METHIOCARB AS A BIRD REPELLENT ON RIPENING GRAIN SORGHUM

Abstract

Bird damage on grain sorghum (Sorghum bicolor (L.) Moench) crops in the United States is a multimillion dollar problem. High tannin, bird-resistant sorghum hybrids provide a non-preference type of resistance, the effectiveness of which is governed by size of bird populations and availability of other food sources. However, high tannin grain can result in nutritional and marketing problems. Chemical control agents provide alternative means of reducing bird damage. This study, by measurement of grain yield and bird damage, evaluated the bird repellency of methiocarb applied to grain sorghum at three rates. Grain yields were 1383 kg/ha (28%) higher and bird damage was 37% lower on the methiocarb-treated plots than on the check plots. Test weight was 1.2 kg/hL higher and plants were 6 cm taller on the treated plots than on the check plots, suggesting a possible growth stimulatory reaction. An application rate of 1.2 kg/ha of 75% wettable powder appeared to repel birds as effectively as higher rates. Grain yields were substantially reduced (from 8104 to 4894 kg/ha) as the rate of methiocarb treatment increased from 1.2 to 4.26 kg/ha.