Chemical Control of Sorghum Midge, 1979

Test plots 4 rows wide × 65 ft and replicated 4 times were planted to moisture on April 2’79. Two rows on either side of each plot were previously planted on March 10’79, to promote a midge infestation. Mesurol at 1.0 lb ai/acre used as a hopper-box treatment to repell birds. Six applications of each treatment were applied at daily intervals beginning on May 28’79, to the middle 2 rows of the 4 row plots. A self-propelled, high clearance sprayer delivered 5 gal of finished formulation per acre by means of a CO2 powered system. Adult midge populations were extremely high, averaging 10-30 per head in the untreated plots throughout the test. Treatments were terminated after 6 applications due to rainfall. Efficacy was evaluated for 14 days by recording the number of adult midges which emerged from 5 heads/plot excised 11 days after the initial application and from estimated grain sorghum yields.