From the fact that they do well in so many different sections and in so many different climates, the following are the most useful legumes: alfalfa, clovers, cowpeas, vetches, and soy beans.
=Alfalfa.= Alfalfa is primarily a hay crop. It thrives in the Far West, in the Middle West, in the North, and in the South. In fact, it will do well wherever the soil is rich, moist, deep, and underlaid by an open subsoil. The vast areas given to this valuable crop are yearly increasing in every section of the United States. Alfalfa, however, unlike the cowpea, does not take to poor land. For its cultivation, therefore, good fertile land that is moist but not water-soaked should be selected.
Good farmers are partial to alfalfa for three reasons. First, it yields a heavy crop of forage or hay. Second, being a legume, it improves the soil. Third, one seeding lasts a long time. This length of life may, however, be destroyed by pasturing or abusing the alfalfa.
[Ill.u.s.tration: FIG. 231. SHEEP FATTENING ON ALFALFA STUBBLE]
Alfalfa is different from most plants in this respect: the soil in which it grows must have certain kinds of bacteria in it. These cause the growth of tubercles on the roots. These bacteria, however, are not always present in land that has not been planted in alfalfa. Hence if this plant is to be grown successfully these helpful bacteria must sometimes be supplied artificially.
There are two very easy ways of supplying the germs. First, fine soil from an alfalfa field may be scattered broadcast over the fields to be seeded. Second, a small ma.s.s of alfalfa tubercle germs may be put into a liquid containing proper food to make these germs multiply and grow; then the seeds to be planted are soaked in this liquid in order that the germs may fasten on the seeds.
Before the seeds are sowed the soil should be mellowed. Over this well-prepared land about twenty pounds of seed to the acre should be scattered. The seed may be scattered by hand or by a seed-sower. Cover with a light harrow. The time of planting varies somewhat with the climate. Except where the winters are too severe the seed may be sowed either in the spring or in the fall. In the South sow only in the fall.
[Ill.u.s.tration: FIG. 232. HERD OF DAIRY CATTLE GRAZING ON ALFALFA STUBBLE]
During the first season one mowing, perhaps more, is necessary to insure a good stand and also to keep down the weeds. When the first blossoms appear in the early summer, it is time to start the mower. After this the alfalfa should be cut every two, three, or four weeks. The number of times depends on the rapidity of growth.
This crop rarely makes a good yield the first year, but if a good stand be secured, the yield steadily increases. After a good stand has been secured, a top-dressing of either commercial fertilizer or stable manure will be very helpful. An occasional cutting-up of the sod with a disk harrow does much good.
=Clovers.= The different kinds of clovers will sometimes grow on hard or poor soil, but they do far better if the soil is enriched and properly prepared before the seed is sowed. In many parts of our country it has been the practice for generations to sow clover seed with some of the grain crops. Barley, wheat, oats, and rye are the crops with which clover is usually planted, but many good farmers now prefer to sow the seed only with other gra.s.s seed. Circ.u.mstances must largely determine the manner of seeding.
Crimson clover, which is a winter legume, usually does best when seeded alone, although rye or some other grain often seems helpful to it. This kind of clover is an excellent crop with which to follow cotton or corn.
It is most conveniently sowed at the last cultivation of these crops.
Common red clover, which is the standard clover over most of the country, is usually seeded with timothy or with orchard gra.s.s or with some other of the gra.s.ses. In sowing both crimson and red clover, about ten to fifteen pounds of seed for each acre are generally used.
To make good pastures, white and j.a.pan clover are favorites. White clover does well in most parts of America, and j.a.pan clover is especially valuable in warm Southern climates. Both will do well even when the soil is partly shaded, but they do best in land fully open to the sun.
Careful attention is required to cure clover hay well. The clover should always be cut before it forms seed. The best time to cut is when the plants are in full bloom.
[Ill.u.s.tration: FIG. 233. CRIMSON CLOVER]
Let the mower be started in the morning. Then a few hours later run over the field with the tedder. This will loosen the hay and let in air and sunshine. If the weather be fair let the hay lie until the next day, and then rake it into rows for further drying. After being raked, the hay may either be left in the rows for final curing or it may be put in c.o.c.ks. If the weather be unsettled, it is best to c.o.c.k the hay. Many farmers have cloth covers to protect the c.o.c.ks and these often aid greatly in saving the hay crop in a rainy season. In case the hay is put in c.o.c.ks, it should be opened for a final drying before it is housed.
=Cowpeas.= The cowpea is an excellent soil-enricher. It supplies more fertilizing material to turn into the soil, in a short time and at small cost, than any other crop. Moreover, by good tillage and by the use of a very small amount of fertilizer, the cowpea can be grown on land too poor to produce any other crop. Its roots go deep into the soil. Hence they gather plant food and moisture that shallow-rooted plants fail to reach. These qualities make it an invaluable help in bringing worn-out lands back to fertility.
The cowpea is a warm-weather legume. In the United States it succeeds best in the south and southwest. It has, however, in recent years been grown as far north as Ma.s.sachusetts, New York, Ohio, Michigan, and Minnesota, but in these cold climates other legumes are more useful.
Cowpeas should never be planted until all danger of frost is past. Some varieties make their full growth in two months; others need four months.
There are about two hundred varieties of cowpeas. These varieties differ in form, in the size of seed and of pod, in the color of seed and of pod, and in the time of ripening. They differ, too, in the manner of growth. Some grow erect; others sprawl on the ground. In selecting varieties it is well to choose those that grow straight up, those that are hardy, those that fruit early and abundantly, and those that hold their leaves. The variety selected for seed should also suit the land and the climate.
The cowpea will grow in almost any soil. It thrives best and yields most bountifully on well-drained sandy loams. The plant also does well on clay soils. On light, sandy soils a fairly good crop may be made, but on such soils, wilt and root-knot are dangerous foes. A warm, moist, well-pulverized seed-bed should always be provided. Few plants equal the cowpea in repaying careful preparation.
[Ill.u.s.tration: FIG. 234. COWPEAS]
If this crop is grown for hay, the method of seeding and cultivating will differ somewhat from the method used when a seed crop is desired.
When cowpeas are planted for hay the seeds should be drilled or broadcasted. If the seeds are small and the land somewhat rich, about four pecks should be sowed on each acre. If the seeds are comparatively large and the soil not so fertile, about six pecks should be sowed to the acre. It is safer to disk in the seeds when they are sowed broadcast than it is to rely on a harrow to cover them. In sowing merely for a hay crop, it is a good practice to mix sorghum, corn, soy beans, or millet with the cowpeas. The mixed hay is more easily harvested and more easily cured than unmixed cowpea hay. Shortly after seeding, it pays to run over the land lightly with a harrow or a weeder in order to break any crust that may form.
Mowing should begin as soon as the stalks and the pods have finished growing and some of the lower leaves have begun to turn yellow. An ordinary mower is perhaps the best machine for cutting the vines. If possible, select only a bright day for mowing and do not start the machine until the dew on the vines is dried. Allow the vines to remain as they fell from the mower till they are wilted; then rake them into windrows. The vines should generally stay in the windrows for two or three days and be turned on the last day. They should then be put in small, airy piles or piled around a stake that has crosspieces nailed to it. The drying vines should never be packed; air must circulate freely if good hay is to be made. As piling the vines around stakes is somewhat laborious, some growers watch the curing carefully and succeed in getting the vines dry enough to haul directly from the windrows to the barns. Never allow the vines to stay exposed to too much sunshine when they are first cut. If the sun strikes them too strongly, the leaves will become brittle and shatter when they are moved.
When cowpeas are grown for their pods to ripen, the seeds should be planted in rows about a yard apart. From two to three pecks of seeds to an acre should be sufficient. The growing plants should be cultivated two or three times with a good cultivator. Cowpeas were formerly gathered by hand, but such a method is of course slow and expensive.
Pickers are now commonly used.
Some farmers use the cowpea crop only as a soil-enricher. Hence they neither gather the seeds nor cut the hay, but plow the whole crop into the soil. There is an average of about forty-seven pounds of nitrogen in each ton of cowpea vines. Most of this valuable nitrogen is drawn by the plants from the air. This amount of nitrogen is equal to that contained in 9500 pounds of stable manure. In addition each ton of cowpea vines contains ten pounds of phosphoric acid and twenty-nine pounds of potash.
There is danger in plowing into the soil at one time any bountiful green crop like cowpeas. As already explained on page 10, a process called capillarity enables moisture to rise in the soil as plants need it. Now if a heavy cowpea crop or any other similar crop be at one plowing turned into the soil, the soil particles will be so separated as to destroy capillarity. Too much vegetation turned under at once may also, if the weather be warm, cause fermentation to set in and "sour the land." Both of these troubles may be avoided by cutting up the vines with a disk harrow or other implement before covering them.
The custom of planting cowpeas between the rows at the last working of corn is a good one, and wherever the climate permits this custom should be followed.
=Vetches.= The vetches have been rapidly growing in favor for some years. Stock eat vetch hay greedily, and this hay increases the flow of milk in dairy animals and helps to keep animals fat and sleek. Only two species of vetch are widely grown. These are the tare, or spring vetch, and the winter, or hairy, vetch. Spring vetch is grown in comparatively few sections of our country. It is, however, grown widely in England and northern continental Europe. What we say here will be confined to hairy vetch.
After a soil has been supplied with the germs needed by this plant, the hairy vetch is productive on many different kinds of soil. The plant is most vigorous on fertile loams. By good tillage and proper fertilization it may be forced to grow rather bountifully on poor sandy and clay loams. Acid or wet soils are not suited to vetch. Lands that are too poor to produce clovers will frequently yield fair crops of vetch. If this is borne in mind, many poor soils may be wonderfully improved by growing on them this valuable legume.
[Ill.u.s.tration: FIG. 235. VETCH]
Vetch needs a fine well-compacted seed-bed, but it is often sowed with good results on stubble lands and between cotton and corn rows, where it is covered by a cultivator or a weeder.
The seeds of the vetch are costly and are brought chiefly from Germany, where this crop is much prized. The pods ripen so irregularly that they have to be picked by hand.
In northern climates early spring sowing is found most satisfactory. In southern climates the seeding is best done in the late summer or early fall. As the vetch vines have a tendency to trail on the ground, it is wisest to plant with the vetch some crop like oats, barley, rye, or wheat. These plants will support the vetch and keep its vines from being injured by falling on the ground. Do not use rye with vetch in the South. It ripens too early to be of much a.s.sistance. If sowed with oats the seeding should be at the rate of about twenty or thirty pounds of vetch and about one and a half or two bushels of oats to the acre. Vetch is covered in the same way as wheat and rye.
Few crops enrich soil more rapidly than vetch if the whole plant is turned in. It of course adds nitrogen to the soil and at the same time supplies the soil with a large amount of organic matter to decay and change to humus. As the crop grows during the winter, it makes an excellent cover to prevent washing. Many orchard-growers of the Northwest find vetch the best winter crop for the orchards as well as for the fields.
=Soy, or Soja, Bean.= In China and j.a.pan the soy bean is grown largely as food for man. In the United States it is used as a forage plant and as a soil-improver. It bids fair to become one of the most popular of the legumes. Like the cowpea, this bean is at home only in a warm climate. Some of the early-ripening varieties have, however, been planted with fair success in cold climates.
While there are a large number of varieties of the soy bean, only about a dozen are commonly grown. They differ mainly in the color, size, and shape of the seeds, and in the time needed for ripening. Some of the varieties are more hairy than others.
Soy beans may take many places in good crop-rotations, but they are unusually valuable in short rotations with small grains. The grains can be cut in time for the beans to follow them, and in turn the beans can be harvested in the early fall and make way for another grain crop.
It should always be remembered that soy beans will not thrive unless the land on which they are to grow is already supplied, or is supplied at the time of sowing, with bean bacteria.
[Ill.u.s.tration: FIG. 236. CHINESE SOY BEANS]
The plant will grow on many different kinds of soil, but it needs a richer soil than the cowpea does. As the crop can gather most of its own nitrogen, it generally requires only the addition of phosphoric acid and potash for its growth on poor land. When the first crop is seeded, apply to each acre four hundred pounds of a fertilizing mixture which contains about ten per cent of phosphoric acid, four per cent of potash, and from one to two per cent of nitrogen.
If the crop is planted for hay or for grazing, mellow the ground well, and then broadcast or drill in closely about one and a half bushels of seed to each acre. Cover from one to two inches deep, but never allow a crust to form over the seed, for the plant cannot break through a crust well. When the beans are planted for seeds, a half bushel of seed to the acre is usually sufficient. The plants should stand in the rows from four to six inches apart, and the rows should be from thirty to forty inches from one another. Never plant until the sun has thoroughly warmed the land. The bean may be sowed, however, earlier than cowpeas. A most convenient time is just after corn is planted. The rows should be cultivated often enough to keep out weeds and gra.s.s and to keep a good dust mulch, but the cultivation must be shallow.
[Ill.u.s.tration: FIG. 237. SOY BEANS]
As soy beans are grown for hay and also for seed, the harvesting will, as with the other legumes, be controlled by the purpose for which the crop was planted. In harvesting for a hay crop it is desirable to cut the beans after the pods are well formed but before they are fully grown. If the cutting is delayed until the pods are ripe, the fruit will shatter badly. There is a loss, too, in the food value of the stems if the cutting is late. The ordinary mowing-machine with a rake attached is generally the machine used for cutting the stalks. The leaves should be most carefully preserved, for they contain much nourishment for stock.
[Ill.u.s.tration: FIG. 238. SOY BEANS IN CORN]
Whenever the beans are grown for seeds, harvesting should begin when three fourths of the leaves have fallen and most of the pods are ripe.
Do not wait, however, until the pods are so dry that they have begun to split and drop their seeds. A slight amount of dampness on the plants aids the cutting. The threshing may be done with a flail, with pea-hullers, or with a grain-threshing machine.
The beans produce more seed to the acre than cowpeas do. Forty bushels is a high yield. The average yield is between twenty and thirty bushels.