2008 Joint Annual Meeting (5-9 Oct. 2008): Up and Coming Organic Herbicides.

630-3 Up and Coming Organic Herbicides.



Tuesday, 7 October 2008
George R. Brown Convention Center, Exhibit Hall E
Charles L. Webber III1, James W. Shrefler2, Merritt J. Taylor2, Lynn P. Brandenberger3 and Rick A. Boydston4, (1)USDA-ARS, SCARL, PO Box 159, Lane, OK 74555
(2)Oklahoma State University, P.O. Box 128, Lane, OK 74555
(3)Oklahoma State University, Stillwater, OK 74078
(4)USDA-ARS, 24106 N. Bunn Rd., Prosser, WA 99350
In a recent national survey, weed control research was designated as the top research priority by organic producers.  Organic weed control methods include crop rotations, cover crops, planting systems, mulches, mechanical methods, flaming, and organic herbicides.  Although mechanical weed control through cultivation is useful for controlling weeds between rows, it is ineffective for controlling weeds between plants within rows.  Very few chemical weed control options have been approved for organic use (corn gluten meal, vinegar, and clove oil), but additional compounds are under investigation and pursuing organic certification.  As with corn gluten meal, mustard meal has shown promise as a preemergence herbicide.  A formulation of pelargonic acid, a fatty acid, has proven effective as a postemergent herbicide, but the specific formulation still seeks final approval. Ammonium pelargonate is another potential organic herbicide that has shown excellent weed control activity and is presently waiting for approval as an organic herbicide.  Additional active ingredients and variations in formulations are also being developed, entering initial greenhouse screenings, and progressing to extensive field evaluations.  Even if all these active ingredients and their commercial formulations are registered by EPA and approved through the organic approval process, the application technology and timing will play an essential element in their successful integration into existing certified organic systems.