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New
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Native Grasses D. J. Cotter, Agricultural Experiment Station D. T. Sullivan, Agricultural Experiment Station Native grasses can be attractive and functional in a naturalized landscape. They are often insect and disease resistant, and they can be maintained with less water than often used sculptured types such as bluegrass or Bermuda grass. Further, native grasses can aid in stabilizing disturbed areas. Tall growing grass species often make excellent specimen plants alone or with other native plants. Individually, massed, or mixed with native shrubs or vines, native grasses add natural beauty to the landscape and help control erosion. Most of the native species described here are available from commercial nurseries that specialize in native plants. Seed not available commercially must be collected from native sources. Grasses, unless they have underground creeping rootstalks (rhizomes), are difficult to establish from transplants. Direct seeding on a prepared seedbed is the most satisfactory method of obtaining grass stands, Seed cool-season species in the early fall. Warm-season species may be seeded any time between March I and July 15. When they are planted to take advantage of seasonal rains, native grasses are relatively simple to establish. After they are planted, the soil should be kept moist for 7 to 14 days, depending upon the temperature. Once native grass is established, it may require supplemental water if the annual rainfall is less than 15 inches. An application every two to four weeks during the growing season is usually adequate. More frequent applications may produce more growth, but producing a verdant native turf by watering can be more difficult than with traditional species. Normally, mowing after native grasses are established is not necessary. However, even where mowing is practiced, newly established grasses should be allowed to flower before the first cut to encourage seeding. Description of perennial native grass species with potential for landscape use follow. Some are relatively tall; others are short growing. Some are alkali tolerant. There are warm- and cool-season types and those which normally do not need mowing. Selection of specific species or mixtures will depend on the environmental and soil conditions, landscape requirements, and availability of plant materials. Buffalograss [Buchloe dactyloides (Nutt.) Engelm] According to the 1980 New Mexico Turfgrass Survey, there are 300 acres of Buffalograss turf in the state. It is the only native grass identified in the survey. Buffalograss is a warm-season bunchgrass that forms sod. It grows 4 to 12 inches tall in moderately heavy sods, in eastern New Mexico at elevations of 3,000 to 7,000 feet. It is usually found in mixed stands with blue grama and side-oats grama. Sod houses were usually made with this species. Buffalograss and Blue grama (short grasses) adapt to and conditions principally by drying out under moisture stress and becoming dormant. When water is available again, plants revive quickly. It is a low maintenance grass, drought tolerant and tolerant of alkali soils, but it has poor shade tolerance and turns yellow-brown quickly during a dry period when supplemental water is not provided. Buffalograss forms a dense, tough sod with short foliage of grayish-green (sage green) nap that, with occasional water, retains color from late spring to hard frost. The root system is moderately deep. Mowing is not necessary. If the sod is mowed, it should be cut infrequently to a height of 2 to 3 inches. If the planted area is well watered, applications of up to 6 ounces of nitrogen per 1,000 square feet per month will encourage a vigorous attractive turf. Buffalograss is dioecious (sexes on separate plants). The male plants have flowers on tall and showy spikes; the female plants have bur-like flowers on very short stalks. Buffalograss does well on heavy soil, but plantings on sandy soils have been successful in New Mexico. No seed are produced when soil moisture is low. One cultivar adapted in New Mexico is 'Texoka.' If seed are collected for planting, the seed should be collected in a local ecotype, within 150 miles of the planting site. Freshly collected seed have an initial low germination of 10 percent. Germination increases as seed ages. If treated (mechanical scarification), germination may reach 75 percent. Most commercially available seed have been treated. About 2 pounds of treated seed per 1,000 square feet is sufficient to produce a dense sod usually within two months. Since plants spread rapidly by surface stolons, plugs may also be used. Each plug should be about 4 inches square, spaced 3 to 4 feet apart. Planted in this arrangement an area will be covered in two growing seasons. Once established, Buffalograss turf will withstand moderate to heavy wear. Blue grama [Bouteloua gracilis (H.B.K.) Lag.] A fine-textured, warm-season, bunchgrass that forms sod, blue grama grows 6 to 12 inches tall. It is adapted throughout New Mexico and usually occurs on light or shallow soils at elevations of 3,000 to 8,000 feet. Although it greens up slowly in the spring, Blue grama has good tolerance to low temperature, alkali soils, and drought. Blue grama is one of the most important native range grasses of the Great Plains. It will grow relatively tall when irrigated and heavily fertilized. The foliage is fine-textured and grayish-green, curing to gray or straw yellow. Under moisture stress, the foliage dies out quickly and regrows with added water. It can be left unmowed or it can be mowed to a height of 2 to 3 inches. Nitrogen can be applied at a rate of about one-third pound per 1,000 square feet, in the spring after growth begins. Stems bear two flag-like spikes flowering from June to August. Floral spikes curl as seed matures (August to October). Propagation is primarily by seed. 'Lovington' is a cultivar adapted to New Mexico. Good seed viability is retained in storage for about four years. The seed germination is rapid, and seedlings are vigorous. In a landscape, Blue grama is attractive mixed with Buffalograss and Wheatgrasses. Western wheatgrass (Agropyron smithii Rydb.) A cool-season sod-forming grass that grows 12 to 30 inches tall, Western wheatgrass has broad adaptation in New Mexico at elevations of 3,000 to 10,000 feet. It has a vigorous, strong creeping rhizome system that forms a tight, heavy sod. The root system is shallow and extends laterally for 8 feet or more. Western wheatgrass is moderately tolerant of alkali, and has good drought resistance and low temperature hardiness. Because of these features it provides effective protection of the soil from wind and water erosion. The foliage is nearly flat and stiff, blue-green, erect, and rough on the upper surface. It remains succulent until killing frost. Unless watered, it will become dormant in mid-summer. Regrowth begins early in the spring. Propagation is normally by seed. 'Arriba', released by several western states including New Mexico, should be considered for planting if available. Flowers appear from July to August and seed mature by September. Germination of seed is slow, and establishment is difficult. For pure stand, the seeding rate is one-half pound per 1,000 square feet. Western wheatgrass seed is often used in grass mixtures to provide cover for lawn or pasture. The Agropyron smithii var. molle is similar to other types, but has better germination. Other names of Western wheatgrass include Bluestem wheatgrass, Smith's blue joint, Colorado bluestem. Plains lovegrass (Eragrostis intermedia Hitchc.) A warm-season bunchgrass, plains lovegrass grows 24 to 36 inches tall. It is adapted to southern New Mexico at elevations between 4,000 and 8,500 feet. There are 33 species of lovegrasses throughout the United States. The lovegrasses are drought enduring and alkali tolerant. Plants will not form a dense sod, but individual plants form interesting focal points in association with other grasses and native plants. Growth begins early in the spring. Foliage color is light green on acid soils or brown to red on alkali soils, curing to a light yellow. The flowers appear April to September, usually in response to adequate moisture. The seed heads are open, spreading, lacy and broadly pyramid shaped. The seed is dormant for six months or more after harvest. After one year in storage, germination of 70 -percent is common. 'Kuivato', 'Puhuima' and 'A-68' have been released for use in range improvement. Lehmann lovegrass, (Eragrostis lehmanniana should also be considered in areas of New Mexico. Indian ricegrass [Oryzopsis hymenoides (Roem & Schult.) Ricker] A warm-season bunchgrass, Indian ricegrass grows 12 to 24 inches tall. It normally grows on light or rocky soils at elevations of 4,000 to 9,000 feet and occurs in the north and eastern areas of New Mexico. Its foliage is firm, slender, and dark green, curing to a light straw color. 'Paloma', recently released by several western states including New Mexico, should be considered for planting. Plants flower from May through September. The seed heads are widely spreading with a single seed at the ends of the branches. Many seeds are produced on each plant, but only a small portion can be harvested because seed shattering is severe. Seed are sought as food by birds and rodents. There is delayed germination with at least two forms of dormancy. Treatment with sulfuric acid or mechanical scarification helps break one form, and seed aging overcomes the other. Seed should be stored at least one year before being planted. The seeding rate is one pound per 1,000 square feet. Indian ricegrass seedlings are vigorous and can grow rapidly. Despite the problems of seed dormancy, the species makes a valuable addition to the landscape when mixed with other plants. It may be used to accent other native plants. Black grama (Bouteloua eriopoda Torr.) A warm-season bunchgrass that forms sod, Black grama grows 12 to 24 inches tall with widely spreading runners that root at the joints and form plants. Black grama occurs in most regions of New Mexico, usually on sandy, well drained soils of dry hills and mesas up to 7,500 feet. Often it naturally occurs mixed with blue grama. The foliage is short, narrow, and grayish-green. Growth occurs primarily after spring and fall rains, but foliage can be maintained with an occasional supplemental irrigation. Stems carry four to five flag-like, narrow persistent spikes that flower in early October to frost. Seed ripen three to four weeks after flowering. The seed yield is low even under cultivation. Seed germination of about 20 percent has been reported after three to four years of storage. Curly mesquite [Hilaria belangeri (Steud.) Nash.] A warm-season grass that forms clumps or loose sod, Curly mesquite grows 6 to 12 inches tall. It has strong creeping runners that send up numerous shoots. Restricted to dry areas and lower elevations, stands occur naturally in southern New Mexico. Curly mesquite should make a good winter grass in warm areas of the states. The foliage is short, narrow, and bluish-green, curing to almost white. The seed heads are spike-like on short stems. Propagation is by seed or division of clumps. Curly mesquite competes poorly with weeds. Vine mesquite grass (Panicum obtusum H. B. K.) A perennial, warm-season grass that forms loose sod, Vine mesquite grows 12 to 14 inches in height. The top forms small crowns; the stolons often grow 8 to 10 inches in length. The species is best adapted to heavy soils and sites receiving added water. It is used for erosion control and to revegetate disturbed soils where water may collect. While it grows naturally in most areas of New Mexico, it is usually found in small patches of I to 2 acres in the vegas of east-central New Mexico. The foliage is flat, with a light bluish-green color that cures to a reddish-straw. Flowering occurs from May to October. The seed heads are narrow and open with large seed, which are easily stripped by hand. Germination is about 40 percent. Seed must be well dried before it can be stored. Stored seed maintains viability for up to five years. New seed does not germinate as well as seed stored for several months. Side-oats grama [Bouteloua curtipendula (Michx.) Torr.] A warm-season bunchgrass, Side-oats grama seldom forms a sod naturally. It grows 12 to 40 inches tall, the tallest of the grama group, and occurs throughout New Mexico on well drained sandy plains, rocky slopes, and mountain plateaus. The root system is moderately deep and fibrous. The plant is drought enduring and winter hardy but less tolerant of alkali soils and drought conditions than blue grama. Side-oats grama is often found mixed naturally with Blue grama, Buffalograss, and Winter wheatgrass. This mixture could be used in landscapes to great advantage in many areas of New Mexico. Growth begins in mid-spring and continues through summer. The natural growth is attractive, but a stand can be mowed to 21/2 inches to form a weak sod. Side-oats grama seedlings are vigorous, which aids in establishment. The species is relatively easy to establish on severely eroded soils. The foliage is fine-textured, with a bluish-green color that dries to a straw-yellow. Stems bear 10 to 30 small pendent spikes along one side, with tiny red flowers. The seed is produced July I to October 1, depending on the area. Within two weeks after ripening, the seed disperse and are seldom found on the plant. Division of clumps is the usual method of reproduction although seed may be used. If seed is available, a seeding rate of I pound per 1,000 square feet sown in the fall will make a fair stand. Galleta [Hilaria jamesii (Jorr.) Benth.] A perennial warm-season bunchgrass that forms a loose to dense sod, Galleta grows 12 to 14 inches tall. It occurs on moist soils in the northern two-thirds of New Mexico. It has many of the characteristics of curly mesquite. The foliage is coarse, stiff, dull blue green, with the edges often rolled inward. Tough woody rootstalks can be as deep as 6 feet. Flowers occur from May to September. The seed heads are spike-like on short stiff stems. Galleta is also known as James galleta grass. Salt grass [Distichlis spicata (L) Green var. stricta (Torr.) Beetle] A warm-season grass that forms sod, Salt grass grows 6 to 12 inches tall. It is excellent for low, salty lands subject to occasional irrigation. It is found on medium (below 6,500 feet) to low elevations throughout New Mexico. It is probably the most drought enduring and salt tolerant of -all the native grasses. The foliage is low, coarse and stiff and normally green-yellow. With added water the color is gray green. Plants that are plugged or sprigged in grow together to form a sod. Salt grass sod is a dense cover that is tolerant of heavy traffic. The flowers appear from May to October. The few seed heads are borne on short stems and turn yellow at maturity. Reproduction can be achieved by seed but is more commonly done by division. Other names include Spiked saltgrass and Alkaligrass. Species mixing Grass mixtures with complimenting characteristics planted in a landscape increase the period in which some grasses are growing. Under such stress conditions as temperature, water and salinity, the following combinations should provide a satisfactory coverage.
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