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ing clover, since in these soils the lack is more one of humus than of plant food. The application of farmyard manure will answer the same purpose, if it can be spared for such a use.

Other soils are so acid that clovers will not grow on them until the acidity is corrected, notwithstanding that plant food may be present in sufficient quantities. Such are soils, in some instances at least, that have been newly drained, also soils that grow such plants as sorrels. This condition will be improved if not entirely corrected by the application of lime. On such soils this is most cheaply applied in the air-slaked form, such as is used in plastering and in quantities to effect the end sought. These will vary, and can only be ascertained positively by experiment.

Usually it is not necessary to apply much farmyard manure in order to induce growth in nearly all varieties of clover, and after free growth is obtained, it is not usually necessary to supply any subsequently for the specific purpose named. In some soils, however, alfalfa is an exception. It may be necessary to enrich these with a liberal dressing of farmyard manure to insure a sufficiently strong growth in the plants when they are young. Having passed the first winter, further dressings are not absolutely essential, though they may prove helpful.

Farmyard manure applied on the surface will always stimulate the growth of clovers, but it is not common to apply manure thus, as the need for it is greater in growing the other crops of the farm. When thus applied, it should be in a form somewhat

reduced, otherwise the coarse parts may rake up in the hay. It is better applied in the autumn or early winter than in the spring, as then more of the plant food in it has reached the roots of the clover plants, and they have also received benefit from the protection which it has furnished them in winter.

In a great majority of instances, soils are sufficiently well supplied with the more essential elements of fertility to grow reasonably good crops of clover, hence it has not usually been found necessary to apply commercial fertilizers to stimulate growth, as in the growing of grasses. In some instances, however, these are not sufficiently available, especially is this true of potash. Gypsum or land plaster has been often used to correct this condition, and frequently with excellent results. It also aids in fixing volatile and escaping carbonates of ammonia, and conveys them to the roots of the clover plants. It is applied in the ground form by sowing it over the land, and more commonly just when the clover is beginning to grow. The application of 50 to 200 pounds per acre has in many instances greatly increased the growth, whether as pasture, hay or seed. The following indications almost certainly point to the need of dressings of land plaster: 1. When the plants assume a bluish-green tint, rather than a peagreen, while they are growing. 2. When the plants fail to yield as they once did. 3. When young plants die after they have begun to grow in the presence of sufficient moisture. 4. When good crops can only be grown at long intervals, as, say, 5 to 8 years. It has also been noticed that on some soils where

gypsum has long been used in growing clover the response to applications of the plaster is a waning one, due doubtless to the too rapid depletion of the potash in the soil.

Potassic fertilizers give the best results when applied to clovers, but dressings of phosphoric acid may also be helpful. Applications of muriate or sulphate of potash or kainit may prove profitable, but on many soils they are not necessary in growing clover. Wood ashes are also excellent. They furnish potash finely divided and soluble, especially when applied in the unleached form. When applied unleached at the rate of 50 bushels per acre and leached at the rate of 200 bushels, the results are usually very marked in stimulating growth in clover.

Seasons for Sowing.-Clovers are more commonly sown in the springtime in the Northern States and Canada than at any other season and they are usually sown early in the spring, rather than late. On land producing a winter crop, as rye or wheat, they can be sown in a majority of instances as soon as the snow has melted. That condition of soil known as honeycombed furnishes a peculiarly opportune time for sowing these seeds, as it provides a covering for them while the land is moist, and thus puts them in a position to germinate as soon as growth begins. Such a condition, caused by alternate freezing and thawing, does not occur on sandy soils. Where it does not so occur, sowing ought to be deferred until the surface of the ground has become dry enough to admit of covering with a harrow. As in sowing the seeds of certain grasses good

results usually follow sowing just after a light fall of snow, which, as it melts, carries the seed down into the little openings in the soil. But there are areas, especially in the American and Canadian northwest, where in some seasons the young clover plants would be injured from sowing the seed quite early. This, however, does not occur very frequently. When sown on spring crops, as spring wheat, barley and oats, the seed cannot, of course, be sown until these crops are sown. The earlier that these crops are sown the more likely are the clovers sown to make a stand, as they have more time to become rooted before the dry weather of summer begins. In a moist season the seed could be safely sown any time from spring until mid-summer, but since the weather cannot be forecast, it is considered more or less hazardous to sow clovers in these northern areas at any other season than that of early spring. If sown later, the seed will more certainly make a stand without a nurse crop, since it will get more moisture. If sown later than August, the young plants are much more liable to perish in the winter.

In the States which lie between parallels 40° and 35° north, and between the Atlantic and the 100th meridian west, clover seeds may be sown in one form or another from early spring until the early autumn without incurring much hazard from winter killing in the young plants, but here also early spring sowing will prove the most satisfactory. The hazard from sowing in the summer comes chiefly from want of sufficient moisture to germinate the seed.

In the Southern States the seed is sown in the early spring or in the autumn. If sown late, the heat of summer is much against the plants. Seeds sown in the early autumn as soon as the rains come will make a good stand before the winter, but there are some soils in the South in which alternate freezing and thawing in winter, much more frequent than in the North, would injure and in some instances destroy the plants.

In the Western valleys where irrigation is practiced, clover seeds may be sown at any time that may be desired, from the early spring until the early autumn. The ability to apply water when it is needed insures proper germination in the seed and vigor in the young plants.

Methods of Sowing.-Clover seed may be sown by hand, by hand machines, and by the grain drill, with or without a grass-seed sowing attachment. Thèse respective methods of sowing will be discussed briefly here, but since they are practically the same as the methods to be followed in sowing grass seeds, and since they are discussed more fully in the book "Grasses and How to Grow Them" by the author, readers who wish to pursue the subject further are referred to the book just named.

When clovers are sown by hand, usually but one hand is used. Enough seed is lifted between the thumb and two forefingers of the right hand to suffice for scattering by one swing of the same. On the return trip across the field the seed should be made to overlap somewhat the seed sown when going in the opposite direction. In other words, the seed

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