Effects of soil type and soil treatments on the chemical composition of alfalfa plants

This paper reports experimental data obtained from a partial chemical analysis of alfalfa grown on Isabella sandy loam, Montcalm sandy loam, Mancelona gravelly sandy loam, Fox sandy loam, Brookston loam, Brookston clay loam, Brookston silt loam, Gilford loam, and Miami silt loam. The first cuttings of alfalfa grown on the several soil types exhibited a much lower ratio of leaves to stems than the second cuttings at the one-half bloom stage. Also, the weight of stems exceeded that of the leaves in the first cuttings, which was just the opposite of the condition for the second cutting. In both the stems and leaves the nitrogen content tended to be higher in the second than in the first cuttings of alfalfa harvested in the one-half bloom stage. Regardless of soil type and soil treatment the calcium content of alfalfa leaves was from two to three times greater than that of the stems. In case of plants grown on Isabella sandy loam soil the calcium content of the stems tended to be higher in the second than in the first cuttings, but the opposite was true in the case of the leaves. In the other soil types, the data are not complete enough for such comparison. Plants grown on the Isabella sandy loam show that all soil treatments containing limestone increased the nitrogen content of both the stems and leaves but tended to depress the phosphorus content. In general, the plants grown on soils not requiring applications of limestone showed increases in the phosphorus content of both the stems and leaves with fertilizer treatments containing superphosphate alone or with potash. Plants from the Gilford loam were markedly higher in calcium content than plants grown on the other soil types studied. Alfalfa grown on Isabella sandy loam soil showed a decidedly higher phosphorus content in both the stems and leaves than that of plants from the other soil types. Plants grown on Montcalm sandy loam soil in the greenhouse required very heavy applications of phosphate in order to increase their phosphorus content materially. The phosphorus content of alfalfa grown on the soil types studied was not low compared to that of alfalfa from other states. The data presented in this paper indicate no advantage of the systematic over the random method of taking samples of alfalfa for chemical analysis.