Document Type



A study of the content and rate of decomposition of organic matter in soils is of considerable practical importance. The benefits derived from a supply of rapidly decaying organic matter in the soil include increased microbial activity, greater availability of nitrogen and other plant food constituents and the maintenance of good tilth in the soil and hence better crop yields. Under continuous cropping, as with corn, the rate of decomposition is fairly rapid and the content of organic matter drops to a low level unless regular additions are made. Under such a system some organic matter is added each year in the form of crop residues but the amount is not sufficient to balance the loss by decomposition. In general the amount of organic matter added in crop residues has been found to vary widely with the crop, the yields and any treatments which the soil may have received. It has been shown by numerous investigators (1, 2, 3, 4, 6, 7, 8) that the organic matter content of the soil bears a close relationship to the crop yields, that there is a greater loss of organic matter from the soil in intertilled crops, such as corn, than from those in noncultivated crops, such as wheat, and that it is not possible to maintain the organic matter content of the soil under continuous cropping unless heavy applications of manure are made.

Publication Date


Journal Title

Proceedings of the Iowa Academy of Science





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©1937 Iowa Academy of Science, Inc.



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