Part 3

When clover is seeded in an intertilled crop, such as corn, cotton, or tomatoes, the customary cultivation received by these crops is ordinarily sufficient preparation for crimson clover. In sandy soil the clover is often seeded without any immediate preparation, but a light stirring with a harrow-toothed cultivator is desirable if the ground is hard. If the clover is to be used for hay or seed, the preceding crop should be laid by level rather than in ridges. This will facilitate cutting the clover.

Where crimson clover is seeded after a crop of small grain, the stubble should be plowed or disked as soon as possible after the grain is cut. Stubble land dries out quickly, partly because the soil is suddenly left bare and partly because of the drain on the soil moisture by the crops of ragweed and other coarse-growing weeds which always follow a grain crop. Unless the soil is cultivated at once it becomes very difficult to obtain anything like an ideal seed bed for crimson clover. This difficulty is usually more pronounced after oats and barley than after rye and wheat. Ordinarily the best practice is to disk the grain stubble within a week after harvest and harrow every week, or at least after every rain, in order to settle the ground, destroy the weeds, and assist in holding the moisture pending the time of seeding the clover. Plowing the stubble is more expensive than disking and requires that the ground be allowed to settle for a month or six weeks in order to secure a firm seed bed. Plowing is an advantage in a wet season, because plowed ground dries readily; it is a disadvantage in a dry season for the same reason.

=FERTILIZERS.=

On moderately rich soil the fertilizer applied to the preceding crop is sufficient to produce a good crop of crimson clover. This is especially true where the clover follows such crops as potatoes or tomatoes, which ordinarily are heavily treated with fertilizers. It is important to realize, however, that crimson clover has a very short period of growth, and that to make a vigorous growth it must have a good supply of plant food. On sandy soils where fertilizers have not recently been applied it is often the practice to apply from 150 to 200 pounds of acid phosphate, with some potash fertilizer if it can be afforded. On clay soils 200 or 300 pounds per acre of acid phosphate ordinarily are sufficient. On many soils a light application of nitrate of soda will assist materially in giving the young clover plants a good start and often will enable them to withstand the effects of a late drought or severe winter which otherwise might have injured the stand. If the seeding has been delayed, as by waiting for suitable rains, an application of not more than 75 pounds of nitrate of soda per acre will stimulate the young plants and enable them to make a better growth before winter.

Fertilizer is usually applied at seeding time, but a few farmers have been found who apply it as a top-dressing very early the following summer, giving as a reason that there is then no loss from winter leaching and that by this method the plants are nourished at the time they are making their most vigorous growth. Such top-dressings of fertilizer should not be made while the leaves are wet with rain or dew. Where stable manure is applied to crimson clover very marked results follow. It may be spread just before seeding when the clover is not grown in an intertilled crop, or it may be applied as a top-dressing in winter or very early spring.

The more vigorous the growth that can be induced by the application of suitable fertilizers the more marked will be the increase in the yield of the succeeding crops. On soil in a low state of productivity the use of a reasonable amount of fertilizer will often enable a successful crop of clover and succeeding crops to be produced, where had not the fertilizers been applied the clover would have failed. Furthermore, the following crop, particularly if it be corn, would also fail to give the increased yield which follows a successful stand of crimson clover.

An application of barnyard manure will be found to be especially effective in obtaining a stand of crimson clover on any thin, galled spots in the field. The manure should be worked into the ground before seeding, and, if possible, a second application as a top-dressing should be given a day or two after planting. The top-dressing stimulates the seedlings and if strawy helps to protect them from the August sun.

=LIME.=

Crimson clover is not as dependent on lime as red clover and alfalfa, being more like alsike clover in this respect. It does not thrive on soils which are very "sour," but on well-drained soils in a productive condition crimson clover frequently makes a vigorous growth, even though the soil may show a high lime requirement. The stands are usually more uniformly good over the limed parts of such fields than on the unlimed parts, although it is sometimes questionable whether the benefit derived from liming is profitable. Liming is more often desirable on clay soils than on sandy soils, and usually gives better results when used in conjunction with fertilizers than when used alone. On light sandy soils deficient in humus burnt lime may be actually injurious. In considering the advisability of applying lime one must not lose sight of the need of lime on the part of such other crops as corn, cantaloupes, or peaches, which are either grown with or follow the clover. Inasmuch as the effect of liming varies greatly in different localities, it is suggested that small plats be treated experimentally at different rates before any considerable areas are limed.

=INOCULATION.=

A large part of the value of all clovers lies in their ability to utilize the nitrogen of the air and add it to the soil. When grown on rich land, the clovers, like many other plants, use the nitrogen already present in the soil and are not stimulated to contribute any to their own support or to the support of other crops. To enable the clover to use the nitrogen in the air the presence of the proper nodule-forming bacteria in the soil is necessary.

Fortunately, most of the soils in the crimson-clover sections appear to be already inoculated, and artificial inoculation is not often necessary, except on soils new to the crop. Crimson clover is inoculated by the same strain of bacteria which occurs on the roots of the other true clovers; consequently, a field which has produced a good stand of red, mammoth, alsike, white, hop, Carolina, rabbit's-foot, or buffalo clover is usually inoculated sufficiently for crimson clover. Sweet clover, Japan clover, and bur clover are not true clovers and are inoculated by a different strain of bacteria.

The importance of inoculation is well shown by an experiment conducted by the Alabama Agricultural Experiment Station. In this experiment yields of 4,057 and 6,100 pounds of crimson-clover hay were secured on inoculated soils, while on corresponding areas which were not inoculated the yields were 761 pounds on one area and nothing on the other.

The soil can be inoculated artificially by means of pure cultures of the bacteria or by the transfer of a small quantity of soil from another clover field. The latter method is the more certain, but is open to the danger of introducing noxious weeds, insects, and plant diseases, especially if the soil is brought from a distance. The presence of stem-rot in many sections makes the use of soil especially dangerous. This disease can, be carried with the soil from field to field.

Sufficient pure culture for inoculating seed for 1 acre can be secured free from the United States Department of Agriculture. Full directions for using the culture accompany each bottle. Directions for inoculating by the soil-transfer method can also be obtained from this Department.

=SEEDING.=

=TIME OF SEEDING.=

Crimson clover is usually sown between August 15 and October 1, the general rule being to plant about 60 days before the first killing frost is expected. South of Virginia crimson clover can be seeded as late as November 1, although if planted late more seed should be used and a light dressing of nitrate of soda applied, in order to stimulate the young plants. Seeding earlier than August 1 is seldom advisable unless the crop is sown with some other crop the shade of which will hold it back.

The exact date of planting depends almost entirely upon the moisture content of the soil. The principal condition to avoid is planting when the soil contains just enough moisture to germinate the seeds, but not enough to keep the plants growing. Usually it is better to plant when the soil is quite dry than when it is slightly moist, for in dry soil the seeds, if properly buried, lie without germinating and are ready to grow vigorously at the first rainfall. The most favorable time for seeding is just before or just after a good rain, when the soil is moist enough to form a ball in the hand.

=RATE OF SEEDING.=

The ordinary rate of seeding crimson clover is 15 pounds per acre, although the rate varies according to conditions. From 12 to 15 pounds per acre are usually sufficient when growing the crop for seed or when the soil is unusually rich. On poor soil, dry soil, or on soil which has not previously produced crimson clover 18 to 22 pounds of seed give better assurance of a stand. Heavy seeding is also desirable when planting late in the season or when a heavy crop is wanted for green manure early in the spring.

Theoretically, 2 pounds of seed per acre would provide six plants for every square foot, which is a satisfactory stand. Under ordinary circumstances, however, it is necessary to allow for some of the seed being too deep, or too shallow, or failing to germinate, and for a certain percentage of winterkilling. It is also well to have a fairly thick stand of the young plants, so that the ground may be well covered during the early fall and thus prevent soil washing and the growth of winter weeds.

=METHODS OF SEEDING.=

The most common method of seeding crimson clover in intertilled crops is to scatter the seed broadcast with a rotary seeder or by hand. (Fig. 6.) In order to place the seed on a fresh, moist seed bed it is commonly broadcasted immediately behind the cultivator at the last cultivation and is covered 'at once by a second cultivator. In tall corn the seed may be sown from horseback, the ears of the horse being covered with small bags to prevent the entrance of the flying seed. Slightly more seed is required when seeding in tall corn, as some seed catches in the corn plants. When seeding in cotton care must be taken to avoid injury to the opening bolls, which are easily knocked off or torn. This is best done by seeding by hand, covering the seed with a piece of brush dragged down the rows.

In low-growing truck crops and on fallow ground crimson clover can be seeded with a wheelbarrow seeder. This implement distributes the seed more evenly than can be done by hand or with the rotary seeder, especially when planting a mixture of crops. The wheelbarrow seeder being somewhat awkward to handle is better adapted to smooth, level fields than to hillsides.

Probably the very best method of seeding crimson clover is with the special clover or alfalfa drill. Where enough clover is grown to warrant its use this implement is to be highly recommended. The seed is sown in 4-inch rows at just the proper depth and with the right pressure, and the fertilizer is placed exactly under each row, where it will be immediately available to the seedlings. Drilled clover requires less seed than broadcasted clover and produces a more even and certain stand.

In place of the special clover drill an ordinary grain drill equipped with a clover-seed attachment can be used with good results. Special spouts should be arranged to lead from the clover-seed box back of the shoes or disks, in order to deposit the seed directly in the furrow. Chain furrow closers are best for covering the seed, as they leave the furrows broad and flat instead of =V= shaped and lessen the danger of the seedlings being covered with soil during a hard rain.

For use in intertilled crops there are several types of 1-row drills, the best for this purpose being the 5-hoe drill equipped with press wheels.