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Show ' Checking Evaporation. At the Wyoming station expert' ments were made to determine to what extent the stirring of the soil prevents the evaporation of water. To have all conditions under control twenty-flve-inch cylinders were used, and the water table was kept within twenty-two Inches of the surface of the soil. The soil in' the various cylinders cyl-inders was then stirred once a week, In one to the depth of two Inches, in another to the depth of four inches, and in a third to the depth of six inches. .The first retarded the evaporation evapo-ration to the amount of 19 per cent; the second retarded It 23 per cent, and the third 45 per cent. This shows the tremendous value of cultivation in a dry year, when 45 per cent increase in-crease in the water supply of plants might well make the whole difference between the loss and saving of an entire harvest. It Is somewhat surprising sur-prising to learn that the six-inch depth is so much more effective than the two-inch depth. Doubtless this arises from the shorter time required for the two-Inch mulch to settle back into a condition where capillary operation oper-ation is possible. This would differ much with different soils. The natural nat-ural conclusion is, however, that a two-inch stirring twice a week would be about as valuable as a six-Inch stirring once a week. Legumes. Bulletin 45, Arizona: The legumes j constitute a group of plants of so great Importance to the farmer, and information concerning .them r is .. so much in demand, that a brief statement state-ment as. to. which ones may.be grown in southern Arizona is deemed advisable. advisa-ble. The great Importance of the legumes is Jue largely to their ability to obtain the nitrogen they need from the .air -mixed -with the .soil In which they- are situated. This they . do through the agency of minute organ-Isms, organ-Isms, called bacteria, growing In large colonies upon their roots, and by irritation ir-ritation producing there the nodules or wart-like bodies so characteristic of them.; The group is a very .large one,, and members of.it are. found in nearly all parts, of the earth. Among the ones best known- to us are peas, beans, clovers, alfalfa, vetches, lupins, locust trees, mesquite, acacia, - palo verde, ironwood, and the "ground nutome . jtts'nf the world, especially the temperate and warm regions, re-gions, these plants constitute a considerable con-siderable part of ' the native vegetation, vegeta-tion, and have for ages been adding to the nitrogen of the soil by growing ' and decaying in it. In some regions the . legumes are principally annuals, in others, perennial herbs, and in still others, shrubs or trees. Subsoiling. Bulletin 66, Arkansas Experiment station: .Subsoiling like other farm operations may be rightly or wrongly done. Certain crops derive greater benefits from it than others, and the same is true of certain soils. Stiff soils, those with a close or tenacious subsoil and soils under .which'' has formed a hardpan, are undoubtedly -benefited by subsoiling, while . the operation op-eration has a drying effect upon soils inclined to be too wet, and increases the capacity of soils for holding moisture mois-ture in periods of drouth. It enables the roots of plants to penetrate more freely and deeper in search of plant food and moisture, it increases the bulk of the soil proper, and permits of freer circulation of air in the soil. A loose, sandy soil that Is naturally quite deep will not in all probability derive much -benefit from subsoiling unless the operation is accomplished by the incorporation of a quantity of organic matter. Very nearly all subsoils, sub-soils, as they naturally exist, are unproductive, un-productive, and if brought to the surface sur-face In quantity the result at first will probably be to decrease rather than increase the yield. A Fertile Soil is Drouth Resistant. Keep the soil rich if you wish it to be able to carry its crops through the drouth. The farms in the east that have been robbed of their fertility have also become the prey of drouth. The sparse crops on them fall down easily , under the glare of the hot sun from a rainless sky. This is the observation ob-servation of good farmers; It is also the .teachings of science. Among the many experiments that bear out the above statements is a recent one imported im-ported from Germany. Rye, wheat, barley, peas, beans, potatoes and field beets were given varying quantities of a complete fertilizer application, and the number of fibrous roots to a depth of about five feet were ascertained. The results indicated that in general a good supply of plant food tends to produce a strong, well-developed root system, with roots growing to greater depths than when the supply of plant food is limited. For this reason the heavily fertilized crops are better able to withstand drouth than those having received but light applications. ! |