Common Arizona Range Grasses

Item Type text; Book

Authors Humphrey, Robert R.; Brown, Albert L.; Everson, A. C.

Publisher College of Agriculture, University of Arizona (Tucson, AZ)

Download date 03/10/2021 00:41:11

Link to Item http://hdl.handle.net/10150/213119 COMMON ARIZONA RANGE GRASSES THEIR DESCRIPTION; FORAGE VALUE AND MANAGEMENT

Agricultural Experiment Station University of Arizona, Tucson FOREWORD The kind of plants that grow on a range affects 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 pro- ducts 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. It makes up more than 80 per cent of the diet of cattle and more than 60 per cent of the diet of sheep. 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. 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 fifty -three range grasses important to the state of Arizona and gives their identifying characteristics, sea- sonal forage values, and the management practices that will maintain each grass in a productive condition. The drawings in this bulletin were executed by Mrs. Lucretia Breazeale Hamilton. Their fine quality adds great- ly to the value of the publication. Although the information included was obtained from many sources in addition to the authors' experience, Grasses of Southwestern United States, by Frank W. Gould was a particularly valuable source of material on descriptions and ranges.

This bulletin was first printed in November, 1952. Except for change of cover picture, correction of minor typogra- phical errors, addition of two references, and rearrangement of type, this reprint is identical to the first printing. COMMON ARIZONA RANGE GRASSES Their Description, Forage Value, and Management

BY ROBERT R. HUMPHREY, ALBERT L. BROWN AND A. C. EVERSON GRASSES AND GRAZING A knowledge of the functionssumed, however, the raw materials of the roots, stems, and leaves ofto build new leaves must come grass plants is of value to contin-from these reserves, and they dim- ued, profitable range management.inish more rapidly. The faster the Since grasses are living organisms,rate of growth, the greater the they are affected by all environ-drain on the food reserves. mental factors such as temperature, Food reserves are drawn on and moisture, light, soil, air, and otherdiminish as spring growth starts. plants and animals. These factorsThis is repeated with most of our determine where and when a plantgrasses as growth is resumed after will grow, and how well it willthe start of the summer rains. As survive. seeds are formed and begin to A healthy perennial grass, grownripen, food reserves are used heav- under natural, normal conditions,ily and are usually at their lowest follows a fairly definite seasonalebb. As the seeds become ripe, growth cycle.Itbegins growthplant growth slows down and food when moisture and temperaturenot required for seed production is conditions are favorable, producesagain stored in the roots, stems, seed stalks, and the seed maturesand leaves. and is disseminated. Finally the Because of this food- storage -and- grass stops growing and becomesdepletion cycle, grasses are affected dormant until favorable conditionsdifferently when grazed at differ- again prevail. These visible physi-ent times of the year. Grazing dur- cal changes of the plant are accom-ing the dormant season has little panied by changes in its internaleffect on the physiology of the chemistry. plant. Growth is essentially at a As grasses mature, sugars andstandstill and the bulk of the food starches are stored in the roots,reserves that will be used when seeds, stems, and leaves. In mostgrowth is resumed are stored in range grasses the reserves storedthe roots. in the roots maintain life in the On the other hand, excessive plant through the dormant monthsgrazing during the dormant season and enable it to resume growth inmay affect the grasses indirectly. If the spring. These reserves diminishgrazing is too heavy, all litter may very gradually during the dormantbe removed, the soil may erode and period because growth is almost atmuch of the water that should go a standstill. When growth is re-into the soil may be lost as runoff.

1 2 EXPERIMENT STATION BULLETIN 243 (REPRINT) When plants are grazed heavilymaturity. Digestibility decreases as early in the growing season, mostprotein declines and as crude fiber of the young leaves that manufac-increases. Phosphorus c o n t e n t ture food may be destroyed. Newclosely parallels protein content, growth must then come from re-being highest in the early growth serve food stored in the roots. Re-stages, and decreasing later. peated removal of the young leaves One of the principal goals of causes the root reserves to be de-range management is to develop a pleted and the plant will die orsystem of grazing that will utilize become so weak that it is easilythe plants during the period of killed by drought or other adversemaximum nutritive value (when conditions. the plants are growing) without Any grazing during the growthinjuring the plant. period weakens a grass to some ex- Fortunately,mostrangesin tent because it removes the leavesgood condition support a variety of which manufacture food and thusforage plants. Although all grasses reduces the source of food reserves.follow similar trends in food re- Damage is greatest, however, whileserve, the different species vary in theplantismaking maximumthe time of these trends. Some growth and when the reserves arebegin growth early in the spring, lowest, just before and during seedwhile others do not grow until sum- production. Moderate grazing whenmer. Furthermore, different grasses growth is beginning, or after thehave different curing qualities, a seeds are fully ripe, has a muchfact that influences their use dur- smaller effect on the well -being ofing dormant periods. Short grasses the plant. in general cure well, maintain a Reserves built up during onehigh proportion of their protein year's growing season affect thecontent throughout the year, and vigor, seed production and yieldhave a small amount of crude fiber. of the grass the following year. Tall grasses tend to lose their Occasional season -long grazing de-protein more rapidly and show a ferment allows the reservestocorrespondingly rapid increase in buildup,resultinginstrongercrude fiber. However, tall grasses plants the following year. Defer-produce more forage than short ment also permits maximum seedgrasses and can be most advantag- production and allows seedlings toeously used when their nutritive become established before beingvalue is highest. grazed. Each range unit presents indi- The feeding value of the grassesvidual problems. The rancher, how- follows a pattern closely related toever, can become acquainted with the stage of growth. Protein con-the different grasses on his ranch, tent is highest during the earlytheir growth cycles, and their feed- growth stages and decreases as theing value. He can devise a manage- plant matures. Crude fiber contentment plan that will maintain or is lowest during the early stages,improve his range while maintain- butincreaseswith approachinging a high level of animal nutrition. COMMON ARIZONA RANGE GRASSES 3

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node- r _;; A -- }a` rhizome,j.- tlarous roots^ 8 Figure 1.- Structure of plant. A, general habit of grass; B, rhizomes; C, stolon; D, rhizome and stolon intergradation (X1/2).

In the pages to follow, it will beNode necessary to use a few more or less The place on a stem where the technical terms in describing someleaf is attached, usually somewhat of the grasses. These terms are: swollen. internode Awn The portion of the stem between A slender, hairlike bristle bornetwo successive nodes. on the scales that surround theSpike seed. Awns may range from 1/4 inch An unbranched, elongated flower - or less to 8 or 10 inches. head or seedhead. 4 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 2.- Crested wheatgrass (Agropyron desertorum) (X1/2).

CRESTED WHEATGRASS Agropyron desertorum (Fisch.) Schult.

Description Leaves: Flat, 6 to 10 inches long. Growth habit: Long -lived, mod- Seedheads: 11 /2 to 21/2 inch -long eratelycoarse perennial bunch-spikes, borne singly on the ends of grass, 2 to 3 feet tall. the stalks. The name refers to the Color: Bright green, curing toflat seedhead that somewhat re- straw color. sembles a head of wheat. COMMON ARIZONA RANGE GRASSES 5 Occurrence Management Primarily in the northern part of the state or at elevations above Crested wheatgrass is used more 5,000 feet. This grass is not nativewidely for reseeding than any other to Arizona, and generally occursgrass. It has been used successfully where it has been planted on run-in the sagebrush, shortgrass, pin- down ranges or abandoned crop-yon- juniper, and ponderosa pine land. vegetation types. Forage Value Reseeded stands generally be- Crested wheatgrass produces acome established during the sum- large volume of high quality for-mer. They should not be grazed age. It begins to grow early in theduring the year of seeding, nor dur- spring, becomes dry before theing spring or summer of the follow- summer rains and resumes growthing year. Well- established stands after the summer rains have begun.can be lightly grazed during fall of The plants remain partly greenthe second year without harm to through the fall months unless thethe grasses. season is abnormally dry. When Crested wheatgrass withstands fall rains come early the plantsheavy grazing better than most again begin to grow and providegrasses. When closely grazed, how- feed until covered by snow. Thus,ever, livestock should be excluded crested wheatgrass furnishes greenabout every third year from the forage in early spring and late falltime summer growth begins until when other succulent feed is scarce.the seed crop has matured. It is highly palatable to all classes of livestock. Crested wheatgrass can be graz- Because crested wheatgrassised to best advantage while green rather coarse, it makes poor forageand actively growing. However, if when dry. When green and active-cattle are fed a high -protein sup- ly growing, on the other hand,plement while grazing dry wheat - there are few grasses that are moregrass, they will make good use of nutritious. the grass.

WESTERN WHEATGRASS (BLUESTEM) Agropyron smithii Rydb. Description wise on the upper surface, firm, Growth habit:A moderatelytapering to a slender point. coarse perennial sodgrass l to 21/2 Seedheads:Dense, narrow, un- feet tall, spreading by undergroundbranched spikes 2 to 6 inches long. rootstocks. Occurrence Color: Blue -green when grow- On dry hills, moist open ground, ing, curing to a washed -out strawand open pine forests in Apache, color. Navajo, Coconino, Yavapai, Gra- Leaves: Four to 12 inches long,ham, and Pima counties from 3,000 3/16 to 1 inch wide, ridged length-to 7,000 feet. The grass is adapted 6 EXPERIMENT STATION BULLETIN 243 (REPRINT) 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 westernwheatgrassis green it is highly palatable for all classesoflivestock. 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 toearly -dough stage w e s t ern wheatgrass makes very good hay. The stems are rather coarse but the Figure 3.- Western wheatgrass (Agro- protein content is high and cattlepyron smithii), plant (X1/4) and spike - and horses eat the hay readily. let (X 10) . Management Care should be taken not to grazelightly during the spring months bluestem wheatgrass too closely.than is usually the case on most of Heavy grazing reduces the forageour rangelands. Overgrazing dur- yield and may result in death ofing the spring can be offset by re- some of the plants. In order toseeding adjacent run -down areas maintain or increase the stand ofwith bluestem wheatgrass or crest- this grass, it should be grazed moreed wheatgrass. CANE BEARDGRASS* Andropogon bardinodis Lag. Description colored midrib. Growth habit: Coarse perennial bunchgrass 2 to 4 feet tall. Seedheads: Seeds are borne in Color: Bluish green, curing totufts of silvery hair on the end of dull red or yellow. the long seed stalks. These seed - Leaves: Wide, fairly long, occur-heads are usually 2 to 4 inches long ring basally and on the flowerand about twice as long as wide. stalks. When dry they cure to a Other: A ring of stiff hairs occurs reddish -brown color with a light-at the nodes. * Silver beardgrass (Andropogon saccharoides) is essentially identical with cane beardgrass. All of the information given above applies also to silver beard - grass. COMMON ARIZONA RANGE GRASSES 7

Figure 4. -Cane beardgrass (Andropogonbardinodis), plant(X1 /3)and spikelet (X 10). Occurrence Forage Value At elevations of 1,000 to 5,800 feet Because the grass is coarse and in all counties in the state exceptthe nutrients tend to leach out Apache and Mohave. It is particul-afterthe plantsaredry,cane arly abundant along graded road-beardgrass is generally rated as sides and banks of washes or otheronly fair forage. During the sum- places where the soil has been ex-mer when the plants are actively posed. It is also common on dry,growing they are grazed readily, rocky or sandy slopes. On openparticularly by cattle and horses. rangeland it occurs principally inAt that time they make good feed areas of water concentration. unless there is an abundance of 8 EXPERIMENT STATION BULLETIN 243 (REPRINT) more palatable, finer -leaved spe-during the fall and winter but the cies. forage is of a poorer quality at that Management time. When grazed during the Cane beardgrassis most pro-summer, at least a third of the seed ductive when grazed during thestalks should remain ungrazed for summer when the plants are act-seed production and to permit the ively growing. It may be grazedplants to build a strong root system.

TEXAS BEARDGRASS (TEXAS BLUESTEM) Andropogoncirratus Hack. Description Forage Value Growth habit: Perennial bunch - Although Texas beardgrassis grass 11 /2 to 2 feet tall. fine -leaved, it has hard, wiry stems. Color: Bluish- green, curing to aThis may account for its rather low reddish or purplish brown. palatability. It usually rates as only Leaves: Slender, straight; fromfair forage, probably because it 1/16 to1/4 inches wide, many ofgenerallygrowsamonghighly them attached on the upright stems,palatable grama grasses. as well as the base of the plant. Management Seedheads: Slender, cylindrical, Texas beardgrass is most pala- spikelike, 1 to 21/2 inches long, nottable during the summer months hairy. from July into September when it is growing most actively. It should Occurrence be grazed for the most part at this time. During the fall, winter and Reported from Coconino, Yaya-spring the plants are dry and are pai, Graham, Gila, Pinal, Cochise,eaten sparingly unless there is a Pima, and Santa Cruz counties. Itshortage of other feed. When graz- usuallygrowsonsteep,rockyed during the growing season a slopes at elevations of from 2,000third of the seed stalks should be to 7,500 feet and is frequently asso-left for seed production and to ciated with oaks or pinyon andassist in building up a vigorous root juniper. system.

LITTLE BLUESTEM Andropogon scoparius Michx. Description dark reddish -brown. Growth habit: A perennial bunchgrass 2 to 5 feet tall with sod - Leaves: Usually flat, rather stiff, forming tendencies. The plants are1/16 to 3/16 inches wide, usually 3 erect and rather slender, with theto 5 but sometimes as much as 10 stems and leaves rather closelyinches long. bunched. Seedheads:Slender,spikelike Color: Bluish -green, curing to aand not conspicuously hairy. COMMON ARIZONA RANGE GRASSES 9

Figure 5. -Texas beardgrass(Andropogon cirratus) (X1/3) . Occurrence ther low. Protein content has been Reported from Apache, Navajo,found to be about half that of blue Coconino, Yavapai, Cochise, Pima,grama at the same stage of growth. and Santa Cruz counties. It com- When cut early this grass makes monly grows in oak or juniperhay of fair quality. It should be cut woodlands, and in open pine for-no later than the late bloom stage. ests or mountain meadows at ele-Otherwise the nutritive value and vations above 4,000 feet. palatability of the hay will be low. Management Forage Value Little bluestem is most produc- This grass does not rate verytivewhengrazedduringthe high as forage. It is not very pala-months of July to September while table and its nutrient value is ra-the plants are growing. It may be 10 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 6.- Little bluestem(Andropogon scoparius) (X1). grazed during the fall and wintersummer, at least one third of the but makes comparatively poor feedseed stalks should be left for seed and is not readily taken when dor-production and to permit the plants mant. When grazed during theto build a stronger root system. COMMON ARIZONA RANGE GRASSES 11

Figure 7.- Sixweeks threeawn (Aristida adscensionis) (X1/2). 12 EXPERIMENT STATION BULLETIN 243 (REPRINT) SIXWEEKS THREEAWN Aristida adscensionis L. Description turbed by heavy grazing or culti- Growth habit: A fine -leaved an-vation. nual grass extremely variable in size. Plants may be 3 to 30 inchesForage Value tall,sizedepending largelyon Sixweeks threeawn is one of our availablemoisture. The severalbetter annual grasses, but provides stems are attached at the base' ofpoorer forage than most perennials. the plant and are usually wideAlthough it will grow and set seed spreading. at any time of the year when mois- Color: Yellow to bright green,ture and temperature are favor- curing to a straw color. Seedheadsable, sixweeks threeawn is most may be purple. prevalent during the summer and Leaves: Mostly short, 1/16 to 2/16is commonly classed as a summer incheswide,the edges usuallyannual. rolled inward when dry. Management Seedheads: Long and narrow, Sixweeks threeawn may produce c o n s i s t i n gof many slenderan abundance of feed for a short branches, lying close to, and rather period of time. Its principal.disad- erect against the central stem. Eachvantages are that it produces green branch bears a slender seed closelyfeed only for a short period, and enclosed by its surrounding scales.that the nutrients leach out quick- Three 1/2-inch -long awns divergely. The plants apparently lose most from the top of these scales. of their nutritive value soon after Occurrence they dry. Widespread in the state below Because of the short growing 6,000 feet. This grass is most abund-period, ranges with an abundance ant at elevations of about 4,000 feet,of sixweeks threeawn or other pala- and is not common in the driertable annuals often can be grazed portions of the state where creo-to better advantage by steers rather sote bush or salt -tolerant shrubsthan a breeding herd. Enough of predominate. Sixweeks threeawnthe plants should be left in all cases makes its best growth on naturalto provide litter for soil and mois- grassland sites that have been dis-ture conservation.

POVERTY THREEAWN* Aristida divaricata Humb. and Bonpl. Description Leaves: Mostly 1/16 inch wide, Growth habit: Perennial bunch -about 6 inches long, inrolled and grass 1 to 3 feet tall. spirally twisted on drying. Color:Dark green, curing to Seedheads: Very open, spreading straw -color. branches extending at right angles * For footnote, see next page. COMMON ARIZONA RANGE GRASSES 13 from the central axis. Each seed bearsthreespreading,hairlike awns at its tip. Occurrence The distributions of these three grasses overlap to cover most of thestate 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 isgenerally 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. Itis grazed rather lightly after other, more palatable grasses begin to grow. Management Ranges with an abundance of povertythreeawn may provide more spring grazing than ranges where this grass is not abundant.Figure 8.- Poverty threeawn (Aristida Where this grass occurs sparsely,divaricata)(X1/4) . proper use should be based on the amount of grazing that more pro-to be maintained, at least one third ductiveassociatedgrasseswillof the seed stalks should remain stand. Where poverty threeawn isungrazed.

SANTA RITA THREEAWN Aristida gladrata(Vasey) Hitchc. Description stalks from about 1/2 to 11/4 inches Growth habit: Small perenniallong; narrow, inrolled, not hairy. bunchgrass with hard, round, wiry Seedheads: Slender, several lying stems 1 to 11/2 feet tall. close to and rather erect against Color: Green to gray -green al-the central stem. Each seed bears most year long. at its tip three slender spreading Leaves: Short, those on the seed-awns each about 3/4 inch long. The * 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. 14 EXPERIMENT STATION BULLETIN 243 (REPRINT) column connecting the awns to the seed scales breaks off at slight pres- sure 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. Forage Value Although the stems are hard and wiry and the plant is not very leafy it is grazed readily, particul- arly late in the season after most of the other grasses are dry. Management Santa Rita threeawn withstandsFigure 9. -Santa Rita threeawn (Aris- rather heavy, long -continued graz-tida glabrata) , plant (X1/4) and spike - ing better than most of the gramalet (X 10). grasses that commonly grow withgreen feed. The plants should not it. Ranges with an abundance ofbe grazed too closely. About one this grass should be grazed duringfourth of the seed stalks should be the spring and fall drought periodsleft at the end of the grazing sea- to take advantage of the seasonalson. RED THREEAWN Aristida longiseta Steud. Description out at right angles from the tip of Growth habit: Perennial bunch -the seed. The awns are red when grass, 6 to 15 inches tall, growingimmature. in thick clumps. Color: Green, curing to a tan.Occurrence Old leaves from the year before Rather widespread and locally usually give the growing plant aabundant in all counties except grayish green color. Maricopa, Yuma, and Santa Cruz, Leaves: Short, rather stiff andbetween elevations of 3,000 and inrolled. 6,000 feet. It is most common on Seedheads: Seed stalks are usual-sandy or gravelly plains and hills ly short and branched. The scalesbut becomes established on better surrounding each seed bear threeareas when the more palatable awns, 2 to 3 inches long, spreadinggrasses are grazed out. COMMON ARIZONA RANGE GRASSES 15

Figure 10. -Red threeawn (Aristida longiseta), plant (X1 /3) and seed (X 1). Forage Value Management Red threeawn has a low palata- Red threeawn is much less pala- bility rating. Because of its abun-table than blue grama or the other dance in some areas, however, itgrasses with which it is commonly furnishes rather large amounts ofassociated. As a consequence, it in- forage, particularly from late Julycreases on heavily grazed ranges to early September. Growth beginsat the expense of the better forage late in the spring but little feed isplants. Although a valuable indi- produced until the summer rainscator of range deterioration, red begin. During the fall and winterthreeawn may indicate only that when the plants are dry it has verythe siteis arid and has a well - little value. drained soil. 16 EXPERIMENT STATION BULLETIN 243 (REPRINT) Deepsoils which support anThey can be satisfactorily reseeded abundance of red threeawn can beto other grasses only by plowing or improved by light grazing, tem-by some substitute tillage opera- porary non -use, or winter grazing.tion that gets rid of the threeawn.

PURPLE THREEAWN Aristida purpurea Nutt. Description give the plant a purple color. Growth habit: Perennial bunch- Leaves: Three to 6 inches long, grass in small dense clumps, 1 tosmall, firm, inrolled. 2 feet tall. Seedheads: Open with slender Color: Dark green curing to graybranches that curve or droop with or straw color. In seed, the awnsthe weight of the seed. Seed scales

Figure 11.- Purple threeawn (Aristida purpurea),plant (X%) and seed (X 1). have three awns that are shorterManagement and less divergent than those of Purple threeawn should be graz- red threeawn. ed while growing most actively. As the plants green up in the spring Occurrence morethan manysouthwestern In all counties of Arizona exceptgrasses, they can usually be grazed Navajo, Coconino, Greenlee, andto advantage in March and April. Yuma. It generally grows on rockyMaximum growth occurs in the or sandy plains and slopes at ele-summer, and ranges with an abun- vations between 1,000 and 5,000dance of this grass will be most feet. In the lower portion of itsproductive after the onset of the range itis very common alongsummer rains. roadsides. Like red threeawn, this grass often indicates past range misuse, Forage Value tending to replace the better grass- One of the poorest of our com-es under heavy grazing. Light use, mon range grasses. Palatability istemporary non -use, or winter graz- low, particularly after the plantsing of these areas will give the bet- are mature. ter grasses a chance to increase.

PINE DROPSEED Blepharoneuron tricholepis (Torr.) Nash Description Growthhabit:Fine -stemmed perennial bunchgrass11/2to21/2 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, Ya- vapai, Graham, Gila, Cochise, and Pima counties. This grass common- ly grows in ponderosa pine or Douglas fir forests and open mea- dows at elevations of 6,000 to 10,000 feet. It is sometimes found at much lowerelevationsthoughrather sparsely. Forage Value One of the best forage grasses in timbered areas. Although not as palatable as blue grama, it is con-Figure 12. -Pine dropseed (Blepharon- siderably m o r epalatable thaneuron tricholepis)(X1/4). 18 EXPERIMENT STATION BULLETIN 243 (REPRINT) mountain muhly with which it fre-most part from July through Sep- quently grows. tember. Livestock graze itspar- ingly when it is dormant. About Management one third of the seed stalks should Because pine dropseed growsbe left at the end of the grazing primarily on high -altitude summerseason for seed production and to ranges it should be grazed for themaintain plant vigor.

SIXWEEKS NEEDLE GRAMA Bouteloua aristidoides (H.K.B.) Griseb. Description reasons why this grass is rated as Growth habit:Short -lived an-poor forage. In addition, it has a nual grass, 2 to 15 inches tall. much shorter growing season than Color: Light green, curing to athe associated perennial grasses. straw -color. Management Leaves: Thin, 1/16 to 2/16 inches Sixweeks needle grama is pri- wide,flatorfolded, maximummarily a summer annual and is length about 6 inches, sometimesmost valuable during July and with a few long hairs near the baseAugust. It grows to some extent in or extending up the back. the spring but seldom produces Seedheads: Eight to 14 non -comb-much feed at this season. like spikes on the sides of slender This grass is most important on stems. These spikes are loosely at-desert ranges that produce more tached when dry and drop to thebrush than grass. In years of good ground readily. rainfall it supplements the feed ob- Occurrence tained from tobosa grass, brush and Below 6,000 feet on dry mesas,the few other perennial grasses that washes and waste places through-may be present. out the state except in Apache and Many ranchers consider annuals, Navajo counties.Itgrows mosteither summer or winter, as short - commonly where the original standtime feed that must be consumed of perennial grasses has been de-completely at the time they are pleted, or where rainfall is too lowpalatable. Although annuals are to grow perennials. palatable for a short time only, the Forage Value ungrazed plants are not entirely Sixweeks needle grama produceswasted. The unused plant material a small amount of poor quality for-holds moisture on the area and in- age. It yields a low volume of feedcreases moisture penetration, thus that loses most of its nutrient valueimproving conditions so that per- about the time the seeds are shed.ennial grasses may take over. In The plants have a weak root sys-addition, close grazing of the an- tem and as a consequence are easilynuals year after year will reduce pulled up by grazing animals. Theseed formation, and result in a dirt on the roots is objectionable toshortage of even this feed in later livestock and is one of the majoryears. COMMON ARIZONA RANGE GRASSES 19 SIXWEEKS GRAMA Bouteloua barbata Lag. Description Growth habit:Short -lived an- nual 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 grass is often confused with Rothrock grama. Color:Light green, curing to straw color. Leaves: Few; 1/2to 11/2 inches long, 1/16 to 2/16 inches wide. Four tosevenpersistent,comb -like spikes are borne along the sides of the slender stems. These are characteristic comb -like g r am a spikes, but are smaller than on any of the perennial gramas. Seedheads: Eight to 14 non -comb- like spikes on the sides of slender stems. These spikes are loosely at- tached when dry and drop to the ground readily. Occurrence Almost statewide below6,000 feet. This grama grows most com- monly on open, rocky, or sandy slopes and washes, and on bare - soil areas or where other vegeta- tion is sparse. 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 al- most worthless as forage after ma- Figure13..-Sixweeks needle grama (Bouteloua aristidoides), plant (Xs),turity. The plants have a weak root spike with two spikelets, and lowersystem and pull up easily when spikelet (X 1) . grazed, a feature that makes them objectionable to grazing animals. 20 EXPERIMENT STATION BULLETIN 243 (REPRINT) Management SPRUCETOP GRAMA Ranges supporting an abundance Bouteloua chondrosioides of summer annuals and few per- (H.B.K.) Benth. ennial grasses reach a productivityDescription peak within a few weeks after the Growth habit: Small perennial first summer rains. They remainbunchgrass, 10 to 18 inches tall. productive for one or two months, Color: Bright green, curing to a and then rapidly deteriorate. gray -white. Such ranges often can be stocked Leaves: Short, narrow, and curv- heavily during short periods whened, but not curled as in slender the plants are green. 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 pull- ed from the stem and placed point up they rather resemble tiny spruce trees with drooping branches. They drop from the stem when mature. Occurrence Rather common in Cochise, Santa Cruz and Pima counties at eleva- tions between 2,500 and 6,000 feet. This grama occurs most commonly on dry rocky slopes and rolling desert grasslands with fine -tex- tured 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 palata- ble during the summer rainy sea- son. 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 itis abundant are Figure 14.- Sixweeks grama (Boute-well suited for use during the dor- loi!a barbata) (XY ). mant season. COMMON ARIZONA RANGE GRASSES 21 When grazed during the grow- SIDEOATS GRAMA ing season at least one third of the Bouteloua curtipendula seed stalks should be left for seed (Michx.) Torr. production and to maintain plantDescription vigor. When grazed after the plants Growth habit: Medium -size per- have matured, no more than oneennial bunchgrass, 15 to 30 inches fourth of the seed stalks need re-tall, or occasionally taller. This is main. 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 compara- tively stiff, mostly basal. Seedheads: Ten to thirty small, non -comb -likespikesareborne along the side of each central seed stalk. These spikes drop when ma- ture, 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 com- mon below 2,500 feet, it does ex- tend considerably lower than this where moisture conditions are fav- orable. Forage Value This is one of our most important range grasses. Although not as pal- atableas some ofthesmaller 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 pal- atability. It remains green later in the fall and usually begins growth in the spring before the other gramas. It cures well, and main- Figure 15.- Sprucetop grama (Boute-tains a fairly high feeding value loua chondrosioides) (X1). throughout the year. 22 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 16.- Sideoats grama (Bouteloua curtipendula), plant (Xi /Z) and spike - let (X 1).

Management grass now produce little. Reduced Sideoats grama is not as resistantforage production, carrying capa- to grazing as blue grama. This maycity, and cattle gains have resulted. be because sideoats stays green Sideoats is a normal component longer and is grazed for a longerof most Arizona grassland ranges, period. Many ranges that formerlyand these ranges are not in excel- produced large amounts ofthislent condition without an abund- COMMON ARIZONARANGE GRASSES 23 ance of the grass. It lengthens theranges under good management. grazing season and increases for-Practices that will bring the grass age production, in addition to pro-back include moderation in graz- viding variety in the feed. ing, occasional summer rest, and Sideoatswillreturnto mostbrush control. BLACK GRAMA Bouteloua eriopoda Torr. Description Growth habit: A tangled peren- nial 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, in- rolled, wavy. Seedheads: Four to five, occas- ionally 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 grassgrowsinlargepatches, spreading by above -ground stems that droop to the ground and take root. Occurrence Throughout most of the state be- tween 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 stillFigure17. -Black grama (Bouteloua fairly common over much of itseriopoda)(X1/4). range. Forage Value stems are usually green even when Black grama is one of our bestthe plants are not actively grow- and most nutritious grasses. It pro-ing, a feature that makes this grass duces an abundance of forage thatparticularly valuable as winter for- remains palatable and nutritiousage. throughout the year. Although lessManagement palatable than most gramas dur- Black grama is readily damaged ing the summer growing season, itby heavy grazing during the sum- cures well and provides excellentmer growing season. During the fall, winter, and spring feed. Thefall, winter and spring, when it is 24 EXPERIMENT STATION BULLETIN 243 (REPRINT) most valuable as forage, it is less As black grama is a sod grass it easily harmed. Ranges on whichspreads largely by runners. Since black grama is a major componentproduction of viable seed is low, it of the vegetation should be reserv-is difficult to re- establish once it ed for winter range if possible. has disappeared from a range.

SLENDER GRAMA Bouteloua filiformis (Fourn.) Griffiths

Description Growth habit: Small, fine -stem- med 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, Pi- nal, 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 pal- atable even when dry. Figure 18.- Slender grama (Bouteloua filiformis) (X1). Management Slender grama stands up well under moderate grazing. It with- stands close grazing when this is not continued for too long a period. COMMON ARIZONA RANGE GRASSES 25 BLUE GRAMA Bouteloua gracilis (H.B.K.) Lag. Description Many Arizona ranges, however, Growth habit: A low -growingeven where this grass is abundant, perennialbunchgrassthatfre-do not provide these conditions. On quently grows thick enough tosome thesoiliscompacted, on form an open sod. Usually 6 to 12others, as in the higher mountains, inches tall, but the seedstalks oc-temperatures are low, and blue casionally reach a height of 4 feetgrama produces very little feed. or more. Under these conditions, it is an in- Color: Grayish -green, curing toferior forage plant, not because of gray or straw yellow. reduced palatability or nutritious- Leaves: Fine, of variable length,ness, but because it produces less sometimes curled or inrolled andforage than other grasses would borne close to the ground. under the same conditions. Seedheads: Seeds are borne on two(occasionally one, three or four) comb -like spikes per seed stalk.These headsaretypical comb -like grama spikes, straight or slightly curved and usually hair- less. 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, blueFigure 19. - Blue graina (Bouteloua grama produces abundant forage.gracilis)(X3/4 ). 26 EXPERIMENT STATION BULLETIN 243 (REPRINT) Management ing the growing season, moderate Blue grama is exceptionally re-grazing, and proper distribution of sistanttolong- continued, heavystock are good management prac- grazing. Although more palatabletices for blue grama or for any than many grasses that grow withother grass. it, blue grama may remain as the Blue grama frequently becomes sole occupant of an area because ofsodbound, particularly on fine -tex- its ability to withstand grazing. tured soils or after heavy grazing In spite of its ability to persistand trampling. When this occurs, under heavy use, blue grama bene-forage production may be increased fits from the same managementby opening the sod with a chisel or that benefits other dryland grasses.eccentric disc to permit greater Occasional grazing deferment dur-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 me, 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 some- times coiled into a complete circle. There will usually be a slender needlelike point that extends be- yond each separate spike. Occurrence Reported from all counties, ex- cept 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 withFigure 20.- Hairy grama (Bouteloua blue grama.Itcures well and,hirsuta) (X%). COMMON ARIZONA RANGE GRASSES 27 though not as nutritious as bluetious during the summer grazing grama after curing, it still is oneseason, heavy use atthis time ofthe mostpalatableArizonaweakens the plants and reduces the range grasses. stand. Further, the curing quality Management of this grass makes it better suited Ranges with a large amount ofthan most grasses for use when hairy grama should in most casesdormant. Adjacent areas, where be used primarily for fall, winter,grasses that cure poorly predomin- and spring grazing. Although theate, should be grazed during the grass is most palatable and nutri-growing season.

ROTHROCK GRAMA Bouteloua rothrockii Vasey Description Growth habit: Short -lived, per- ennial 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, Gra- ham, Pinal,Cochise, Pima, and Santa Cruz counties, mostly be- tween 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 onbetter rangelands as the more palatable grasses have disappeared. Figure 21.- Rothrock grama (Boute- Forage Value loua rothrockii) (X1). Rothrockgramaispalatable when actively growing, though less nutritiousthanmostperennialwell and rates only fair in palata- grama grasses at the same stage ofbility and nutritive value when growth. This grass does not curedry. 28 EXPERIMENT STATION BULLETIN 243 (REPRINT) Management will be replaced by better grasses Ranges where this is the princi-under proper range management. pal grass should be grazed primar-It is very susceptible to drought, ilyduring the summer monthsand its abundance may fluctuate when actively growing. On mostwidely from year to year, depend- grassland ranges Rothrock gramaing on weather conditions.

FRINGED BROMEGRASS Bromus ciliatus L.

Figure 22.- Fringed bromegrass (Bromus ciliatus) (X%) COMMON ARIZONA RANGE GRASSES 29 Description Forage Value Growth habit: An erect peren- This is one of the most palatable nial,ratherslenderbunchgrassgrasses in the state. Although it with a well -developed root system.seldom grows in thick stands, it is Stems are usually 1% to 3 feet tall.sufficiently widespread to be an im- Color: Bright green in moderateportant forage species on many of shade or in the open, ranging toour forest ranges. Cattle, horses, light green in dense shade. and sheep, as well as deer and elk, Leaves: One- quarter to % inchgraze this grass readily throughout wide, generally 6 to 10 inches long,the summer. Sheep are particularly essentiallyflat, somewhat roughfond of the developing seedheads. and hairy on the upper surface. Seedheads: Four to12 inchesManagement long. Individual spikes are droop- Because itis so palatable this ing on slender stems. bromegrassisfrequently grazed Occurrence too closely. To get the most out of Reported from Apache, Coconino,it year after year, about one -third Yavapai, Graham, Gila, Cochise,of the seed stalks should be left and Pima counties, generally atevery year. Because this is one of elevations of 6,000 to 10,000 feet.the most sought -after grasses on This is largely a grass of forestedmany summer ranges,itwould areas and does best in open timberbenefit from deferment about every stands or in clearings. third year.

CHEATGRASS Bromus tectorum L. Description Occurrence Growth habit: Annual, generally Primarily in the northern part germinating in the fall and matur-of the state, being reported from ing the following spring, or ger-Navajo,Coconino,and Yavapai minating during the summer rainycounties, but is extending its limits season and maturing by early fall.southward.This weedy annual, Extremely variable in height, ma-which was introduced from Europe, ture plants ranging from 5 or 6is most abundant along highways inches to 2 feet. and railroads but is rapidly spread- Color: Light green when grow-ing into adjacent pinyon -juniper ing -often purple at maturity andand ponderosa pine rangelands. generally a light straw yellow afterForage Value the plants have died. During years of favorable preci- Leaves: Two to 4 inches long,pitation cheatgrass isa valuable flat, and covered with soft fineforage plant. Like all annuals, how- hairs. ever, it is entirely dependent on the Seedheads: Open, with the in-currentyear'sprecipitationfor dividual flower heads drooping ongrowth and may be almost worth- slender stems. less in drought years. In good years 30 EXPERIMENT STATION BULLETIN 243 (REPRINT) the plants produce an abundance of feed but this tends to be washy. Analyses of cheatgrass hay indicate that it has only one -fifth the diges- tible protein content of average al- falfa hay. Management Because cheatgrass matures rapidly and loses much of its food value on drying, grazing should be concentrated during the few weeks when it is most actively growing. Unless very heavy grazing is con- tinued for several years, enough seed normally matures to assure a good stand the following year.

FEATHER FINGERGRASS Chloris virgata Swartz Description Growth habit: A weedy, annual bunchgrass with weak, spreading stems and a shallow root system. Color: Light green when grow- ing; light straw color when dead. Leaves: Flat or folded, thin, and rather weak, with few or no hairs. Seedheads: Several slender fea- thery branches 1 to 3 inches long, radiating fingerlike from the end of a slender, erect stem. Occurrence A common roadside and waste- land 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 Figure 23.- Cheatgrass (Bromus tecto- Because of its local abundancerum) (X1). this grass is valuable as forage in some locations. Like other annuals,though feather fingergrass is fine- however, it produces abundantlyleaved and soft -stemmed, its pala- only after good rainfall seasons ortability is low. Livestock will graze where it receives extra moisture asit but much prefer the perennial runoff from adjacent areas. Al-gramas when available. COMMON ARIZONA RANGE GRASSES 31

Figure 24.- Feather fingergrass (Chloris virgata) (X1/2).

Management grazedrathercloselywithout Feather fingergrass grows rapid-harming the next year's crop. Very ly, and, like most of our annualoften the best management consists grasses, appears to set seed abund-of reseeding stands of this grass antly. For these reasons it can bewith good perennials. 32 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 25.- Bermuda grass (Cynodon dactylon), plant (X%) and spiklet (X 10).

BERMUDA GRASS Cynodon dactylon(L.) Pers. Description four or five very narrow branches Growth habit: A low- growingthat spread fingerlike from the tip sodgrassthatspreads by bothof short leafless stalks. above -groundand below -ground stems. Occurrence Color: Variable green to yellow Throughout the state but most green, curing to straw color aftercommon in the southern portions frost. and in irrigated areas, along stream Leaves: Usually short, flat, andbanks, or where moisture accumu- narrow. lates. This is the principal lawn Seedheads: Seeds are borne ongrass in southern Arizona. COMMON ARIZONA RANGE GRASSES 33 Forage Value Management Bermuda grass is primarily val- Bermuda grass is hard and wiry uable as an irrigated pasture grass,and should be grazed rather close- but frequently provides abundantly. It stands up exceptionally well feed in cienegas or along streamunder long- continued moderately banks. It is relished by all classesheavy use.Irrigatedpastures of livestock, and where moistureshould not be grazed while being is available, it grows through theirrigated or while the ground is spring, summer, and fall months.still soft and muddy. Periodic fer- Animals make their best gains ontilization once a year with a high - Bermuda grass when it grows in-nitrogenfertilizerwill maintain termixed with bur clover or someforage yields which otherwise will other legume. generally decrease. DESERT SALTGRASS Distichlis stricta (Torr.) Rydb. Description Forage Value Growth habit: A low -growing, Although rather harsh, desert rather harsh sodgrass with tough,saltgrass is usually rated as fair scaly, creeping rootstocks. to good forage becauseitstays Color: Blue -green to gray -green.green when most other grasses are Leaves: Sharp, folded or inrolleddry. for part of their length; rather stiff. Seedheads: Erect from the creep-Management ing rootstock, borne on short stems Growing, as it does, on subirri- usually 4 to 15 inches tall. Thegated soils,desert saltgrass can heads frequently become yellowishgenerally be used to best advantage as the seeds mature. during the spring and fall drought Occurrence periods when most of the upland Most common in Apache, Navajo,grasses are dry. As it generally Coconino, Pinal, Yuma, Cochise,grows along streams or around and Pima counties. Usually foundsprings, seeps, or other local wet on subirrigated alkali flats or onspots this grass is usually grazed alkaline soil near springs or streamas long as it is green. For best pro- beds. In Arizona it rarely occursduction, however, it should not be above 6,000 feet. grazed closely the year around. WOOLY BUNCHGRASS Elyonurus barbiculmis Hack. Description ed; usually without hairs but some- Growth habit: A per e n n i a ltimes with a few soft spreading bunchgrass generally about 18 in-hairs on the upper surface. ches to 2 feet tall. Seedheads: Slender, round, un- Color: Rather light green, curingbranched;seedswithoutawns; to a dark straw yellow. heads about 2 to 4 inches long, Leaves: Long, narrow and inroll-dense and light green or silvery. 34 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 26.- Desert saltgrass (Distichlis stricta), plant (X1) and spiklet (X 10), COMMON ARIZONA RANGE GRASSES 35 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 fairforage 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.

PLAINS LOVEGRASS Eragrostis intermedia Hitchc. Description Growth habit: A moderately coarse bunchgrass, 2 to 3 feet tall, witharatheropen, somewhat spreading growth habit. Color: An intermediate shade of green when growing; after matur- ity the plants dry to a light straw yellow. Leaves: Long and slender, rang-Figure 27.- Woolly bunchgrass (Elyon- ing from 4 to 10 inches long byurus barbiculmis) (X%). 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. Occurrence Seedheads: Open, broadly pyra- Widespread in the upper desert mid- shaped with numerous branch-grassland and oak woodland of es that branch again; 8 to 16 inchesGila, Maricopa, Cochise, Pima, and long and 6 to 12 inches wide. Santa Cruz counties, and has been 36 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 28.- Plains lovegrass (Eragrostis intermedia), plant (X%) and spike - let (X 10). found in Coconino and YavapaiPrior to 1910, when plains love - counties. This grass was originallygrass was still abundant, Professor much more abundant than itisThornber wrote that it was eaten today. Its reduction is probably theby livestock wherever they could result of long -continued grazing.get atit, and that even on the Some of the best stands in the Statesteeperslopesitwas thefirst are at Fort Huachuca. species to be grazed. He noted also Forage Value that it was one of the earliest In spite of its coarseness, plainsgrassestostart growth inthe lovegrass is a good forage species.spring. COMMON ARIZONA RANGE GRASSES 37 Management deferred during July and August Because of its palatability andabout every third year. Because of early greening habit, plains love -its early spring value, ranges where grass is often overgrazed in earlythis grass still remains should be spring. Where possible, it should bemanaged to maintain or increase it.

LEHMANN LOVEGRASS Eragrostis lehmanniana Nees Description Leaves: Two to 6 inches long, Growth habit: Perennial bunch -up to 1 /16 inch wide, rather stiff. grass 18 inches to 2 feet tall. Seedheads: Open, spreading; 3 to Color: Bright green, curing to6 inches long, each of the branches dull yellow. tipped with a small gray seedhead.

Figure 29.- Lehman lovegrass(Eragrostis lehmanniana) (X%). 38 EXPERIMENT STATION BULLETIN 243 (REPRINT) In flower, the numerous, featheryseeding southern Arizona ranges. seedheads give fields of the grass aAlthougheasytoestablishon gray color. adapted sites, it is a special -purpose Occurrence grass rather than a remedy for all An introduction from South Af-range ills. Because it is most valu- rica that has become well establish-able in the spring, this grass should ed on some ranges and along roads,be planted in large, manageable principally in Graham, Pima, andunits adapted to spring use. Cochise counties. This grass has Although this grass is not readily proved to be best adapted to eleva-damaged by grazing, care should tions from 3,000 to 4,500 feet. be given to any Lehmann lovegrass Forage Value seeding. Reseedingisexpensive, The greatest forage value of thisand the grass must be properly grass lies in its ability to remainhandled if it is to repay the invest- green late in the fall, and to greenment. The plants should become up early in the spring. Even thoughwell -establishedbeforegrazing. growth is rapid during the sum-This usually requires two growing mer months, the plants are grazedseasons.Onceestablished,the lightly at that time except whereplantingshouldbemoderately there is a lack of native forage.grazed during the spring. Then, During the spring months it pro-after the native range has made vides good forage and is taken insufficient growth, livestock should preference to the dry native grass-be removed from the lovegrass so es. that it can recover and pxoduce Management seed during the summer. A pro- Lehmann lovegrass has provedgram of this sort should insure a to be the grass best adapted to re-long -lived stand of grass. ARIZONA FESCUE Festuca arizonicaVasey Description elevations of 7,000 to 10,000 feet. It Growth habit:A bunchgrassis most abundant in the north -cen- with a large number of denselytral and northern counties, occur- clustered stems. The wiry seedring rather sparingly southward. stalks on mature plants are usuallyForage Value 2 to 3 feet tall. This is one of the better forage Color: Gray -green to blue -green.grasses of northern Arizona. Al- Leaves: Slender, 10 to 20 inchesthough relatively palatable, itis long, stiff and somewhat wiry withnot taken as readily as blue grama inrolled edges. or June grass. It is a larger grass Seedheads: Usually about 3 to 6than either of these, and produces inches long with several spreadinga large amount of forage. The fact branches. that the plants are at least partly Occurrence green during spring, summer and One of the principal grasses infall adds to their value and pala- the evergreen forests of the state attability. COMMON ARIZONA RANGE GRASSES 39

Figure 30.- Arizona fescue (Festuca arizonica), plant (X%) and spikelet (X 10).

Management which itis sometimes associated. Because of this inability to pro- Arizona fescue stands up wellduce well under heavy use,it under moderate grazing, but tendsshould not be heavily grazed year to go out under close grazing muchafteryearduringthe summer more quickly than blue grama withgrowing season. 40 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 31.- Tanglehead (Heteropogon contortus), plant(X1/3)and seed (X 10).

TANGLEHEAD Heteropogon contortus (L.) Beauv. Description Leaves: Broad, 2/16 to 5/16 in- Growth habit: A coarse, peren-ches wide; creased down the mid- nial bunchgrass 1 to 3 feet tall. dle, and clasping the flattened stem Color: Bright green, curing to aat the base. distinctive orange- brown. Seedheads: Spikelike. Each seed COMMON ARIZONA RANGE GRASSES 41 has a sharp -pointed base and a long,Management coarse awn. At maturity, these Areas in which tanglehead occurs seeds and their awns are black andintermixed with other grasses must twist around each other to form abe managed on a basis of the forage tangled mass. as a whole. Tanglehead will be lightly used on year -long ranges Occurrence because of its low palatability. If it were completely used, most of Primarily on rocky slopes andthe other forage plants would be canyons from 1,000 to 5,500 feet inovergrazed. all counties except Apache, Nava- Rangeson whichtanglehead jo, Coconino, Greenlee, and Mari -makes up a major part of the for- copa. Because of its low palata-age should be used during the bility this grass usually persistsspring months to take advantage longer on heavily grazed rangesof the early growth of the grass. than most of the perennial grasses. Tanglehead has received much attention as a grass for reseeding Forage Value the more arid portions of the desert Tanglehead begins growth earlygrassland,particularlythelow in the spring and at this time isrocky ridges. It is one of the easiest readily eaten by cattle and horses.grasses to establish under condi- It becomes coarse and less palata-tions of low rainfall. The low seed ble as it matures and is rated asproduction, however, and the diffi- poor forage on a year -long basis.culty of cleaning the long -awned Because of its coarsenessit hasseeds make its use in extensive little value for sheep. seeding programs impractical. CURLY MESQUITE Hilaria belangeri (Steud.) Nash Description and Yuma. It usually grows in Growth habit: A small,fine -heavy soils on dry, rocky hillsides leaved sodgrass up to 1 foot tall. or in swales between 3,000and Color: Bright bluish -green when6,000 feet. growing, curing to almost white. Forage Value Leaves:Flat, very fine, 3 to 5 Curly mesquite is one of the most inches long, becoming tightly curl-palatable and nutritousofthe ed as they cure. southwestern grasses. Its high graz- Seedheads: Spikelike, borne ating value and growth habit are the end of slender stalks rarelyindicated by one of the common over 8 inches long. Seedheads con-names -southwestern buffalo grass. sist of groups of chaffy seed whichLike buffalo grass and blue grama, fall at maturity, leaving a zigzagcurly mesquite provides good for- stalk. age when actively growing and Occurrence when cured. As with grasses gen- Locally common in all countieserally, its forage value is highest except Apache, Navajo, Mohave,when green. The principal short- 42 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 32. -Curly mesquite (Hilaria belangeri), plant (X1/3) and spikelet cluster (X 10). coming of curly mesquite isits Even though curly mesquite is small size and consequent smallhighly palatable and nutritious, volume of forage produced. pure stands are seldom as product- Management ive as the original mixed stand. Curly mesquite stands up wellThe original mixed stand produced under grazing. The plant spreadsa greater volume and variety of readily by short, curved runnersforage. Furthermore, by the time that take root and develop newthe other grasses have been grazed plantswheretheytouchtheout, grazing pressure and tramp- ground, or by seed. Under heavyling will have reduced forage pro- grazing, it is one of the last peren-duction of curly mesquite. nial grasses to go out. Solid stands A range with an abundance of of the grass sometimes indicatecurly mesquite should be managed long- continued heavy use. to maintain or bring back high- COMMON ARIZONARANGE GRASSES 43 producing associated grasses, andother grasses are abundant or in- to keep these grasses and curlycreasing, management issound; mesquite in excellent vigor. As awhen they are largely lacking or guide to the range condition, thedecreasing, the stocking load trend should be indicated by high -should be lightened or grazing volume producing grasses, rathershould be deferredoccasionally than by curly mesquite. When theduring the growing season.

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 to 2 inches long1 /16 to 3/16 inches wide; edges usually inrolled. Seedheads: Spikes up to 31/2 in- ches long, composed of groups of chaffy seed. Spikes drop at matur- ity, leaving a zigzag stalk. Occurrence On dry,sandyplateausand broad, open valleys or uplands in Apache, Navajo, Coconino, and Mo- have counties at elevations from 4,500 to 7,000 feet. Forage Value Because ofits 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. Figure33.- Galleta(Hilaria jamesii) Management (X%). Galleta should be grazed duringheavily. It appears to stand up ra- the summer while itis growingther well under close grazing but, since it has almost no value whenlike most grasses, should be rested dry.The grass becomes coarseoccasionally during the growing when it is not grazed and for thisseason when grazed closely year reason should be grazed ratherafter year. 44 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 34.- Tobosa (Hilaria mutica) (X i /z) . COMMON ARIZONA RANGE GRASSES 45 TOBOSA Hilaria mutica (Buckl.) Benth Description forage. Forage value during the Growth habit: A coarse peren-summer is also variable, depending nial bunchgrass 1 to 2 feet tall,upon the amount of old growth growing from a coarse scaly root-remaining on the plants.If old stock. Stems spread out at the base,growth is profuse, cattle will not then curve inward at the top, giv-graze the plant unless forced to it. ing each bunch a pointed appear-Because of its coarseness tobosa ance. Stems are not woolly. Tobosaprovides no better than poor to grows over a wide range of clima-fair feed for sheep even while tic conditions and shows consider-growing. It has no value for sheep able variation in form, dependingafter drying. on conditions under which it grows.Management In the drier portion of its range it Tobosa is fairly resistant to graz- becomes very coarse while at high-ing, probably because of its coarse- er elevations, where moisture isness and low palatability. It should more plentiful, the plants are muchbe used during the summer when smeller and finer. it is green and has its highest for- Color: Dull bluish -green whenage value. A rotation developed in growing, curing to gray. southern New Mexico utilizes to- Leaves: Up to 6 inches long, stiffbosa grass areas during the sum- and harsh, hairless. mer and black grama during the Seedheads: Spikes composed ofwinter. This has maintained the groups of chaffy seeds. These dropblack grama range in top condition at maturity, leaving a zigzag seedand has not materially injured the stalk. tobosa. Occurrence Best quality tobosa grass is ob- Locally commoninYavapai,tained by eliminating as much of Gila, Mohave, Graham, Yuma, Co-the old growth as possible, which chise, Santa Cruz, and Pima coun-may be done by heavy grazing, ties at elevations from 2,000 to 6,000burning or haying. Heavy grazing feet. In the lower or more southernwill keep the old growth down, but parts of its range, tobosa grows onmay injure the stand because of fine -textured soils in swales thatclose use during the growing sea- receive runoff water. Farther northson, trampling, or both. Burning or at the higher elevations it occursevery third or fourth year during typically in fine -textured soils onlate winter or early spring has dry rocky hillsides or mesa tops. been satisfactory on many areas. Forage Value Grazing should be deferred on The forage value of tobosa grassburned areas until a satisfactdry varies from good during the sum-growth has been made after the mer months when itis green tofire. On the Jornada Experimental verypoorduringthewinterRange in New Mexico, the grass months, when it becomes harsh andhas been cut for hay with good wiry and loses most of its value assuccess. If cut at the proper time 46 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 35. -Big galleta(Hilaría rigida)(X1/2). COMMON ARIZONA RANGE GRASSES 47 tobosa yields about a quarter tonflats, draining off water that should of high quality prairie hay perbe stored in the soil. In order to acre, more than enough to pay forprevent death of the grasses, gullies the operation. should be checked as soon as poss- In many desert areas, the swalesible. Erection of dams with spread- that produce tobosa grass deter-er wings frequently increases the mine the carrying capacity of thearea flooded and thus promotes area. Practices that will maintaingrowth of tobosa forage. These or increase water spreading willdams will also supply stock water increase the stand of tobosa onduring times ofstress,a much such sites. neededimprovementon many Gullies frequently start in tobosadesert ranges.

BIG GALLETA Hilaria rigida(Thurb.) Benth. Description sand dunes in the hot, dry south- Growth habit: A large, coarse,west corner of the state. almost woody perennial bunch -Forage Value grass, 1 to 3 feet tall. Stems are Big galleta makes fair forage for woolly at the base. cattle and horses when actively Color: Dull bluish -green whengrowing. When dry it has no forage growing, curing to gray or a dirtyvalue. white. Leaves: Coarse, nearly straight,Management and fairly wide, the edges some- Ranges where this grass provides times rolled. Leaves attached bothmost of the feed should usually be at the base of the plant and alonggrazed during the early spring and the upright stems that bear thesummer months while the plants seedheads. Leaf blades may beare growing. As it occurs rather partly covered with short, light,extensively in the western part of woolly fuzz. the state where winter rainfall Seedheads:Spike composed ofusually exceeds summer rainfall, it groups of chaffy seed which dropmay make most of its growth in at maturity to leave a zigzag seedthese areas in the spring. stalk. Spikes are mostly11/2 to 4 Annuals such as filaree and In- inches long. dian wheat often occur in abund- Occurrence ance on big galleta ranges. During On deserts, plains, sand dunesthe occasional years when these and rocky hillsidesin Mohave,plants are abundant, ranges should Yavapai,Pinal,Maricopa,andbe heavily stocked for a short per- Yuma counties up to an elevationiod to take advantage of this feed. of 4,000feet.This plant growsSome use will be made of the big mostly on clay soils that receivegalleta but this grass should not extra runoff during the summerbe used as an index of the carrying rains. It may be common also oncapacity during these years. 48 EXPERIMENT STATION BULLETIN 243 (REPRINT) JUNEGRASS Koeleria cristata (L.) Pers.

Description Growth habit: A medium to small perennial bunchgrass 1 to 11/2 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 roughon the upper surface; arising largely from the base of the plant. Seedheads: Seed stalks numer- ous, slender, and 1 to 11/2 feet tall. The seedhead is a dense, cylindri- cal shiny spike 11/2 to 6 inches long, % inch wide, tapering at both ends.

Occurrence Moderately abundant in allcoun- ties in the state except Yuma at elevations from about 4,000 to 9,000Figure 36.- Junegrass(Koeleria cris - feet. Although this grass growsontata)(X1/4). nearly all soil types,itis most abundant and makes thebest growth on sandy sites. The grass rarely forms pure stands but isone of the most widely distributed of all western grasses.

Management Forage Value Care must be taken not to over- Junegrass is rated as good foragegraze Junegrass in the spring when for all classes of livestock. Itgreensit first greens up. When the plants up earlier in the spring than mostare grazed during the growing sea- grasses and isoften overgrazedson at least a third of the seed early in the season. It grows moststalks should be left for seed pro- actively and produces the bulk ofduction and to make certain that its feed during the summer afterthe vegetative parts of the plants the rains begin. will not be grazed too closely. COMMON ARIZONA RANGE GRASSES 49

Figure 37. -Green sprangletop (Leptochloa dubia), plant(X %)and spikelet (X 10) . GREEN SPANGLETOP Leptochloa dubia (H.B.K.) Nees Description or folded at the midrib but not in- Growth habit: A coarse, erect,rolled at the edges. few -stemmed perennial b u n c h- grass, usually 2 to 3 feet tall. Seedheads: A single central stem Color:Bluish -greentoratherwith from two or three to as many dark green; the portion of the leafas fifteen slender, flexible drooping blade that encircles the stem oftenbranches. These branches are us- tinged with purple. ually from 11/2 to 5 inches long and Leaves: Usually1/8 to slightlyare well separated on the end 4 to less than 1/4 inch wide, either flat8 inches of the stem. Occurrence atable.It generally grows some- From Greenlee to Yavapai Coun-what sparingly interspersed with ty and south into Mexico; has notother grasses and is not a particul- been reported north of the Mogol-arly valuable forage species. lon Rim or from Mohave or YumaManagement counties. Generally grows at ele- vations from 2,500 to 6,000 feet on Because green spangletop is not open upland sites. an important source of feed on most areas, ranges supporting this Forage Value grass should usually be managed Because of its coarseness greenprimarily to maintain or improve spangletop is only moderately pal-the associated forage species.

Figure 38.- Wolftail (Lycurus phleoides), plant (X1) and spikelet (X 10). COMMON ARIZONA RANGE GRASSES 51 WOLFTAIL (TEXAS TIMOTHY) Lycurus phleoides H.B.K. Description on rocky, open slopes in the upper Growth habit: A small perennialdesert grasslands, chaparral, and bunchgrass, 1 to 11/2 feet tall. Simi-oak woodland. lar in vegetative appearance toForage Value blue grama or hairy grama with Wolftail provides good forage for which it is often associated. all classes of livestock. Although Color: Grayish -green, curing toslightly less palatable than blue a grayish -straw color. grama it is better than most of the Leaves: Mostly in a basal clump,coarser range grasses. Growth oc- fine, usually with white margins. curs largely in summer after the Seedheads: Narrow terminalrains begin, but the plants do green spikes 1 to 3 inches long and 1/4up early in the spring. inch in diameter. Both commonManagement names refer to this timothy -like Because wolftail greens up early, seedhead that resembles a wolf'sranges where this grass is abundant tail. can be used to advantage in the Occurrence spring. The summer growth on this In all counties except Mohave,and associated grasses also makes Maricopa, and Yuma, at elevationsit well -suited to summer grazing. of 4,000 to 7,000 feet. It is foundWhen grazed during both spring occasionally as pure stands, butand summer, use should be light usually grows interspersed withenough to assure setting of a good other grasses. It is most abundantcrop of seed. BULLGRASS Muhlenbergia emersleyi Vasey Description Greenlee, Maricopa, and Yuma. It Growth habit: A large, coarseis found most often growing on perennial bunchgrass 2 to 4 feetrocky slopes and ledges in open tall. stands of oak or pinyon and juni- Color: A rather light green whenper. growing, curing to a light gray. Forage Value Leaves: Long, slender, usually Because of its coarseness, bull - folded and confined largely to thegrass has a low palatability for all base of the plant. classes of livestock. It is taken most Seedheads: Flowers are borne inreadily by horses and has almost no a long plume at the end of a long,value for sheep. Cattle will graze slightly leafy stalk. Plumes are 4itlightly when growth is most to 20 inches long, dense, but ratheractive but show a distinct prefer- loose. ence for other associated grasses. Occurrence Management Rather common on hillsides at B u l l g r ass usually grows on elevations from about 3,500 to 6,500ranges that are grazed during the feet in all counties except Navajo,spring, summer, and fall. As other, 52 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 39.- Bullgrass(Muhlenbergiaemersleyi) (X1k) more palatable,grassesprovideed to maintain these grasses. If use most of the forage on these areas,is heavy on bullgrass, the better the stocking rate should be design-grasses will be killed out.

MOUNTAIN MUHLY Muhlenbergia montana (Nutt.) Hitchc. Description Color: Light green; plants often Growth habit: A dense -growing,appear purplish when seeds are moderately large bunchgrass thatripe. flowers after thesoil has been moistened by summer rains. The Leaves:Thin, often somewhat plants are usually about 1 to 2 feetinrolled,and generallyalittle tall. twisted. COMMON ARIZONA RANGE GRASSES 53 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 spe- cies 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 abund- ance 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, andFigure 40.- Mountain muhly (Muhlen- bergiamontana),plant(X%)and is less palatable than the meadowspikelet (X 10). plants. This, and the natural con- centration of stock around water, almost always results in overuseto make fuller use of the dry up- of the meadows and much lighterland areas and the meadows would use of the upland areas between.have a chance to recover from their Most efficient use of many of ourtypically depleted condition. This high mountain ranges could be ob-would result in an increase in the tained by fencing off the meadows.number of stock that could be run In this way stock would be forcedon both meadows and upland.

BUSH MUHLY(HOE GRASS) Muhlenbergia porteri Scribn. Description base. When ungrazed, the plants Growth habit: A large, weak -form a tangled leafy mass 1 to 3 s t e m m e d,fine, wiry perennialfeet high and 11/2 to 3 feet across. bunchgrass. Stems are leafy for their entire length, branched, bent Color: Purplish -green, curing to at the joints, and knotty at thean over -all buff. Some stems re- 54 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 41. -Bush muhly (Muhlenbergia porteri), plant (X%) and spikelet (X10). main a dull green throughout theOccurrence year. Dry mesas and rocky slopes from 2,000 to 6,000 feet in all counties of Leaves: Short, fine, up to 1/s inchthe state except Apache County. wide. This was formerly one of of the Seedheads: Fine, many- branch-most abundant and important ed, loosely drooping, purplish. Dur-grasses of southern Arizona, but is ing good years the very numerousfound now largely as individual seedheads give the entire plant aplantsunder theprotectionof cobwebby appearance. shrubs. COMMON ARIZONA RANGE GRASSES 55 Forage Value Management Bush muhly is highly palatable Where possible this grass should be allowed to set a full crop of seed to all classes of livestock. It re-during the summer growing season mains green most of the year ifat least every second or third year. sufficient moisture is available. OnDeferment of grazing during July conservatively grazed ranges it isand August every year is recom- utilized chiefly between Decembermended on run -down ranges. As and July, but because of its abilitythere are few stands of this grass to remain green yearlong, it doesthat have not been overgrazed this provide some feed every month ofrecommendation applies to most the year. areas where it grows.

DEERGRASS Muhlenbergia rigens (Benth.) Hitchc. Description Forage Value Growth habit: Large, coarse, per- ennial bunchgrass, 2 to 5 feet tall. Because of its coarseness, deer- Color: Cures to a gray strawgrass makes poor feed for all class- color. es of livestock. It is most palatable Leaves: Coarse, 4 to 20 inchesfor horses and least for sheep. long, the edges usually inrolled,Cattle will graze deergrass while growing almost entirely from thethe plants are growing most rapid- base of the plant. ly but show a distinct preference Seedheads: Flower head is a longfor other grasses. and narrow spike, usually 4 to 15 Management inches long and 1/4 to3/s inch in diameter. Deergrassusuallygrowson Occurrence ranges that are grazed during the Open wooded slopes at elevationsspring, summer and fall. As other from 3,000 to 7,500 feet in all coun-morepalatablegrassesprovide ties except Navajo, Mohave, Green-most of the forage on these areas, lee, Maricopa, and Yuma. Most typ-the stocking rate should be design- ical in open stands of oaks anded to maintain these grasses. If use along gravelly or sandy streamis heavy on deergrass, the better beds. grasses will be grazed out.

RINGGRASS (RING MUHLY) Muhlenbergia torreyi (Kunth.) Hitchc. Description as the plant enlarges. The rings Growth habit: A low- growing,may range in size from several fine -leaved, fine -stemmed sodgrassinches to a few feet across. that tends to grow in rings. These Color:Green tobluish -green, are caused by the center dying outreddish or purplish. The red or pur- 56 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 42.- Deergrass (Muhlenbergia rigens) ( X1/2). COMMON ARIZONA RANGE GRASSES 57 ple cast is given the plants by the numerous seed heads. Leaves: Very numerous, form- ing a crisp, curly cushion, slender to the point of being threadlike, curved rather like a bow and in- rolled at the edges; from 1 to 11 inches long. Seedheads: Usually from 2 to 9 inches long, profusely spreading with fine, almost hair -like branches. The flowerheads are usually pur- plish 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 rapidlyitspalata- bility is low. As the plants mature palatability drops almost to zero.Figure 43.- Ringgrass(Muhlenbergia Because of their low palatabilitytorreyi)(X1/3). and small size,ringgrass plants have very little value as forage.cies and result in consistent weight Management losses in the animals being grazed. Ranges with ringgrass should beRanges with an abundance of this managed to restore the better grass-grass should be rested during the es. Continued attempts to obtainsummer rainy season at least every even a moderate amount of feedother year until the vigor and den- from the ringgrass will in timesity of the better species has clearly drive out all of the desirable spe-improved.

INDIAN RICEGRASS Oryzopsis hymenoides (Roem. & Schult.) Ricker Description Color: Rather dark green when Growth habit: A leafy perennialgrowing, light straw -color when bunchgrass 1 to 2 feet tall. cured. 58 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 44.- Indian ricegrass (Oryzopsis hymenoides), plant (X1 /a) and spike - let (X 10).

Leaves: Numerous, slender, firmround, black, and covered with and tightly inrolled;6 -15 inchesshort white hairs. long; they may be as long as theOccurrence flower stalks. Most common in the northern Seedheads: Six to 12 inches long,part of the state at elevations of very open and widely spreading.3,500 to 6,500 feet in Apache, Nava- Each seedhead has several branch-jo, Coconino, Mohave, Yavapai, and es, each of which in turn divides.Pima counties. Although well adap- Seeds are borne singly at the endsted to sandy soils Indian ricegrass of wavy branches. The seeds areis by no means restricted to such COMMON ARIZONA RANGE GRASSES 59 areas. It frequently grows associat-grazed during the spring to give ed with shadscale and winterfatthe nutritious seeds a chance to de- and is able to withstand moderatevelop. If the plants are grazed close amounts of alkali. early in the season, seed produc- Forage Value tion as well as vigor of the plants This grass is highly palatable towill be reduced. all classes of livestock. It cures ex- ceptionally well and is valued as a Areas supporting an abundance winter feed for cattle, sheep, andof this grass should be reserved horses. The seeds, which stay onfor winter use. Grazing during this the plant, are large and high inseason alone, when the plants are protein. They are responsible to adormant, will tend to maintain considerable degree for the valuethese ranges in top condition. In- of the grass as a winter feed. dian ricegrass, and all grasses, can Management be grazed more closely when dor- Indian ricegrass should be lightlymant than when actively growing.

VINE MESQUITE Panicum obtusum H.B.K. Description Occurrence In all counties except Coconino, Growth habit: A perennial vineyGraham, Pinal, and Maricopa at type of sodgrass. Runners form onelevations ranging from 1,000 to top of the ground. These are round,6,000 feet. This grass usually grows wiry and may be as much as 10 feetin swales, mud flats, lowlands with long. The nodes of these runnersfine -textured soils, and along drain- are swollen, and densely hairy.ages that are irrigated at times by Because of the sod growth habit,flood waters. It extends up into the stands of the grass are often ratherlower ponderosa pine forest but is dense. more common at slightly lower ele- Color: Light bluish -green, cur-vations. ing first to a reddish -straw colorForage Value and finally to a gray tan. Vine mesquite provides fair for- Leaves: Flat to somewhat inroll-age forallclassesoflivestock ed at the edges; hairless or verywhile green, but becomes coarse nearly so; up to 8 inches long;and unpalatable after maturity. It about 1/4 inch wide. rates excellent as an erosion con- Seedheads:Generally3to5 trol plant. inches long. Each seedhead consistsManagement of two to six 1 -inch long branches, Vine mesquite should be grazed closely appressed to the main stem.during the summer while actively The large, blunt seeds are bornegrowing because the stems and along these branches. leaves are coarse and lose much of 60 EXPERIMENT STATION BULLETIN 243 (REPRINT) their palatability on drying. As thisheavily grazed. Light grazing gives grass grows in areas that are sub-the runners an opportunity to grow ject to erosion, it should not beand permits the plants to spread.

Figure 45. -Vine mesquite (Panicum obtusum), plant (X %) and spikelet (X 10). COMMON ARIZONA RANGE GRASSES 61 MUTTONGRASS Poa fendleriana (Steud.) Vasey Description Growth habit: A medium -size bunchgrass usually 1 to 2 feet tall. Basal diameter of individual bun- ches 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 com- pact; generally erect rather than nodding.

Occurrence Figure 46.- Muttongrass(Poa fendle- riana),plant (X1 /4) and inflorescence Common on well- drained soils in (X 1). open woodland and forested areas throughout the state at elevations of 5,000 to 11,000 feet. Management Forage Value Because of the forage value of this grass, ranges with moderate or One of the better forage grassesabundant amounts of it should be in the higher portions of the state; particularly valuable as summermanaged to improve or maintain sheepfeed.Muttongrassstartsthe stand. At least one -fourth of growth in late winter or earlythe year's production of seed heads spring and provides an abundanceshould be left by the time growth of good early feed. It rates as ex-begins the following summer. Run- cellent for cattle and horses anddown ranges should not be grazed good for sheep. The foilage cures rather well, and rates as fair fallduring July and August in alter- forage, though less palatable thannate years to give the plants a during late spring and early sum-chance to set seed and to increase mer. vigor. 62 EXPERIMENT STATION BULLETIN 243 (REPRINT) KENTUCKY BLUEGRASS Poa pratensis L. Description Growth habit: A low- growing sodgrass spreading from under- ground rootstocks. The erect flowering stems are 1to 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, usual- ly five in a whorl. Base of individ- ual flowers has cobweb appearance. Occurrence Throughout the state except in the low, drier areas. A common lawn and pasture grass at higher elevations. Figure 47.- Kentucky bluegrass(Poa Forage Value pratensis) (XV4). One of the most palatable grass- es while green. Grows early in theat least once yearly. Where heavily spring and provides good forage forgrazed, two or even three applica- early grazing. This is usually con-tionsarerecommended. When sidered to be the most valuablemoisture is adequate, low produc- pasture grass in North America.tion from Kentucky bluegrass can Although not the most valuableusually be traced to low soil fer- grass in Arizona, it does providetility. large amounts of feed in irrigated Maximum returns on fertilized pastures and in the timbered por-irrigated bluegrass pastures can be tions of the state. realized when two or three pas- Management tures are grazed in rotation. This Kentucky bluegrass withstandsmakes it possible to keep stock off long- continued, heavy grazing bet-each pasture after irrigating while ter than most grasses. For maxi-the ground is still muddy. It also mum returns under irrigation itpermits the grasses to reach a mod- should be fertilized with ammon-erate height before again being ium phosphate or amonium nitrategrazed. COMMON ARIZONA RANGE GRASSES 63

Figure 48.- Plains bristlegrass (Setaria macrostachya) (X%). A drawback to Kentucky blue-mid -summer. Adequate irrigation grass is that it grows slowly for aand fertilization reduce this semi - period of two to four weeks duringdormant period to a minimum. PLAINS BRISTLEGRASS Setaria macrostachya H.B.K. Description Leaves: Six to 16 inches long, 1/s Growth habit: A perennialto % inch wide, rather thin, some- bunchgrass, 1 to 4 feet tall; thewhat rough and hairy on the upper stems often bending abruptly atsurace. As they mature, they be- the nodes. come inrolled and curly. Color: Bright green when grow- Seedheads: Narrow cylindrical ing, curing to orange- brown. spikes 3 to 6 inches long that re- 64 EXPERIMENT STATION BULLETIN 243 (REPRINT) semble ragged seedheads of timo-tected from grazing. Even with this thy, but are bristly with stiff hairsprotection cattle crowd into the extending from between the seeds.bushes to eat it. Occurrence Widespread and abundantin Because of its high palatability, southern Arizona; reported frombristlegrass is selectively grazed to all counties except Apache and Mo-the detriment of the grass. Al- have. This grass is most abundantthough providing excellent forage, on dry plains, rocky slopes, andit will not tolerate heavy use. If a along washes, often in partial shaderange is grazed lightly enough to of shrubs and trees, mostly at 3,500maintain and increase this grass, to 5,500 feet. full use will not be made of the Forage Value other species. If full use is made Plains bristlegrass is a perennialof other species, the bristlegrass bunchgrass with good to excellentwill decrease. Management, there- forage value. The abundant, ten-fore, depends on the percentage of der, basal leaves are highly palata-the grass cover made up of bristle- ble and are readily taken by allgrass. Where it is relatively abund- classes of livestock. ant, management should be for its Management maintenance. Where other peren- Bristlegrass is not very resistantnial grasses provide most of the to grazing. It usually grows in thefeed, management should be de- open shade of low trees or clumpssigned to maintain or improve the of brush, where it is somewhat pro-other species.

JOHNSON GRASS Sorghum halepense (L.) Pers. Description arly abundant along irrigation can- Growth habit: A large aggres-als and along the edges of fields sive sod grass, 3 to 6 feet tall, grow-and roadsides. It often becomes an ing from a scaly, underground root-undesirableweedincultivated stock. fields. Color: A rather bright green. Forage Value Leaves: Three -fourths inch wide Johnson grass makes good forage or less; long, wavy; usually smoothfor all classes of livestock but is without hairs; with a thickenedparticularly valuable for cattle and white midrib. horses. It is a productive hay plant. Seedheads: Open, several branch-As the plants are coarse, the best ed, 5 to 20 inches long and 4 to 5quality hay is obtained when the inches wide. Seeds are conspicu-plants are cut in the boot stage of ously black or red. growth. Occurrence When growth is stopped prema- Throughout the state below 5,000turely by drought or frost, prussic feet where moisture is adequate foracid accumulates in the stems and its growth. This grass is particul-leaves. This forage may then be COMMON ARIZONA RANGE GRASSES 65

Figure 49.- Johnson grass (Sorghum halepense) (X%).

highly toxic to grazing livestock.fieldisfirst opened to grazing. When cut for hay, the acid re-These animals should be watched mains in the hay and the toxicclosely for the first twenty -four effects are as severe as when thehours and removed at the first indi- standing grass is grazed. cation of trouble. If no poisoning is observed during this period the Management forage may be assumed to be safe. Management of Johnson grass isLivestock on Johnson grass should largely a matter of preventing poi-always be closely watched, parti- soning. The grass is hardy, resis-cularly during periods of sudden tant to grazing, and is killed onlyweather changes. The most hazard- by extreme drought. ous times are in the spring and fall Only a few animals should bewhen frosts are likely to occur, or turned in when a Johnson grassduring summer drought. 66 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 50.- Alkali sacaton (Sporobolus airoides), plant (X1 /3) and spikelet (X10).

ALKALI SACATON Sporobolus airoides Torr. Description Seedheads: Loose and open, with Growth habit: A coarse, toughwidely spreading branches, 12 to perennial 2 to 31/2 feet tall, growing18 inches long and 6 to 10 inches in large, dense clumps. wide. Color: Pale green with a slightlyOccurrence grayish cast. In all couunties in the state ex- Leaves: Firm and fibrous; up tocept Mohave, Greenlee, Gila, Mari - 18 inches long and about 1/4 inchcopa, and Yuma between eleva- wide. tions of 2,500 and 6,500 feet. It oc- COMMON ARIZONA RANGE GRASSES 67 curs on fine- textured, often alka-should be grazed during the spring line soils of bottomlands and flats,and summer when growth is most and on sandy plateaus and washes.active. Where it grows only as scat- Forage Value tered plants, management should While this grass is growing vig-be aimed at maintaining the more orously it generally rates as fair toabundant forage species. As this rather good forage for cattle andsacaton is less palatable than most horses and poor to fair for sheep.of the grasses with which it grows, When dry, it provides poor foragethese grasses will be overgrazed if for all classes of livestock. It makesfull use is made of the sacaton. In fair quality hay when cut duringorder to obtain proper use of the the bloom stage. more desirable grasses, therefore, Management the sacaton should usually be some- Solid stands of alkali sacatonwhat under -used.

SAND DROP SEED Sporobolus cryptandrus (Torr.) Gray Description ever, but may be encountered on Growth habit: Perennial bunch -a wide variety of soils. grass, 11/2 to 4 feet tall. The stems are erect at the base, but curve atForage Value the top. A ring of stiff, short hairs Sand dropseed varies in palata- encircles the stem at the junctionbility from one region to another. of the leaf blade and stalk. In most of Arizona it is generally Color: Bluish -green curing to aclassed as fair to good feed for cat- light straw yellow. tle and horses and fair for sheep Leaves: Four to 12 inches longwhen green. After it is mature it is and 1/4 inch wide. The old leavespoor forage for all classes of stock. become frayed by the wind andIt begins growth later than most of "flag" out at right angles to thethe grasses with which it grows. stem. Some of the lighter soil areas in Seedheads: Seedheads aresoutheastern Arizona supporta branched but narrow,purplish,mixture of sand dropseed and blue oftenentirelyenclosed by thegrama. Although blue grama has upper leaves. A large number ofthe higher palatability, the sand very small, hard seeds mature indropseed is taken quite readily. late summer. Management Occurrence Sand dropseed will increase Throughout the state betweenunder moderate use on ranges elevations of 200 to 7,000 feet. Aswhere the original perennial grass- its name implies, sand dropseedes have been killed. Under heavy usually grows on sandy areas. It isuse it will also be killed. Because not restricted to sandy sites, how-of its low palatability when dry, , 68 EXPERIMENT STATION BULLETIN 243 (REPRINT)

Figure 51. -Sand dropseed (Sporobolus cryptandrus), plant (X1/3) and spike- let (X 10).

this grass should be grazed duringfully than most grasses. The seeds summer when it is green. are extremely small and many of Sand dropseed has been reseededthem sift down into the soil where on light, sandy soils more success-they germinate. COMMON ARIZONA RANGE GRASSES 69

Figure 52.- Sacaton (Sporobolus wrightii),plant (X1 /s) and spikelet (X 10).

SACATON Sporobolus wrightii Munro Description Leaves: Flat or somewhat inroll- Growth habit: A large, coarse-ed, up to 12 inches long and 1/4 stemmed perennial bunchgrass, 3inch wide. to 6 feet tall, growing in dense Seedheads: Open, loosely branch- clumps that may be up to 2 feet ined with branches stiffly spreading, diameter. 1 to 2 feet long; secondary branches Color: Pale green with a slightlycloselyappressedto pr i m a r y graying cast. branches. 70 EXPERIMENT STATION BULLETIN 243 (REPRINT) Occurrence managed carefully to make full use Generally on alluvial flats andof the forage and to maintain saca- bottomlands subject to flooding. Onton flats in a highly productive sites of this sort it has been foundcondition. These areas can be used in Arizona at elevations of 2,000 tomost effectively by grazing them 6,500 feet in Graham, Pinal, Nava-heavily in the early spring. After jo, Coconino, Cochise, Santa Cruz,the grasses on the higher ranges and Pima counties. have begun togrow,livestock Forage Value should be moved from the sacaton The tender early spring growthflats and kept off until fall. iseaten readily by cattle and Thecoarse,unpalatableold horses. As the plants mature, thegrowth may be removed by burn- leaves and stems become coarseing every three or four years. It is and tough and are eaten only spar-advisable to divide a flat into three ingly. If cut before seed has set andor four parts and to burn one part while the plants are still growing,each year. The plants will suffer sacaton makes fairly good hay. the least fire injury if they are Management burned during the late winter or Because sacaton is a coarse grassearly spring months before growth that grows rapidly, it should bebegins.

ARIZONA COTTONGRASS (COTTONTOP) Trichachne californica (Benth.) Chase

Description Occurrence All the counties of the state ex- Growth habit: A perennialcept Apache. It is most abundant bunchgrass, 1 to 4 feet tall within the southern part of the state, rather hard round stems. largely between elevations of 1,000 Color: Dark bluish- green,.curingto 6,000 feet. Although one of our to gray or straw color. most common desert grasses, it sel- Leaves: Three to 5 inches long,dom forms pure stands but is found flat, 1/8 to 1/4 inch wide. Leaves dointerspersed with other grasses or not clasp the stem firmly, but pullwith burroweed and mesquite. away, exposing a smooth purple toForage Value green internode. Arizonacottongrassresponds Seedheads: Several long, closelyquicklytospring and summer appressed branches 3 to 5 inchesrains, makes rapid growth, and long. Seeds drop from the branchesprovides highly palatable green at maturity, leaving the branchesforage.Its palatability decreases looking somewhat like broomas maturity is reached. The foliage straw. The seed scales are coveredcures well and some stems remain with white silvery hairs that givegreen in winter. These characteris- the entire seedhead a cottony ap-tics make it an important winter pearance. feed. COMMON ARIZONA RANGE GRASSES 71

Figure 53.- Arizona cottongrass(Trichachne californica)(X1/3). Management back rapidly if it is not summer - grazed. During the rest of the year Because cottontopispalatableit stands up well to grazing and its throughout the year, it is frequent-succulent stems provide good for- ly overgrazed. This grass comesage. 72 EXPERIMENT STATION BULLETIN 243 (REPRINT) SLIM TRIDENS Tridens muticus (Torr.) Nash Description Growth habit: A small, peren- nial 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/s inch wide, rolled in at the edges. Seedheads: Seeds are borne in narrow,cocoon -likeclusterson long, thin stalks, leafy for almost their entire length. When imma- ture, 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 paperlikescalesthatpersist throughout the year. Occurrence All counties except Apache, Gra- ham, Greenlee, Navajo, and Mari - Figure 54. -Slim tridens(Tridens mu- copa up to an elevation of about ticus)(X1/4). 5,500 feet. It grows commonly on rockyhillsidesintermixed withManagement shrubs and other grasses. As slim tridens usually makes up a minor portion of the forage on Forage Value a range, management should be Fair to good forage for all classesbased largely on requirements of of livestock. The plants are scatter-the more valuable species. This ed and seldom make up a large per-grass and those associated with it centage of the total forage pro-grow and should be grazed primar- duced on a range. ily from July through September.

FLUFFGRASS Tridens pulchellus (H.B.K.) Hitchc. Description sometimes forming an open sod. Growth habit: A low, densely Color: Fuzzy bluish -green, cur- tufted perennial bunchgrass 3 to 6ing to a grayish -white. inches tall, often with runners and Leaves: Thin and wiry, 1 to 2 COMMON ARIZONA RANGE GRASSES 73

Figure 55.- Fluffgrass (Tridens pulchellus) (XV3) inches long, growing in distinctForage Value groups at the base of the stem and Fluffgrass is one of the poorest at the end of the flowerstalks justforage grasses on Arizona ranges. beneath the seedheads. When young and actively growing Seedheads: Borne on stems thatthe plants are covered with a blu- are leafless from the base of theish -white down that may be objec- plant to just below the seeds. Thetionable to livestock. Later, when seeds form among a bunch ofthe plants mature, the leaves be- leaves at the end of the stem. Thecome harsh, wiry and sharp point- flower parts are densely silveryed. Because of these features fluff- hairy. Seeds usually fall at matur-grass is normally grazed only on ity, leaving a pair of distinct pa-ranges where there is a feed short- pery bracts. age. Management Even moderate use of this low- Occurrence value plant is evidence that too Throughout the state up to anlittle forage is being produced to elevation of about 5,500 feet.Itcarry the number of animals that rarely grows in abundance on pro-are on the range. In this case a re- ductive sites and is a reliable indi-duction in numbers isrequired, cator of areas of low potential pro-both from the point of view of the ductivity. Reseeding is not recom-immediate welfare of the cattle mended on areas that support anand the long -time condition of the abundance of fluffgrass. range. 74 EXPERIMENT STATION BULLETIN 243 (REPRINT) 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 Mag- azine, 1950. 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. Departments of Animal Husbandry and Agricultural Chemistry. Preliminary report on the composition of range forage plants as related to animal nutri- tion. 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. BioI. Sci. Bui. No. 7. January, 1951. Griffiths, D.Native pasture grasses of the United States. U. S. Dept. Agr. Bul. 201. 1915. 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. COMMON ARIZONA RANGE GRASSES 75 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 nutri- tive value of several native and introduced grasses. Mont. Agr. Exp. Sta. Tech. Bul. 418. October, 1943. Morris, H. E., Booth, W. E., Payne, G. F., and Stitt, R. E.Important grasses on Montana ranges. Mont. Agri. 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., 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 composi- tion 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 Expt. Sta. Texas Agr. Exp. Sta., Prog. Rep. 1061. February, 1947. 76 EXPERIMENT STATION BULLETIN 243 (REPRINT) COMMON NAME INDEX

Common Name Scientific Name Page ALKALI SACATON Sparobolus arioides Torr 66 ARIZONA COTTONGRASS Trichachne californica (Benth.)Chase 70 ARIZONA FESCUE Festuca arizonica Vasey 38 BERMUDA GRASS Cynodon dactylon (L.) Pers 32 BIG GALLETA Hilaria rigida (Thurb.) Benth 47 BLACK GRAMA Bouteloua eriopoda Torr 23 BLUE GRAMA Bouteloua gracilis (H.B.K.) Lag 25 BLUE STEM(See Western Wheatgrass) 5 BULLGRASS Muhlenbergia emersleyi Vasey 51 BUSH MUHLY Muhlenbergia porteri Scribn 53 CANE BEARDGRASS Andropogon barbinodis Lag 6 CHEATGRASS Bromus tectorum L 29 COTTON TOP(See Arizona Cottongrass) 70 CRESTED WHEATGRASS Agropyron desertorum (Fisch.)Schult 4 CURLY MESQUITE Hilaria belangeri (Steud.) Nash 41 DEERGRASS Muhlenbergia rigens (Benth.) Hitchc 55 DESERT SALTGRASS Distichlis stricta (Torr.) Rydb 33 FEATHER FINGERGRASS Chloris firgata Swartz 30 FLUFFGRASS Tridens pulchellus (H.B.K.) Hitchc 72 FRINGED BROMEGRASS Bromus ciliatus L 28 GALLETA Hilaria jamesii (Torr.) Benth 43 GREEN SPRANGLETOP Leptochloa dubia (H.B.K.) Nees 49 HAIRY GRAMA Bouteloua hirsuta Lag 26 HOE GRASS(See Bush Muhly) 53 INDIAN RICEGRASS Oryzopsis hymenoides (Roem. & Schult.)Ricker 57 JOHNSON GRASS Sorghum halepense (L.) Pers 64 JUNEGRASS Koeleria cristata (L.) Pers 48 KENTUCKY BLUEGRASS Poa pratensis L 62 LEHMANN LOVEGRASS Eragrostis lehmanniana Nees 37 LITTLE BLUESTEM Andropogon seoparius Michx 8 MOUNTAIN MUHLY Muhlenbergia montana (Nutt.) Hitchc 52 MUTTONGRASS Poa fendleriana ( Steud.) Vasey 61 PINE DROPSEED Blepharoneuron tricholepis (Torr.) Nash 17 PLAINS BRISTLEGRASS Setaria macrostachya H.B.K 63 PLAINS LOVEGRASS Eragrostis intermedia Hitchc 35 POVERTY THREEAWN Aristida divaricata Humb. and Bonpl 12 PURPLE THREEAWN Aristida purpurea Nutt 16 RED THREEAWN Aristida longiseta Steud 14 RINGGRASS Muhlenbergia torreyi (Kunth.) Hitchc 55 RING MUHLY (See Ringgrass) 55 ROTHROCK GRAMA Bouteloua rothrockii Vasey 27 SACATON Sporobolus wrightii Munro 69 SAND DROPSEED Sporobolus cryptandrus (Torr.) Gray 67 SANTA RITA THREEAWN Aristida glabrata (Vasey)Hitchc 13 SIDEOATS GRAMA Bouteloua curtipendula (Michx.) Torr 21 SIXWEEKS GRAMA Bouteloua barbata Lag 19 SIXWEEKS NEEDLE GRAMA Bouteloua aristidoides (H.B.K.)Griseb 18 COMMON ARIZONA RANGE GRASSES 77 Common Name Scientific Name Page

SIXWEEKS THREEAWN Aristida adscensionis L 12 SLENDER GRAMA Bouteloua filiformis (Fourn.) Griffiths 24 SLIM TRIDENS Tridens muticus (Torr.) Nash 72 SPRUCETOP GRAMA Bouteloua chondrosioides (H.B.K.) Benth 20 TANGLEHEAD Heteropogon contortus (L.) Beauv 40 TEXAS BEARDGRASS Andropogon cirratus Hack 8 TEXAS BLUESTEM (See Texas Beardgrass) 8 TEXAS TIMOTHY(See Wolftail) 51 TOBOSA Hilaria mutica (Buckl.) Benth 45 VINE MESQUITE Panicum obtusum H.B.K 59 WESTERN WHEATGRASS Agropyron smithii Rydb 5 WOLFTAIL Lycurus phleoides H.B.K 51 WOOLLY BUNCHGRASS Elyonurus barbiculmis Hack 33