EFFECT OF CROP RESIDUES AND FERTILIZER TREATMENTS ON THE YIELD AND PROTEIN CONTENT OF WHEAT

Results are presented showing the effect of alfalfa, grass and wheat crop residues on the yield and protein content of wheat during the 6-year period, 1948–1953.The yield of first crop wheat after alfalfa (34.4 bu./ac.) was greater than the yield after grass (25.6 bu.). The yields of wheat after fallow in which wheat straw residues had been incorporated were 31.4 and 32.4 bu. The second wheat crop after alfalfa (23.8 bu.) yielded more than the second crop after grass (19.4 bu.) and also than the second crop after fallow (18.4 and 16.3 bu.)Returning wheat crop residues reduced yields. This effect was slight the first year after fallow but more pronounced the second year after fallow. The depressing effects of grass and wheat crop residues were partly offset by applications of 16-20-0 at 108 lb. per acre. Yields of the second crop of wheat after fallow were greater where sweet clover had been ploughed down in the fallow year or where the straw residues were burned.The protein content was highest after alfalfa and where sweet clover was ploughed down in the fallow year. Protein content was low after grass breaking. Fertilizer treatments, although they increased yield, had little effect on protein content.