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Show PROBLEMS FOP, DRY FARMERS Knowledge of Erects of Nitrogen and Humus Content of Soil Is of Vital Importance. (BY DR. ROBERT STEWART.) A knowledge of the effect of dry land farming upon the nitrogen and humus content of the soil is necessary neces-sary before, a permanent system of dry land farming can be established. Almost coincident with the development develop-ment of scientific dry land farming, the determental effects of such a system sys-tem on the nitrogen and humus content con-tent of the Cu!.ivutfcS. soli etegpsted itself to the careful student of the subject. The history of scientific agriculture agri-culture taught that the cropping of land to the same crop caused a decrease de-crease in the nitrogen and humus content con-tent of the cultivated soil. It also taught that summer-fallowing was even more destructive to those im: portant constituents than was continuous contin-uous cropping itself. The importance of nitrogen In crop production and the preponderance of evidence regarding the destruction of organic matter and the resulting loss of nitrogen by practicing a system of crop production Involving the use of the summer-fallow, have caused thoughtful students of the subject to suggest means of returning the organic or-ganic matter and the nitrogen to the soil. For this purpose, the growing of legumes during the season when the land is not occupied by the wheat have been suggested, but this practice defeats the purpose of the summer-fallow, summer-fallow, inasmuch as the limited supply sup-ply of moisture is called upon to grow the legume. In view of the known action of continuous con-tinuous cropping and summer-fallowing upon the nitrogen and humus of humid soils, a knowledge of the effect of dry farming upon the nitrogen and humus of dry-land soils became of exceedingly ex-ceedingly great Importance. With this idea in view the author, In the summer of 1907, had a survey made of the dry-farming area in Cache valley, val-ley, the oldest dry-farming district in the state of Utah, and the conclusions reached were as follows: 1. The cropping of dry-farming land in Cache valley to wheat, either by the summer-fallowing method or by continuous cropping, does not decrease de-crease the nitrogen or humus of the surface foot of soil. 2. The second foot of grain-cropped land contains less nitrogen and humus hu-mus than does the second foot of the adjacent virgin soil. 3. The observed phenomenon in case of the grain-cropped land is probably due to the addition of nitrogen nitro-gen to the surface foot from lower depth and the addition f the humus from the added straw. 4. The work indicated that in a study of the nitrogen and humus problem In dry-land farlng attention must be paid to greater depth of soil than the traditional plowed surface. |