Brittany Utsch Abstract- Oil Adjuvant.

The performance of several herbicides such as clethodim, saflufenacil, aciflurofen, fomesafen, topramozone is increased with the use of an oil type adjuvant. Weeds have become resistant to glyphosate. Applicators are tank mixing several herbicides with glyphosate to control these resistant weeds. Oil adjuvants are generally not recommended for use with glyphosate. Studies were conducted to determine the influence of several different oil adjuvants on the performance of tank mixes with glyphosate plus certain oil loving herbicides. The oil adjuvants include crop oil concentrates (COC), modified seed oils (MSO), high surfactant oil concentrates (HSOC), and methylated seed oil high surfactant oil concentrates. Trials were conducted with glyphosate plus each of the following herbicides; clethodim, saflufenacil, aciflurofen, fomesafen, and topramozone. Reduced rates of the herbicides were used to enhance the differences in performance due to the adjuvants. Treatments were applied with a backpack and hand boom applicator at ten or 20 gallons per acre to actively growing crops and weeds. These studies were conducted using randomize complete block designed with four replications. At least two weed control ratings were collected. Collecting timings were seven and 14 days after treatment and some trials had a 28 day rating also. Oil adjuvant type influenced the performance of the herbicides tested. Oil adjuvants increased or tended to increase the weed control with the oil loving herbicides. The performance of the glyphosate was influenced by some of the adjuvants systems.