W190 

 CLOVERS 



Trifo'lium spp. 



Clovers, sometimes called trefoils, are annual, biennial or perennial herbs 

 belonging to the large pea family (Leguminosae). The generic name Tri folium 

 refers to the characteristic three-divided leaves. The genus, which includes 

 about 300 species, is widely distributed in all north temperate regions, with 

 a few species occurring on the mountains of tropical Africa, on the Andes, 

 and in subtropical South America and in South Africa. A large number of 

 species are native to the far western range States and grow from about sea 

 level to elevations of 14,000 feet. Clovers are relatively common almost every- 

 where in the western mountains, although most , species do best on moist 

 sites in meadows and along streams. Several species, however, occur 

 abundantly on the open grasslands and in mature timber stands. Some clovers 

 are adapted to grow in poor, dry or poorly drained soils of waste lands. Clovers 

 do best on soils rich in lime and potash. Some of the perennial clovers grow 

 in pure stands and form rather dense sod, which withstands trampling and 

 grazing well. 



Clovers have been cultivated since the sixteenth century and are unexcelled 

 for pasturage and hay, their present total acreage in the United States being 

 nearly five times that of alfalfa. 1 Clover has a high feeding value for young 

 and milking animals, being equal to timothy in digestible nutrients, and con- 

 taining three times as much protein. Most of the native clover species are 

 as palatable as the cultivated forms, but generally they are divided into two 

 groups. Those species which grow on the more moist sites have a palatability 

 of from very good to excellent for all classes of livestock and game animals. 

 On the other hand, thosel species growing on the drier sites rate from fairly 

 good to good in palatability for sheep, but somewhat lower for cattle and horses. 

 Clovers, including several naturalized species from Europe, are quite abundant 

 and are rather important forage plants on the range. 



Cattle and sheep are always liable to bloat from eating green clover, especially 

 if the plants are wet and the animals hungry. However, under normal range 

 conditions, bloating seldom, if ever, occurs. When such animals as horses are 

 pastured upon white clover (T. repent) that has gone to seed, the acrid seed 

 often causes the animals to slobber. This condition is not necessarily harmful. 

 Cases are known where alsike clover (T. hybridum) has caused severe ulcera- 

 tions of the mouth, forelegs, and body of horses and mules a condition known 

 as trifoliosis. There apparently is some evidence that this is caused by a 

 fungus on the clover and not by the plant itself. 2 



Clovers have long been recognized as capable of increasing soil fertility. 

 These plants are able to increase the nitrogen content of the soil from the root 

 tubercles which they bear. Certain bacteria which are able to use free nitrogen 

 of the air live in the root tubercles of the clover plants. After these root 

 tubercles decay this nitrogen becomes available to other plants. The me- 

 chanical action of the long, deep root systems of clovers also improves the 

 tilth of the soil. These roots penetrate deeply into the subsoil making plant 

 food, which is inaccessible to most other plants, available to clover. 



Several species of clovers have been used successfully in range reseeding 

 projects throughout the West. 3 They produce an abundance of viable seed 

 which germinate well even when several years old. Seeds stored for 9 years 

 had a germination percentage of 71.6 percent. 4 The viability of clover seed 

 containing 15 percent moisture, or less, was unaffected by exposure to tem- 



1 Robbins, W. W., and Ramaley, F. PLANTS USEFUL TO MAN. 428 pp., lllus. Phila- 

 delphia. 1938. 



2 Morgan, II. A., and Jacob, M. I. ALSIKE CLOVER, n. ILL EFFECTS SOMETIMES PRO- 

 DUCED ON HORSES AND MULES PASTURED EXCLUSIVELY UPON ALSIKE. Tenn. Agr. Expt. Sta. 



Bull. 18(3) : [22]-30, illus. 1905. 



Forsling, C. L., and Dayton, W. A. ARTIFICIAL RESEEDING ON WESTERN MOUNTAIN 

 RANGE LANDS. U. S. Dept. Agr. Circ. 178, 48 pp., illus. 1931. 



4 McRostie, G. P. LONGEVITY OF ALFALFA AND CLOVER SEED. Sd. Agr. 4(8) : 236-238. 

 1924. 



