Until 1936 the grasshopper problem had never been considered of major importance over the cotton producing area of Arkansas. It had been recognized as of occasional importance in the northwestern counties where cotton is not grown, but only rarely of even local importance in the other parts of the state. In 1936, however, grasshoppers attracted general attention over the northern part of the state, and in 1937 they were the most destructive insect pests in the delta counties of northeastern Arkansas. During the past season, 1938, the injury was less acute than in 1937 but grasshoppers were recognized as destructive enough to justify control campaigns in 25 counties. The greater part of the injury was caused by a single species, the differential grasshopper, Melanoplus differentialis (Thos.).