SWEET Clover in Dry-Farming Belt, Once Started, Rarely Fails

Sweet, clover, either alone or in combination with grasses, is rapidly increasing in popularity in the Great Plains States. Wherever the annual rainfall is 15 inches or more, sweet clover can be grown successfully with at least, as much regularity as wheat. Like all cultivated crops under dry farming, sweet clover is subject to failures of the seeding, but when the crop is once started it rarely fails thereafter. Unlike other legumes, sweet clover is not often injured by drought, grasshoppers, rabbits, or even sand and hail storms, and it does not usually cause bloat when pastured. Because of its hardiness, sweet clover will probably become the standard leguminous pasture crop of the semiarid region.

Recent experiments have indicated several practices that increase the chances of obtaining a stand of sweet clover. Chief among these are early planting and a firm seed bed. The most reliable time for seeding is late winter. Beginning in northern Texas about January 15, the most favorable planting date recedes northward until it becomes March 15 at the Canadian boundary. Each week that planting is delayed after the most favorable date greatly lessens the chances of obtaining a stand and markedly reduces the size of the plants.

Sweet clover is even more sensitive to a loose, dry seed bed under dry farming than under humid farming. A hard, compact seed bed is absolutely essential. The most consistent success with sweet clover has been had from drilling unhulled or unscarified seed on sorghum, corn, or Sudan-grass stubble. Complete failure usually follows seeding on freshly plowed land. Planting later than April 15 on loose soil is simply inviting disaster.

While not so imperative as date of planting, the method of planting is also important. Drilled stands are nearly always better than seedings broadcast by hand, especially if a press drill or some means of firming the soil around the seed is used. However, hand sowing on frozen ground in February is better than machine sowing in April or May.

The use or nonuse of a nurse crop depends chiefly on the weediness of the land. Upon soil that is reasonably free of weed seeds, as good clean sorghum stubble, sweet clover may be seeded alone, and, in favorable years, a good crop of hay harvested in the fall.  If it is felt that a grain crop is necessary, a half seeding of wheat or barley will not injure the stand of clover, but the clover plants will not be large enough to cut for hay in the fall except in exceptional years. A full seeding of grain eliminates the hay crop and may in dry years destroy the sweet-clover stand.

On weedy land there is nothing to do but use a nurse crop. In dry years there will then be a poor crop of grain, a fair crop of weeds, and no clover. In wet years there will be a good crop of grain and of weeds and a fair crop of clover. Without the grain for a nurse crop, the weeds will outgrow the clover in both dry and wet years.  The best type of nurse crop varies in different localities, but in general is in the descending order of winter wheat, flax, spring wheat, barley, and oats.

Much interest is expressed in the possibility of getting sweet clover established in native sod. The chances are against this, principally because the sweet-clover seed can not easily get down through the sod into the soil. Some success has been had by drilling the seed into the sod during a thaw in February or March. Others have obtained stands of sweet clover through sod land by plowing shallow furrows 3 feet apart across the field and sowing sweet clover in the fresh earth thus turned. Still others sow the unhulled seed in the sod in late fall and have it tramped into the soil with sheep during the winter and early spring.

A better way to obtain the full value from sweet clover is to rotate it with Sudan grass. The Sudan grass provides excellent grazing during the 6-weeks’ gap that is likely to occur in midsummer between the time when the old sweet clover is finished and the new seeding of sweet clover is large enough for pasturing. The Sudan-grass stubble then provides an excellent seed bed for the next sweet-clover seeding.