Author
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Hanks, James |
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WILLS, G - DREC |
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JONES, E - DREC |
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MACK, R - HELENA CHEMICAL CO. |
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Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Abstract Only Publication Acceptance Date: 1/23/2000 Publication Date: 1/25/2000 Citation: Hanks, J.E., Wills, G.D., Jones, E.J., Mack, R.E. 2000. Adjuvants for drift control of roundup ultra herbicide. 2000 Proceedings of Southern Weed Science Society. 53:208. Interpretive Summary: Abstract, summary not required. Technical Abstract: Field and laboratory studies were conducted to determine the effect of ten experimental drift retardants on the efficacy, spray pattern, and droplet size of Roundup Ultra spray solutions. The herbicide was applied in the field at 0.5 lb ai in 10 gpa at 43 psi using a tractor-mounted sprayer with TeeJet extended range 110015VS nozzles. Field-plot applications were to 4 4rows of three trifoliolate stage soybeans (Glycine max L.) 'ASGROW 5901RR' spaced 38 inches apart, 40 feet long and interspaced with 4- to 6-inch-tall barnyardgrass [Echinochloa crus-galli (L.) Beauv.], 4- to 6-inch-tall pitted morningglory (Ipomoea lacunosa L.), 2- to 4-inch-tall prickly sida (Sida spinosa L.), and 6- to 10-inch-tall smooth pigweed (Amaranthus hybridus L.) arranged in a randomized complete block design. Spray patterns were determined using a single nozzle by applying 600-ml volumes of spray mixtures at 43 psi, similar to that of field applications, to a slanted sheet of corrugated metal with troughs spaced 2.5 inches apart and collecting in 100-ml graduated cylinders. Spray droplet size was determined using a Malvern 2600 Lc laser particle analyzer at 40 psi. The most effective drift retardand mixed with Roundup Ultra which resulted in the greatest percent weed control, the greatest percent volume of spray droplets larger than 105 microns and an acceptable controlled spray pattern was HM 9752. |
