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being ascertained that it will grow on a great variety of soils, providing they are reasonably fertile, free from acidity, sufficiently porous below to carry away water with reasonable quickness, and not underlaid with hard pan or a subsoil so tenacious that it is almost impervious to water.

The best soils for alfalfa are those of the Western mountain States, and in these the deposit soils of the river valleys stand among the foremost. These soils are usually of much depth. Many of them have water underneath, and the subsoil is usually so porous that the roots can go far down in them, such is the character of nearly all the bottom land west of the Mississippi. But in nearly all of the mountain region of the West, from Banff in British Columbia to Mexico, alfalfa will grow well under irrigation, or in the absence of irrigation, if ground water is not too distant from the surface. In this region alfalfa grows more vigorously and more persistently than in almost any other portion of the United States.

In regions where alfalfa is not dependent upon irrigation, the best soils probably are deep, rich calcareous loams, clay or sandy, and underlaid with what may be termed a mild or reasonablý porous clay subsoil. With such soils the plants may be in no way influenced by sheet water below, as on some of these in Nebraska, for instance, such water is fully 150 feet below the surface. These soils are usually possessed of abundant food supplies to nourish the plants, and the roots can go far down into the subsoils to gather food and moisture. Such

lands are found more or less in nearly all the States of the Union east from the Rocky Mountains; hence, when the requisite bacteria are present, good crops can be grown on them in every State in the Union.

On the ordinary black soils of the prairie, alfalfa will usually grow reasonably well if underlaid with clay not too distant nor too tenacious. When the roots get down into the subsoil, they can usually find much food in the same, and unless in very dry areas a sufficiency of moisture, but in many instances it may be necessary to introduce the requisite bacteria, and to apply farmyard manure to encourage sufficient growth to carry the roots down quickly to the subsoil. In some prairie soils the growth will be vigorous from the start, but usually these are lands that have grown hardwood timber, and that have in them more or less clay.

In climates where the rainfall is considerable, alfalfa will frequently grow well on gravelly soils and on those that are stony. Some of the best alfalfa soils in the State of New York, New England States, and in the Canadian provinces of Quebec and Ontario are of this character.

Alfalfa will frequently grow fairly well even on stiff clays, and in some instances on gumbo soils. But these soils must not be so retentive as to collect and hold water for any considerable time within a few feet of the surface. Such lands have usually much staying power; hence, alfalfa grown on them frequently improves for years after it has been sown. On the reddish soils that cover much of the South, it has been found, as in growing alfalfa on stiff

clays in the North, that where deep subsoiling is practiced alfalfa is not only more easily established, but it also grows with added vigor.

On upland soils sandy or gravelly in character where the rainfall is much less than normal and where the subsoil is not underlaid with sheet water, alfalfa will not usually succeed, notwithstanding that it may grow well on these soils where the rainfall is normal. On such soils it is not easy to get a stand of the plants, as they are much apt to perish in the dry weather of the first season, but if once established on such soils the plants have much power to grow even where the rainfall is considerably less than normal.

Alfalfa will not grow well in soils naturally wet until they are drained. And when drained it will not grow with normal vigor, on what may be termed slough soils, where the subsoil is far down and covered with a deep covering of vegetable mold. What are termed slough soils in the Western prairies, therefore, are not well fitted for the growth of alfalfa. On these it may not succeed well, when it may grow with much vigor on the adjoining upland. When some wet soils are drained. alfalfa may not succeed well on them for a time and later may grow luxuriantly. This may arise from the lack of time for proper aeration after being drained, or from the want of lime to further correct acidity in the soil, or from the want of the proper bacteria. Notwithstanding that alfalfa will not grow well on undrained lands that are naturally wet, and notwithstanding that it will perish if the roots reach standing water at a dis

tance too near the surface, the best crops by far are usually grown on irrigated lands. This arises, first, from the ability to adjust the supplies of water to meet the needs of the plants, and second, from the congenial character of the soil and subsoil. Next to these the best crops are grown where congenial soils are underlaid with ground water, not too near nor too distant from the surface. On these soils the plants are largely supplied with moisture from the water below ascending on the principle of capillary attraction. How near or how distant such water should be will depend somewhat on subsoil conditions. It would seem correct to say that it ought never to come nearer to the surface than 3 feet, nor should it be more than 20 feet down. The most suitable distance would be, say, 8 to 16 feet. When the roots of alfalfa reach water at too short a depth they will die.

Alfalfa may sometimes be grown satisfactorily on soils subject to overflow, but usually there is hazard in growing it on these. If the overflow occurs comparatively early in the season, if it is not of great depth, if it is of short duration, and if the waters quickly drain out of the subsoil possessed by the alfalfa, it may receive little or no harm from such overflow. Instances are on record wherein ice has formed on alfalfa and yet the plants survived, but such a condition will usually prove fatal to them. But should the overflow take place in hot weather, usually it will injure the plants seriously, and may, indeed, completely destroy them. So great is such hazard, that care must be taken against the applica

tion of an excess of irrigating waters under such conditions. Overflow waters that are stagnant are more injurious probably than those that are in motion, owing, it may be, to the less supply of dissolved oxygen in the former.

Soils suitable in themselves, but lying on stiff clay bottoms or underlaid with hard pan within two or three feet of the surface, will not maintain a good stand of alfalfa. The plants in these may grow well for a time, probably a year or two, after which they will fail. The roots are not able to go down to gather food. When the subsoils are simply stiff clays, deep subsoiling, as already intimated, may render much service, but when composed of hard pan this may not be practicable. In moist climates, however, reasonably good crops have been obtained from soils with underlying rock not more than four feet below the surface.

The fact should not be overlooked that soils may have the requisite physical conditions for growing alfalfa, and they may possess in fair supply the essential elements of plant food, and yet alfalfa will not succeed at the first when sown on these, because of the absence of the soil bacteria, the presence of which is essential to the vigorous growth of the plants. Because of this, growers should be slow to conclude that alfalfa will not flourish on the soils on which they sow it until they have first tried to grow it on those soils that have been inoculated with the requisite alfalfa bacteria. For the methods of procedure in such cases see page 53. Some persons claim that soils which will grow medium red clover

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