Alfalfa Foliar Sprays for Potato Leafhopper Control, 1977

A 2 year old stand of Saranac AR alfalfa in Montgomery County, Virginia was used to assess insecticide efficacy on potato leafhoppers. Eight treatments (40 x 40 ft) arranged in a randomized block design with 4 replicates were compared to an untreated check. Insecticides were applied to 16 in. alfalfa on August 4 with a hand-carried compressed air sprayer at a rate of 20 gallons per acre at 40 psi. Potato leafhopper nymphs and adults were sampled 48 hr, 1 wk, and 2 wk after treatment. Two sets of 15 sweeps from each block were taken using a 180° sweep with a 15 in. sweep net. The total number of leaf-hoppers counted in each sample was transformed to Log (X+ 1) for analysis. Yield and green weight were taken on August 25 at 25% bloom with a flail forage harvester using a 3 x 20 ft swath per plot. Percent dry matter was also measured.