The relation between effective rainfall and total calcium and phosphorus in alfalfa and prairie hay
1935
Daniel, H.A. | Harper, H.J.
Thirty samples of little blue stem (Andropogon scoparius) were collected each season for 5 years from Kirkland loam soil. Twenty of these samples were taken from plats that were fertilized each year with commercial fertilizer and 10 of the samples were obtained from unfertilized areas. Sixty-eight samples of alfalfa hay were collected from a brown sandy loam, similar to the Bates series of soils, at each cutting for 2 years. Forty-eight samples were taken from plats that were fertilized with commercial fertilizer and farm manure, and 20 samples were obtained from unfertilized soil. The native grass and alfalfa samples were analyzed for total calcium and phosphorus, and these elements were correlated with the effective seasonal rainfall. During periods when rainfall was high the calcium content of the plants decreased and the phosphorus content increased. When the effective rainfall was low, the calcium content of the plants increased and the phosphorus content decreased. A knowledge of differences which occur in plant composition is important since mineral deficiencies may or may not be present in forage produced on the same soil during different seasons.
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