Crop Reserve Grasshopper Control, 1990

Low profit potential of land used in the crop reserve program is sometimes exasperated by the needs to treat grasshopper outbreaks which have the potential of moving into adjacent row crops. To determine an effective and economically acceptable rate of insecticide, we established plots (63.7 by 63.7 m; 0.4 ha) with several rates of proven grasshopper insecticides (28 Aug) with an untreated check arranged in checkerboard fashion, which allowed grasshopper immigration into treated plots from all four directions. Applications were made with Broyhill sprayer delivering 10 gal/acre at 40 psi using Teejet 8002 nozzles. A randomized complete block design was used with 4 replications. Forty rings (0.1 m2) were placed in 4 parallel rows in the central portion of each plot. Grasshopper counts (0, 7, 14, 21 and 28 DAT) were used to calculate the percent reduction. No significant differences were detected between compounds, or application rates during the 28 DAT. The control offered by all insecticides and rates was highly successful, which suggests that the residual of these pesticides remains effective even at the lowest rates. Therefore, the lower rates are favorable to the farmers needs for control and economy.