Part 2

The use of unhulled seed offers the distinct advantage of increasing the chance of obtaining thick stands. With the prevalence of dry soil conditions, light rainfall does not cause the unhulled seed to germinate, but hulled seed germinates readily and the seedlings may die from lack of moisture before they can become established.

Its bulky nature makes unhulled seed more difficult to distribute uniformly than hulled seed. It must be broadcast and may be harrowed in. It is also difficult to market and is not generally handled by the seed trade. But farmers can harvest seed for their own use and save the expense of having it hulled.

=Companion Crops=

Rye, vetch, Italian ryegrass, and fall-sown grain crops are often seeded with crimson clover. Besides making a valuable addition to the clover (fig. 4), these companion crops help bolster up a thin stand. Such crops are seeded from one-half to one-third the normal crop rate and the crimson clover is seeded at the normal rate. Planting is done at the same time, but, as a greater depth is required for most of the seed of the companion crops, two seeding operations are necessary. In Tennessee, farmers often use a mixture of 5 pounds of red clover and 10 pounds of crimson clover per acre with excellent results. The first growth of the mixture may be grazed or harvested for hay or for crimson clover seed, while the second crop is wholly red clover.

=Diseases and Insects=

The only serious disease that affects crimson clover is stem rot. The effect of this disease is seen in the early spring and is characterized by the plants dying in patches. The stems rot at the surface of the soil or where they join the crown. The occurrence of continued damp cool weather during early spring favors the development of the disease. Exclusion of clover and other legumes from the rotation for a period of 2 to 5 years is the best control method.

Sandy soils in the southern part of the crimson clover belt are often infested with nematodes. Nematode injury results in a stunting and yellowing of the plants and is most prevalent in the southern part of the region. While the clover-seed chalcid, the pea aphid, and other insects sometimes become numerous in crimson clover, insects do not ordinarily cause appreciable damage.

=Utilization=

Crimson clover grows rapidly in early spring and furnishes an abundance of early grazing (fig. 5). If planted early and an abundant fall growth is made, the clover may also be grazed during the fall and winter months. Such a practice has been successfully followed in Tennessee, where crimson clover has provided the winter pasturage. The grazing, however, should be restricted to periods when the soil is relatively dry, otherwise damage may result from trampling. Animals grazing on crimson clover seldom bloat; however, it is advisable not to turn them into clover fields for the first time when they are hungry. Bloat is less likely to occur when a mixture of clover and grass or grain is grazed than when the clover alone is grazed. As crimson clover reaches maturity the hairs of the heads and stems become hard and tough. When grazed continuously or when fed as hay at this stage of maturity large masses of the hairs are liable to form into hair balls in stomachs of horses and mules. Occasionally the hair balls are responsible for the death of animals. If small amounts of other feeds, particularly roughages, are fed along with the clover, the formation of these balls will be reduced. Cattle, sheep, and swine do not seem to be affected.

Crimson clover makes excellent hay when cut at the early bloom stage although the yield may be slightly reduced. For maximum yields it should be harvested in full bloom. The hay is easily cured either in the swath or in the windrow. Fewer leaves are lost and less bleaching occurs in windrowed hay. Although yields as high as 2½ tons per acre are not uncommon on fertile soil, 1½ to 2 tons is an ordinary production.

Crimson clover is an ideal green-manure crop. For the best result it should be plowed under 2 to 3 weeks before planting the succeeding crop. This gives sufficient time for decomposition, which is rapid unless the crop is mature when plowed under. Occasionally, strips are plowed in which row crops are planted, allowing the clover between the plowed strips to mature. Seed may be harvested by hand from the clover between the row crop, and the remaining clover straw allowed to mat and serve as a mulch, or the entire plant may be permitted to form a mulch. A volunteer seeding may be secured in this way, especially in the northern part of this region, but attempts to follow such a practice should be tried on a small scale until experience is gained. When used in orchards, crimson clover is often allowed to mature, after which it is disked into the soil. Occasionally a volunteer seeding may be obtained in the fall.

=Seed Production=

Crimson clover is a prolific seed-producing plant and yields of 5 to 10 bushels per acre are common, depending upon the thickness of the stand, the amount of growth that is produced, and the care exercised in harvesting the seed. The florets are self-fertile, but bees are effective in tripping and transferring the pollen, with a consequent increase in the number of seed per head. The placing of colonies of honeybees adjacent to blooming fields will effectively increase pollination. More seed is usually produced on soils of medium fertility than on rich soils, since fertile soils seem to stimulate the growth of stems and leaves at the expense of flower-head development.

Large yields and ease of harvesting crimson clover seed are the principal reasons why crimson clover is such an ideal legume crop. Farmers may save seed with very little expense other than their own labor. When the seed heads are mature they readily shatter and are easily harvested either by hand stripping or by using horse-drawn homemade strippers. One bushel of unhulled seed contains about 2 pounds of hulled seed, and although bulky in nature, it can be easily stored on the farm until fall.

When the seed is mature the crop is cut with a mower, which may be equipped with a bunching or windrowing attachment (fig. 6) or it may be harvested with a combine. During wet seasons difficulties in combining the seed from standing plants may be experienced. Under such conditions the plants may be cut and windrowed and then threshed by the combine from the windrow. As crimson clover shatters easily when ripe, cutting with the mower when the heads are damp with dew or rain is recommended. If allowed to stand too long after it is ripe a beating rain will shatter much of the seed. After a few days of curing, the seed is hulled with an ordinary clover huller or a grain separator equipped with hulling attachments. The less the clover is handled, the less seed will be lost by shattering.

Troublesome weeds are encountered in growing crimson clover seed; field peppergrass (Lepidium campestre) and wintercress (Barbarea praecox) are probably the worst, as their separation from the clover seed is difficult. Little barley (Hordeum pusillum) is objectionable in unhulled seed, and the use of unhulled seed will naturally increase the prevalence of this weed.

U. S. GOVERNMENT PRINTING OFFICE: 1938

For sale by the Superintendent of Documents, Washington, D. C. -- Price 5 cents

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=Transcriber Note=

Illustrations moved to avoid splitting paragraphs and closer to references in the text. Minor typos may have been corrected.