Evaluation of Very Low Rate Aerial Application of Dimilin for Rangeland Grasshopper Control, 1992:

Dimilin 2F and Sevin XLR were applied to a rangeland site in Platte County, Wyoming. Treatments were randomly assigned to 15, 48.3 acre (19.5 ha) plots, with three replicates. Treatments were aerially applied on 17 Jun. During application the temperature never exceeded 24° C and humidity was low. Grasshopper densities were estimated in each plot by using 27, visualized ft2 samples; species and age composition were determined by taking 50 sweeps with a 30.5 cm diam sweep net. These sampling procedures were conducted seven d prior to treatment and 7, 14, and 21 DAT. Fisher’s protected LSD post-ANOVA test was used to evaluate differences in grasshopper densities at each sampling time. One replicate of Dimilin (0.25 oz) was excluded from analysis due to application error. Cumulative mortality rates were calculated after correcting for mortality and development in the untreated control plots.