Grasses for Hay and Pasture

THERE ARE about six thousand different species of grass.  They are, in the words of Judge Ingalls, the benediction of nature.  They are also, as 20 years of drought, insect plagues, and war have demonstrated, of unmeasured value to agriculture and the Nation’s economic life.

Grass has gained this new importance and versatility from programs of breeding, introduction, and adaptation that a number of men and institutions have carried on. In 1928 the Department of Agriculture started an intensive effort to improve grass and pastures to help control the corn borer. Beginning in 1933, the Soil Conservation Service and the Agricultural Adjustment Administration developed projects to save soil and stabilize farming by planting more land to hay and forage crops.  During the years of drought, special attention was given to the search for hardy, drought-resistant plants of all kinds from foreign sources. We also stressed improvement of grasses by breeding the materials at hand.

Through the Division of Plant Exploration and Introduction we have been extremely fortunate in obtaining a large number of grasses to supplement our native and naturally introduced grasses. Conspicuous examples of this are Sudan grass and crested wheatgrass. Their value and widespread use are already well understood. Many others, brought in more recently, are proving their worth. I give a few examples to illustrate the use that can be made of them under our wide variety of soil and climatic conditions.

Pangola grass (Digitaria decumbens), introduced from South Africa in 1936, has shown promise in Florida. It was first released to farmers by the Florida Agricultural Experiment Station in 1942. It produces little viable seed and must be propagated vegetatively. It is a rapid-growing perennial, withstands grazing well, and is quite drought-resistant, but it is sensitive to frost and has not proved winter hardy north of Florida. More information, however, is needed on its range of adaptation.

Russian wild-rye (Elymus junceus) was first introduced in 1928 from the Soviet Union. It has about the same range of adaptation as crested wheatgrass and can best be compared with it. Failure to produce seed consistently has been its principal weakness and has limited its use to the Northern Great Plains, where it is best adapted.

Intermediate wheatgrass (Agropyron intermedium), another introduction from Russia, has shown considerable promise in the Northern Great Plains and the Intermountain region. The original introduction was a mixture of two species, A. intermedium and A. trichophorum. As a result, it has shown considerable variation. It is less drought-resistant than crested wheatgrass and more drought-resistant than bromegrass.  The South Dakota Agricultural Experiment Station has increased it under the name of Ree wheatgrass.

Turkestan bluestem (Andropogon ischaemum) and Caucasian bluestem (A. intermedius caucasius), also introductions from Russia, show promlse in the Southern Great Plains. They are vigorous, high-producing plants with fair production of seed. Both are finer stemmed and of better texture than our native bluestems.

Three lovegrasses, weeping lovegrass (Eragrostis curvula), Lehmann’s lovegrass (E. lehmanniana), and Boer lovegrass (E. chloromelas), all introductions from Africa, have proved to be valuable. Weeping lovegrass, well adapted to the Southern Great Plains, has been widely distributed, and is the most winter-hardy of the three. Lehmann and Boer lovegrass are promising in semiarid parts of the Southwest, southern New Mexico, and Arizona.

From these examples of introductions and their development it is apparent that we cannot depend entirely on introductions to meet our changing agricultural needs. Plant breeding is essential in developing species and strains for a grass and pasture program adapted to the conditions where it is to be grown.

Objectives in the improvement program vary-within different grasses and regions and include one or more of the folowing: Resistance to diseases, insects, drought, heat, or. cold; seed production seasonal growth; compatibility; recovery value after grazing or mowing; palatability and nutritive value; aggressiveness; and hlgh yield. It must be recognized that the 1mproved characters desired in any particular grass will depend largely upon the climate of the region in which it is to be grown and the purpose for which it is to be used.

Almost 70 different species of grass are included in some kind of selection, improvement, or breeding program conducted by the Department alone or by the Department in cooperation with States or State experiment stations. This program also includes increasing field-selected material of native and introduced species for conservation and soil-improvement purposes. These lines have not necessarily been selected for type, but rather on the basis of regional adaptation. That is an important factor, because even in field-selected material that has been growing for many years under a particular environment there has been some natural selection by processes of the survival of the fittest.

Some examples of different species adapted to broad climatic regions of the United States will illustrate the advantages of improved varieties.

Bromegrass (Bromus inermis) was first introduced into the United States in 1884. By 1890 it had become widely distributed and seemed to find a home on dry lands in the Northern Great Plains and to some extent in the extreme western part of the Corn Belt. The drought of 1934—36 and the demand for a tall grass to grow with alfalfa and other vigorous legumes brought it into prominence in the Midwest. Michigan farmers were probably the first east of the Mississippi to use bromegrass widely with alfalfa. In the early years most of the seed in commercial channels was from the northern United States and Canada; it was well adapted to Michigan and the Northern States but not to the central latitudes. Many failures resulted. Meanwhile, however, some seed had been harvested from old fields in northeastern Kansas and southeastern Nebraska. In field tests this southern-grown seed was found to be better adapted to the central latitudes than that grown in the North.

A certified variety of bromegrass, named Lincoln, was developed by plant breeders in the Nebraska Agricultural Experiment Station and the Department. Foundation seed, which gave similar performance in extensive field-plot tests, was obtained from selected old fields of bromegrass. The oldest of these fields were planted in the late 1890’s with seed distributed by the Nebraska station. Some evidence indicates that this seed was of Hungarian origin in contrast to later introductions from Russia, or of northern origin. Our first tests showed that Lincoln may be grown much farther north than the region in which it has become naturalized, but it is particularly adapted to the central Corn Belt States where its seedling vigor, ease in establishment, and aggressive sod formation make it of especial value for plantings to control soil erosion and as a pasture, hay, or seed crop. We cannot say the same for the poorly adapted strains from northern sources, presumably of Russian origin, which frequently exhibit poor seedling vigor, are difficult to establish on critical planting sites, and produce an open-type sod in the Midwest.

Lincoln bromegrass was named in 1942 and has been increased by farmers under the auspices of the Nebraska Crop Improvement Association and the Nebraska station. Approximately 325,000 pounds of seed were produced by 78 growers in 1945. Much of that seed was sold to farmers in States east of Nebraska, and tests were started to see how it would do in other States and abroad. In other States similar strains of bromegrass are being certified: In Kansas, the Achenbach strain; Iowa, the Fischer strain; and in Missouri, the Elsberry strain. Strains being increased from the old fields in the central latitudes might well be considered identical for the purpose of certification. They are similar in regional adaptation, and in preliminary tests it appears that they are quite well adapted in the North.

Field selections and introductions from foreign sources of northern origin are also available. Some of these are similar in habit of growth to those in Kansas and Nebraska. The Martin strain, a field selection from Minnesota, is an example.

Timothy (Phleum pratense), is another grass from which a number of varieties have been developed by simple selection. The Ohio Agricultural Experiment Station and the Department have developed two varieties, Marietta and Lorain, whose seed is being increased.

Marietta timothy heads, blooms, and matures several days earlier than ordinary timothy. Its early maturity increases its value for aftermath pasture and makes it better adapted to the southern part of the timothy belt, because it is ready for harvest or use before the hot, dry weather. Marietta is a composite of three early selections.

Lorain timothy originated from a single plant selection, and is 8 to 10 days later than common timothy. It is best adapted to northern Ohio and other States in that latitude. In southern Ohio, however, it is doubtful if it would be better than common timothy. Because the slower early growth of Lorain does not depress the growth of clover, better yields have been obtained when Lorain or late-maturing strains have been grown in a mixture with red clover. Lorain timothy is quite resistant to leaf rust.

Two strains of timothy have been developed by Cornell University.  Seed stocks of one are being increased. Cornell 1777 is a medium early, fine-stemmed timothy of medium height. It stays green until maturity.  Cornell 4059 is tall and erect in growth and has medium coarse leafage.  It is not so resistant to rust as 1777.

Orchard grass (Dactylis glomerata) is another introduction that came in with the early settlers. Only in recent years have attempts been made to develop improved strains. Field collections have been made from old fields for selection and hybridization with new improved strains from abroad.

Some of the imported types of orchard grass have been increased or grown for several years in the United States and, no doubt, have lost part of their original characters, either through natural selection or cross-pollination with domestic types. An example is S-143, a strain imported from Aberystwyth, Wales. During its few years in the United States, it has developed into a plant that is tall-growing, a good seed producer, and of medium leafiness. A recent introduction of the same strain from Wales is low-growing, a sparse seed producer, and leafy.

Tall fescue (Festuca elatior var. arundinaceae), a variety of meadow fescue, has been used extensively throughout the United States for a long time. Beginning in 1890, however, meadow fescue came into prominence, and domestic seed production developed in eastern Kansas, western Missouri, and parts of Indiana in particular. Meadow fescue was short-lived and finally fell into disrepute With increased interest in-grassland agriculture, attention was given to these grasses because they were adapted to semiwet land conditions. The first improvement work on them was started in Oregon.

Alta fescue was developed in 1923 by the Oregon Agncultural Experiment Station and the Department, from a 4-year-old stand of tall fescue.  It is long-lived, deep rooted, and has numerous coarse basal leaves.  In Oregon, it is taller, more robust, higher in forage yield, and longer-lived than the ordinary meadow fescue. It is highly resistant to crown rust, Helminthosporium net blotch, and other diseases that seriously attack meadow fescue. Seed is being produced in Oregon and Washington.  The first increase was made in 1932 at the Oregon Agricultural Experiment Station, and by 1936 the first commercial growers had it in production. By 1945 the commercial seed production of Alta fescue in Oregon almost equalled the total domestic production of meadow fescue.

Since the selection of Alta fescue, other strains of the talk fescues almost identical to it have been found growing in other parts of the United States, although they are not in commercial production. In Kentucky a similar strain known as K-31 is under test. At the Nebraska Agricultural Experiment Station another strain was identified as tall fescue and proved to be similar in growth type and habit to Alta fescue.

The principal weakness of this grass as a pasture crop is its coarse, tough leaves. Livestock will graze it, however, when it occurs in mixtures, or even in pure stands if other grasses are not available. Because it has many desirable characters, both for forage and turf purposes, Alta fescue is worth efforts to improve it further.

Hay and pasture crops merit special attention in the South, in view of the demand for a greater production of livestock and the need to adjust the uses of land.

In the South, Bermuda grass (Cynodon dactylon) is the most widely grown grass. Its tendency to spread to cultivated fields has given it a bad name among farmers who grow row crops like cotton and tobacco, but it grows on upland soils of various types and can control erosion.

In 1929 agronomists at the Georgia Coastal Plain Experiment Station at Tifton found a robust plant of Bermuda grass growing in a cotton field near the station. The plant was increased vegetatively and distributed as Tift Bermuda grass. Later, Department workers started an intensive breeding program at Tifton, planting tall-growing strains that had originated from common Bermuda, Tift, and an introduction from South Africa. These were allowed to cross-pollinate naturally.  From these parents seed was collected in 1938, and more than 5,000 single plants were grown for careful study one by one. Of them, 147 of the most promising plants were selected. They were tested further, and among them a superior strain was found. It is now being increased and distributed under the name of Coastal Bermuda.

Coastal Bermuda grass has larger stems, stolons, rhizomes, and longer internodes than common Bermuda. It is also leafier, more tolerant to cold, and resistant to leafspot. Because it produces little or no seed in the Coastal Plains region, it must be increased by vegetative plantings.

A 3-acre nursery of Coastal Bermuda, established in 1943 at the station at Tifton, supplied planting material to more than a thousand farmers in 1944. It is being distributed also by the Soil Conservation Service and other experiment stations in the South. Georgia organized a crop improvement association in 1945, and its members are increasing certified plant material of Coastal Bermuda.

Another new and apparently good hybrid has been named Suwanee.  It is being distributed in Florida where it -has certain advantages over Coastal Bermuda. It will give a larger yield of hay, and it appears to be more productive on poor soils, but will not stand as much cold or close grazing as Coastal Bermuda.

Bahia grass (Paspalum notatum), an early introduction from Cuba and Central America, has several good points as a pasture grass in the South. It is perennial, leafy, and deep-rooted, spreads by short stolons, and grows well on sandy soils.  When it is properly managed, it produces abundant seed, an important factor because seed of most grasses has been produced outside the Southeast or imported from foreign sources.  But because it is not winter-hardy, its use has been limited mainly to Florida and the Gulf Coast area.

Scientists started intensive tests in 1936 on Bahia grass seed collected from different sources in an attempt to find more types good for controlling erosion. Collections were made by State and Federal workers in the field. Other material was obtained by introductions from plant explorers in Central and South America. In the cooperative work at Tifton, at least six types have been found in the material so far studied.  This classification is based largely on growth habits, plant and genetic characters, and winter hardiness. The strains have been identified as Common, Paraguay, Pensacola, Wilmington, Wallace, and Tampa.

Common Bahia represents the type imported from Guba, Central America, and South America. Because it is susceptible to winterkilling, it is at home mostly in Florida and southern Georgia. It has broader and tenderer leaves than the Paraguay, Wilmington, or Pensacola strains.  The Paraguay strain is a smaller-growing type than common Bahia.  The leaves are thicker, narrower, tougher, and darker green in color. It is more frost-resistant and can withstand lower temperatures than common Bahia. The strain was named Paraguay because it was developed from introductions made in 1937 from Paraguay. Since that time samples of Bahia grass seed, which proved to be the same type as Paraguay, were obtained from a grower near El Campo, Tex.

Pensacola Bahia was probably introduced from ballast dumped on land near the old Perdido Wharf at Pensacola, Fla. This strain differs from other strains in many respects, but, like Paraguay, it makes excellent pasture in the spring and early summer, although it becomes tough in late summer. It is an excellent seed producer, but the seed shatters readily and is difficult to save. Observations at Tifton indicate that Pensacola spreads more rapidly than other Bahias and tolerates frost a little better than Paraguay. The most striking genetic difference is in the number of chromosomes. The Pensacola strain has 20 pairs of chromosomes; other strains that were studied cytologically have 40 pairs.

Of the several strains collected by men in the Nursery Division of the Soil Conservation Service, Wilmington Bahia, collected near Wilmington, N. C., is the most winter-hardy. Other strains, but of less importance at this time, are the Wallace and Tampa Bahia.

The largest areas of natural grass and range lands in the United States are in the Great Plains and the Inter-Mountain region, a vast area where the soil is usually productive but rainfall is a limiting factor.  The plant breeder finds there a wealth of material that can be used in a program to improve grass. These grasses can be broadly classified as cool- temperature plants, those that make the most growth during spring and fall, and warm-temperature plants, those that grow best during the summer.

Because the number of desirable grasses in this region is large, I can mention only a few examples to illustrate the efforts to improve them.

Native grasses vary widely in their adaptation. Much of the improvement work therefore has been confined to field selections. Because of variations in winter hardiness, forage production, day length, disease resistance, and other factors, the field selections cannot be moved too far north or south from the region of their origin. Until local tests have proved otherwise, strains we now have should not be planted more than 150 or 200 miles north or south from the area of origin.

Intensive work was started on buffalo grass (Buchloe dactyloides) in 1935. Plant breeders want to domesticate this highly variable plant by selection and hybridization. Because of the wide variation in almost every known character in buffalo grass, selection has been used most extensively. Improvement work has been under way in North Dakota, Nebraska, Kansas, Oklahoma, and Texas—most intensively at Hays, Kans., and Woodward, Okla.

The Hays strain is the only improved one in which seed is available for limited distribution in 1947. It was developed at the Fort Hays Agricultural Experiment Station at Hays, in cooperation with the Department. At least 5,000 pounds of foundation seed were produced for distribution annually at that station in 1944, 1945, and 1946.

The main aim of the workers who developed the Hays strain was to breed a type that bears abundant seed on stems for easier harvesting.  The-strain has been superior to common or field buffalo grass in production of seed and forage. It is said to equal common buffalo grass in resistance to disease, and has the ability to produce seed high off the ground. Other selections of buffalo grass made at the Hays station appear to be even more promising than the Hays strain.

The Southern Great Plains Field Station at Woodward started to increase the seed of three strains of buffalo grass that appeared promising in the preliminary stages of development. One of them gave evidence of being a particularly outstanding cross because it has tall, quick spreading plants bearing.seed on the stalk 6 to 8 inches above the ground. It is an aggressive strain—sprigs set out at 5-foot intervals completely fill in the space between them in about 3 months.

Blue grama (Bouteloua gracilis) is a warm-season, short grass found growing in association with buffalo grass. It forms a good sod, although it is a typical bunchgrass. Many strains of blue grama occur naturally, but southern strains generally lack winter hardiness when they moved north, and northern strains yield less when grown in the South. Seed is hard to get, because blue grama fails to set seed consistently; the development of desirable seed-producing strains is of major importance. So far, it has been impossible to obtain lines either by selection or hybridization that are superior in seed production under irrigation or dry-land conditions. Intensive studies will have to be made to develop strains of this important range grass.

Side-oats grama (Bouteloua curtipendula) is another native, perennial, warm-season grass that ranks high in palatability. It is easily established by seed and forms an important part of the mixture recommended for range land reseedings. Strains from the South are subject to winter in jury when moved north, and northern strains are low in production when moved southward.

El Reno side-oats grama was developed from field collections made near El Reno, Okla. It has ranked higher than other strains tested in Kansas for leafiness, resistance to leaf disease, and seed production.

Switchgrass (Panicum virgatum) is a native long-season grass that grows alongside the bluestems. It resembles other native grasses in growth and adaptation, but it differs from them in that it is a good seed producer, and the seed can be easily harvested, cleaned, and sown.

One strain that is being propagated is known as Blackwell switchgrass in Kansas. It is a field selection from Blackwell, Okla., developed by the Soil Conservation Service at Manhattan, Kans. It has a fine leafy quality and considerable resistance to rust. It matures seed moderately late and yields well. The leaves remain green until frost. In Kansas, and perhaps in nearby States, it is adapted for use in mixtures. It has been accepted for certification by the Kansas Crop Improvement Association. Another field selection, made from Holt County, Nebr., is a small, leafy type that is well adapted to the sandy soils north of the Platte River in Nebraska.  It is susceptible to rust when grown farther south.

Mandan wild-rye (Elymus canadensis) is an improved variety of Canada wild-rye. It was developed at the Northern Great Plains Field Station by mass selection from plants grown from seed collected on upland near Mandan, N. Dak. Several vital characters make it superior to ordinary Canada wild-rye. It is longer-lived than many strains and will withstand grazing for several years. It is leafier, finer, and the softer-textured leaves are shorter. It has more resistance to rust than other strains that have been tested. It is easy to establish, grows rapidly, and yields well in seed and forage. It can be used to good advantage in mixtures with other grasses that are slower in becoming established. It seems to prefer sandy soils, but it also makes good growth on other soil types. Seed of Mandan wild-rye germinates more slowly than that of crested wheatgrass. It often sprouts a week later than crested wheatgrass. Establishment is relatively rapid, but it may take a year before weeds are crowded out.

Feather bunchgrass (Stipa viridula) has given way to green stipagrass, an improved variety that was developed at the Northern Great Plains Field Station from a single plant selection which originated from a bulk seed lot collected near Mandan. We think it is superior to ordinary feather bunchgrass in vigor and size. It excels in yields of forage and seed. In fact, it is one of the highest yielding of the cool-season grasses that have been tested at Mandan since 1942. After defoliation, it makes rapid regrowth and is useful in mixtures for pasture seedings. It is easily established in areas where weed competition is not too great. Hay cut at approximately the time the plants are in full head is nutritious and palatable. It seems to grow well on most soil types and probably can be grown successfully over most of the Northern Great Plains. Green stipagrass begins growth about a week later in the spring than crested wheatgrass. The seed ripens earlier than most species and reaches maturity about 3 weeks ahead of crested wheatgrass. It is of low germination when the seed is new, but if the seed is held in dry storage for 3 years, germination should be satisfactory.

Unfortunately, farmers and commercial seedsmen have not given enough consideration to the production of grass seed, which all too often has been limited to small localities in a few States or has been only a sideline crop, the seed being harvested from old pastures or natural stands.

The value of the 1944 crop of seed, based on the 1930-39 wholesale prices, was estimated to be approximately $20,000,000. Even though the figure is an estimate, it shows that grass seed as a crop is a sizeable business. The bulk of this represents common seed and does not include improved strains. Facilities for production of foundation seed of improved strains are lacking.

Improvement of grasses can be a success only if these new strains reach the farmer in quantity and quality to meet his needs. The plant breeder must cooperate with him and the seed producer to make this possible. The responsibility of testing new strains for regional adaptation and best uses lies with the plant breeder. He must also be certain that the foundation seed is true to type and will maintain the superior qualities of the new strain. Certified seed should be so grown and isolated as to maintain genetic purity. The consumer must know which strain is best adapted to his particular climatic conditions and requirements. The seed producer must grow those seeds in a manner that will assure the consumer of getting the strain and grade he demands. And, finally, the distributor must handle the seed in cleaning, processing, and bagging so as to keep the strains from becoming mixed.

THE AUTHOR
M. A. Hein, an agronomist in the Division of Forage Crops and Diseases, in the Bureau of Plant Industry, Soils, and Agricultural Engineering, joined the Department of Agriculture in 1928, the year he received the degree of master of science in agronomy from the University of Illinois. He is currently engaged in experimental work with native and introduced grasses for hay, pasture, and silage, adaptation studies, breeding for improvement, cultural practices, and other factors relating to grass.

FOR FURTHER READING
Black, W. H,, and Clark, V. I.: Comparison of Native Grasses and Crested Wheatgrass and of Supplements for Beef Cattle in the Northern Great Plains, U. S. D. A. Circular 705, 1944.
Fracker, S. B., Garber, R. J., Myers, W. M., and others: Improving Pastures and Grasslands for the Northeastern States, U. S. D. A. Miscellaneous Publication 590, 1946.