Increasing Red Clover Yields by Treatment with DDT or Hexachlorocyclohexane

Abstract

In an attempt to determine the extent of insect injury to red clover and to ascertain the hazards due to insecticide residues, triplicate plots 40 by 40 feet were treated with DDT dusts at 1, 2, and 3% strengths and with hexachlorocyclohexane containing 1, 2, and 3% mixed isomers. Following 2-4 applications of these materials, it was found that the hay yield (dry wt.) was increased in every instance, the amt. of increase varying from 6 to 11%. No toxic symptoms were observed in cattle fed the hay but DDT concns. varying from 0.22 to 0.92 ppm. were found in the milk of such animals. A clover weevil, Hippera meles, and the meadow spittlebug, Philaenus lencophthalmus, were significantly reduced in numbers by all treatments.