Spittle Bugs in Relation to Alfalfa Seed Production in Wisconsin

Abstract

The spittle bug, Philaenus leucophthalmus, and its vars. are economically important in many Wisconsin alfalfa fields. The feeding of nymphs and adults causes a characteristic bunchy-top condition of the plants. The feeding of adults on immature seed pods results in shriveled seed. Applications of Sabadilla, nicotine, and rotenone were not significantly effective in reducing nymph populations, but a trap strip dusted with 5% DDT at the rate of 70 lb. per acre was accompanied by a marked increase in yield of seed even though the apparent reduction in spittle bug adults was not great.