, 1937.

Fraps, G. S., and Fudge, J. F. The chemical composition of forage grasses of the east Texas timber country. Texas Agr. Exp. Sta. Bul. 582. March, 1940.

Fudge, J. F., and Fraps, G. S. The chemical composition of grasses of northwest

Texas as related to soils and to requirements for range cattle. Texas

Agr. Exp. Sta. Bul. 669. May, 1945.

Gordon, A., and Sampson, A. W. Composition of common California foothill plants as a factor in range management. Calif. Agr. Exp. Sta. Bul. 627.

March, 1939.

Gould, F. W. Grasses of southwestern United States. Univ. of Ariz. Biol. Sci. Bul.

No. 7. January, 1951.

Griffiths, D. Native pasture grasses of the United States. U. S. Dept. Agr. Bul. 201.

1915.

Harlan, Jack R., Denman, C. E. and Elder, W. C. Weeping lovegrass. Okla. Agr.

Exp. Sta. Forage Crops Leaflet No. 16. 1953.

Hitchcock, A. S. and Westgate, J. M. Forage plants for Kansas. Kans. Agr. Exp.

Sta. Bul. 102. March, 1901.

Hopper, T. H., and Nesbitt, L. L. The chemical composition of some North Dakota pasture and hay grasses. N. Dak. Agr. Exp. Sta. Bul. 236. June, 1930.

Humphrey, R. R. Arizona range resources, II. Yavapai County. Ariz. Agr. Exp. Sta.

Bul. 229. July, 1950.

Humphrey, R.R. Forage production on Arizona ranges, III. Mohave County. Ariz.

Agr. Exp. Sta. Bul. 244. February, 1953.

Humphrey, R. R. Forage production on Arizona ranges, IV. Coconino, Navajo and

Apache Counties. Ariz. Agr. Exp. Sta. Bul. 266. October, 1955.

Kearney, T. H., and Peebles, R. H. Arizona flora. Univ. of Calif. Press.

1951.

McCall, R., Clark, R. T., and Patton, A. R. The apparent digestibility and nutritive value of several native and introduced grasses. Mont. Agr. Exp. Sta.

Tech. Bul. 418. October, 1943.

Meredith, D. (Editor). The grasses and pastures of South Africa. Central News

Agency, Union of S. Africa. 1955.

Morris, H. E., Booth, W. E., Payne, G. F. and Stitt, R. E. Important grasses on Mon

tana ranges. Mont. Agr. Exp. Sta. Bul. 470. 1950.

Office of Grazing Studies, U. S. Forest Service. National forest range plants grasses. Pt. I. U. S. Dept. Agr. 1914.

Piper, C. V. Bermuda grass (Cynodon dactylon). U. S. Dept. Agr. Bur. Plant Ind.

F. C. I. 33. April, 1916.

Piper, C. V. Important cultivated grasses. U. S. Dept. Agr. Farmer's Bul. 1254, Rev.

October, 1931.

Reid, E. H. Important plants on national forest ranges of eastern Oregon and eastern Washington. U. S. Dept. Agr. Range Res. Rept. No. 1. May, 1942.

Reitz, L. P., and Morris, H. E. Important grasses and other common plants on Montana ranges. Mont. Agr. Exp. Sta. Bul. 375. November, 1939.

Sampson, A. W. Important range plants: their life history and forage value. U. S.

Dept. Agr. Bul. 545. 1917.

Sampson, A. W., and Chase, A. Range grasses of California. Calif. Agr. Exp. Sta.

Bul. 430. 1927.

Sampson, A. W., Chase, A. and Hedrick, D. W. California grasslands and range forage grasses. Calif. Agr. Exp. Sta. Bul. 724. May, 1951.

Sarvis, J. T. Grazing investigations on the Northern great plains. N. Dak. Agr.

Exp. Sta. Bul. 308. December, 1941.

Stanley, E. B., and Hodgson, C. W. Seasonal changes in the chemical composition of some Arizona range grasses. Ariz. Agr. Exp. Sta. Tech. Bul. 73.

June, 1938.

Stoddart, L. A., and Greaves, J. E. The composition of summer range plants in

Utah. Utah Agr. Exp. Sta. Bul. 305. December, 1942.

Thompson, J. B. Some Florida grasses. Univ. of Fla. Div. of Agr. Ext. and U. S.

Dept. Agr. Bul. 28. April, 1921.

Thornber, J. J. The grazing ranges of Arizona. Ariz. Agr. Exp. Sta. Bul. 65, 1910.

U. S. Department of Agriculture, Forest Service. Range plant handbook. U. S.

Govt. Printing Office. 1937.

U. S. Department of Agriculture. Grass, yearbook of agriculture. 1948.

Watkins, W. E. Composition of range grasses and browse at varying stages of maturity. N. Mex. Agr. Exp. Sta. Tech. Bul. 311. December, 1943.

Westover, H. L. Crested wheatgrass. U. S. Dept. Agr. Leaflet No. 104. 1934.

Wheeler, W. A. Forage and pasture crops. D. Van Nostrand Company, Inc., New

York. 1950.

Whitfield, C. J., Jones, J. H., Fudge, J. F., and Jones, J. M. Protein and mineral content of forages at the Amarillo Conservation Exp. Sta. Texas

Agr. Exp. Sta., Prog. Rep. 1061. February, 1947.

COMMON NAME INDEX

Common Name

Scientific Name

ALKALI SACATON Sporobolus airoides Torr

ARIZONA COTTONGRASS Trichachne californica (Benth.) Chase

ARIZONA FESCUE Festuca arizonica Vasey

BERMUDA GRASS Cynodon dactylon (L.) Pers

BIG GALLETA Hilaria rigida (Thurb.) Benth

BLACK GRAMA Bouteloua eriopoda Torr

BLUE GRAMA Bouteloua gracilis (H.B.K.) Lag

BLUE PANIC Panicum antidotale Retz

BLUESTEM (See western wheatgrass)

BOER LOVEGRASS Eragrostis chloromelas Steud

BULLGRASS Muhlenbergia emersleyi Vasey

BURROGRASS Scleropogon brevifolius Phil

BUSH MUHLY Muhlenbergia porteci Scribn

CANE BEARDGRASS Andropogon barbinodis Lag

CHEATGRASS Bromus tectorum L

COTTON TOP (See Arizona cottongrass)

CRESTED WHEATGRASS Agropyron desertorum (Fisch.) Schult

CRINKLE -AWN Trachypogon montufari (H.B.K.) Nees

CURLY MESQUITE Hilaria belangeri (Steud.) Nash

DEERGRASS Muhlenbergia rigens (Benth.) Hitchc

DESERT SALTGRASS Distichlis stricta (Torr.) Rydb

FEATHER FINGERGRASS Chloris virgata Swartz

FLUFFGRASS Tridens pulchellus (H.B.K.) Hitchc

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Common Name

Scientific Name

FOXTAIL BROME (See red brome)

FOXTAIL CHESS (See red brome)

FRINGED BROMEGRASS Bromus ciliatus L

GALLETA Hilaria jamesii (Torr.) Benth

GREEN SPANGLETOP Leptochloa dubia (H.B.K.) Nees

HAIRY GRAMA Bouteloua hirsuta Lag

HALL'S PANIC GRASS Panicum halliiVasey

HOE GRASS (See bush muhly)

INDIAN RICEGRASS Oryzopsis hymenoides (Roem. & Schult.) Ricker

JOHNSON GRASS Sorghum halepense (L.) Pers.

JUNEGRASS Koeleria cristata (L.) Pers

KENTUCKY BLUEGRASS Poa pratensis L

LEHMANN LOVEGRASS Eragrostis lehmanniana Nees

LITTLE BLUESTEM Andropogon scoparius Michx.

MOUNTAIN MUHLY Muhlenbergia montana (Nutt.) Hitchc

MUTTONGRASS Pod fendleriana (Steud.) Vasey

ORCHARDGRASS Dactylis glomerata L

PAPPUSGRASS Pappophorum mucronulatum Nees

PINE DROPSEED Blepharoneuron tricholepis (Torr.) Nash

PLAINS BRISTLEGRASS Setaria macrostachya H.B.K

PLAINS LOVEGRASS Eragrostis intermedia Hitchc

POVERTY THREEAWN Aristida divaricata Humb. and Bonpl

PURPLE THREEAWN Aristida purpurea Nutt

RED BROME Bromus rubens L

RED THREEAWN Aristida longiseta Steud.

RINGGRASS Muhlenbergia torreyi (Kunth.) Hitchc

RING MUHLY (See ringgrass)

ROTHROCK GRAMA Bouteloua rothrockii Vasey

SACATON Sporobolus wrightii Munro

SAND DROPSEED Sporobolus cryptandrus (Torr.) Gray

SANTA RITA THREEAWN Aristida glabrata (Vasey) Hitchc

SHEEP FESCUE Festuca ovina L

SIDEOATS GRAMA Bouteloua curtipendula (Michx.) Torr.

SIXWEEKS GRAMA Bouteloua barbata Lag

SIXWEEKS NEEDLE GRAMA Bouteloua aristidoides (H.B.K.) Griseb

SIXWEEKS THREEAWN Aristida adscensionis L

SLENDER GRAMA Bouteloua filiformis (Fourn.) Griffiths

SLENDER WHEATGRASS Agropyron trachycaulum (Link) Malte

SLIM TRIDENS Tridens muticus (Torr.) Nash

SPIKE MUHLY Muhlenbergia wrightii Vasey

SPIKE PAPPUSGRASS Enneapogon desvauxii Beauv

SPIKE TRISETUM Trisetum spicatum (L.) Richt

SPRUCETOP GRAMA Bouteloua chondrosioides (H.B.K.) Benth

STINKGRASS Eragrostis megastachya (Koel.) Link

TANGLEHEAD Heteropogon contortus (L.) Beauv

TEXAS BEARDGRASS Andropogon cirratus Hack

TEXAS BLUESTEM (See Texas beardgrass)

TEXAS TIMOTHY (See woiftail)

TOBOSA Hilaria mutica (Buckl.) Benth

TUMBLEGRASS Schedonnardus paniculatus (Nutt.) Trel

VINE MESQUITE Panicum obtusum H.B.K

WEEPING LOVEGRASS Eragrostis curvula (Schrad.) Nees

WESTERN WHEATGRASS Agropyron smithii Rydb.

WILMAN LOVEGRASS Eragrostis superba Peyr

WOLFTAIL Lvcurus phleoides H.B.K

WOOLLY BUNCHGRASS Elyonurus barbiculmis Hack.

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ORGANIZATION

Board of Regents of the University and State Colleges of Arizona

Ernest W. McFarland (ex officio),

A.B., M.A., J.D., LL.D

Marion L. Brooks (ex officio),

B.S., M.A

Governor of Arizona

State Supt. of Public Instruction

John M. Jacobs

Evelyn Jones Kirmse, A.B., A.M., President

Alexander G. Jacome, B.S., Treasurer

William R. Mathews, A.B., LL.D., Secretary

Lynn M. Laney, B.S., J.D

Samuel H. Morris, A.B., J.D., LL.D

John G. Babbitt, B.S

Elwood W. Bradford, B.S

Term expires Jan., 1959

Term expires Jan., 1959

Term expires Jan., 1961

Term expires Jan., 1961

Term expires Jan., 1963

Term expires Jan., 1963

Term expires Jan., 1965

Term expires Jan., 1965

Richard A. Harvill, Ph.D

Robert L. Nugent, Ph.D

David L. Patrick, Ph.D

Norman S. Hull, LL.B

President of the University

Vice - President of the University

Vice -President of the University

Vice -President of the University

EXPERIMENT STATION ADMINISTRATION

Harold E. Myers, Ph.D

Richard K. Frevert, Ph.D

John Burnham, B.A

Dean

Director

Editor

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Inld and di,jtl;rtrtl

Iluerr.

1}t:tri

Ciille;f trf . t`it'rll!tii'c ui\ of

\ríitaui

141..._,,.d

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