Rice Water Weevil Control, 1981

Rice was planted Apr 28 in Crowley silt loam at the Rice Research and Extension Center, Stuttgart, AR. Both tests were arranged in a randomized complete block design with 4 (Test I) or 3 (Test II) replications. All plots were sampled for root-feeding larvae by taking 5 soil cores (9 cm dia x 7 cm deep) from the drill rows of each plot; they were processed by washing through a #40 U.S. Standard soil testing sieve and floating the larvae out in brine. Test I: Insecticides (all granular) were applied by hand shaker Jun 10 to plots measuring 5 x 15 ft. The test was flooded Jun 11 and sampled Jun 30. Test II: Plots were 5 ft in dia and enclosed by aluminum flashing to prevent water movement. They were flooded on Jun 12 and the weevil population supplemented by the addition of 68 weevils per plot on Jun 17. Treatments were applied as follows: SIR-8514 and FCR-1272 were applied with an AZ CO2 powered sprayer until the spray mixture ran off the plants (1 qt per plot); Ammo, Pounce, Cymbush, and Ambush were applied to the water surface in a hydrocarbon (Exxon 4543) at 1 gal/acre; Furadan and Oncol were applied by hand shaker. Larvae were sampled Jul 1.