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some instances be added to timothy in the mixtures. Some other grasses may also be added under certain conditions, or substituted for timothy or redtop. In certain instances, it has also been found profitable to mix certain of the clovers in addition to adding grass seeds when hay is wanted. The more important of these mixtures will be referred to when treating of growing the different varieties in subsequent chapters. When growing them, the aim should be to sow those varieties together which mature about the same time. The advantages from growing them together for hay include larger yields, a finer quality of hay, and a more palatable fodder.

In the past it has been the almost uniform practice to sow alfalfa alone, but this practice is becoming modified to some extent, and is likely to become more so in the future, especially when grown for pasture.

When sown to produce pasture, unless for one or two seasons, clover seed is sown in various mixtures of grasses in all or nearly all instances. The grasses add to the permanency of the pastures, while the clovers usually furnish abundant grazing more quickly than the grasses. Several of them, however, are more short-lived than grasses usually are, hence the latter are relied upon to furnish grazing after the clovers have begun to fail. In laying down permanent pastures, the seed of several varieties is usually sown, but in moderate quantities. The larger the number of the varieties sown that are adapted to the conditions, the more varied, the more pro

longed and the more ample is the grazing likely to be.

When clovers, except the crimson variety, are sown for the exclusive purpose of adding to the fertility of the land, they are usually sown along with some other crop that is to be harvested, the clover being plowed under the following autumn or the next spring. These are usually sown without being mixed with other varieties, and the two kinds most frequently sown primarily to enrich the land are the medium red and crimson varieties. The former grows more quickly than other varieties, and the latter, usually sown alone, comes after some crop already harvested, and is buried in time to sow some other crop on the same land the following spring.

Sowing with or without a Nurse Nurse Crop. -Nearly all varieties of clover are usually sown with a nurse crop; that is, a crop which provides shade for the plants when they are young and delicate. But the object in sowing with a nurse crop is not so much to secure protection to the young plants as to get them established in the soil, so that they will produce a full crop the following season. Two varieties, however, are more commonly sown alone. These are alfalfa and crimson clover.

Alfalfa is more commonly sown alone because the young plants are somewhat delicate and easily crowded out by other plants amid which they are growing. Because of the several years during which alfalfa will produce crops when once established, it is deemed proper to sacrifice a nurse crop in order to get a good stand of the young plants. The other

clovers are usually able to make a sufficient stand, though grown along with a nurse crop. In some situations alfalfa will also do similarly, as, for instance, where the conditions are very favorable to its growth. Crimson clover is more commonly sown alone for the reason, first, that it is frequently sown at a season when other crops are not being sown; second, that it grows better without a nurse crop; and third, that if grown with a nurse crop the latter would have to be used in the same way as the clover.

Some have advocated sowing clovers without a nurse crop under any conditions. Such advocacy in the judgment of the author is not wise. It is true that in some instances a stand of the various clovers is more certainly assured when they are sown without a nurse crop, but in such situations it is at least questionable if it would not be better to sow some other crop as a substitute for clover. But there may be instances, as where clover will make a good crop of hay the year that it is sown, when sowing it thus would be justifiable. In a majority of instances, however, it will not make such a crop, because of the presence of weeds, which, in the first place, would hinder growth, and in the second, would injure the quality of the hay.

The nurse crops with which clovers may be sown are the small cereal grains, as rye, barley, wheat and oats. Sometimes they are sown with flax, rape and millet. They usually succeed best when sown along with rye and barley, since these shade them less and are cut earlier, thus making less draft on moisture

in the soil and admitting sunlight at an earlier period. Oats make the least advantageous nurse crop, because of the denseness of the shade, but if they are sown thinly and cut for hay soon after they come into head, they are then a very suitable nurse crop. One chief objection to flax as a nurse crop is that it is commonly sown late. The chief virtue in rape as a nurse crop is that the shade is removed early through pasturing. The millets are objectionable as nurse crops through the denseness of the shade which they furnish and also because of the heavy draught which they make on soil moisture. Peas and vetches should not be used as nurse crops, since they smother the young clover plants through lodging in the advanced stages of their growth.

Amounts of Seed to Sow.-The amounts of clover seed to sow are influenced by the object sought in sowing; by combinations with which the seeds are sown, and by the relative size of the seeds. The soil and climate should also be considered, although these influences are probably less important than those first named.

When clovers are sown for pasture only, or to fertilize the soil speedily and to supply it with humus, the largest amounts of seed are sown. But for these purposes it is seldom necessary to use more than 12 pounds of seed per acre. These amounts refer to the medium red and mammoth varieties, which are more frequently used than the other varieties for the purposes named. They also include the crimson sown usually to fertilize the soil. When

sown to provide seed only, 12 pounds per acre of the

medium red, mammoth and crimson varieties will usually suffice. Half the quantity of alsike will be enough, and one-third the quantity of the small white, or a little more than that. Whether alfalfa is grown for seed, for hay or for pasture, about the same amounts of seed are used; that is, 15 to 20 pounds per acre. When sown with nurse crops and simply to improve the soil, it is customary to sow small rather than large quantities of seed, and for the reason that the hazard of failure to secure a stand every season is too considerable to justify the outlay. From 4 to 5 pounds per acre are frequently sown and of the medium or mammoth variety.

When the mammoth and medium varieties of clover are sown for hay with one or two kinds of grass only, it is not common to sow more than 6 to 8 pounds of either per acre. The maximum amount of the seed of the alsike required when thus sown with grasses may be set down at 5 pounds per acre. These three varieties are chiefly used for such mixtures. With more varieties of grass in the mixtures, the quantities of clover seed used will decrease. When clovers are sown with mixtures intended for permanent pastures, it would not be possible to name the amounts of seed to sow without knowing the grasses used also, but it may be said that, as a rule, in those mixtures, the clovers combined seldom form more than one-third of the seed used.

The seeds of some varieties of clover are less than one-third of the size of other varieties. This, there'fore, affects proportionately, or at least approxi

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