Nitrogen and organic matter in dry-farm soils
1914
Stewart, R. | Hirst, C.T.
The dry-farm soils of Utah are remarkably well supplied with calcium carbonate, thus rendering the addition of this substance unnecessary even in the very remote future. The results of the study reported herein, together with those previously reported, do not show any such marked decrease in the nitrogen and humus supply of the surface cultivated dry-farm soils, as has been found by previous investigators. This is probably due to the deep-rooted character of the wheat plant when grown under dry-farm conditions and to the fact that very little erosion takes place by wind or water. In the virgin condition our dry farm soils are very low in nitrogen. The character of the native vegetation is such as to add little organic matter to the soil during the virgin state. The deep-rooted wheat plant secures a portion of its nitrogen from the lower depths of the soil. The plowing under of the straw and stubble tends to maintain the nitrogen content of the surface cultivated soil. The dry-farm soils of Utah are well supplied with limestone and the mineral elements of plant food, thus making the maintaining of the nitrogen supply the most important part of the soil fertility problem of the dry farm in Utah. It is therefore imperative that the farmer use every means at his command to plow under the straw and stubble. The future may demonstrate the necessity of utilization of a leguminous crop for this purpose.
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