Daily News Archive
From May 20, 2002
USDA Tests Herbicide
The Agricultural Research Service (ARS), chief research agency of the USDA, recently conducted a study showing potential success of vinegar used as an herbicide. This non-toxic alternative has been used to combat weeds for years but never scientifically tested. ARS scientists Jay Radhakrishnan, John R. Teasdale and Ben Coffman set out to change that. They tested the efficacy of vinegar made from fruits or grains against such weeds as Canadian thistle, giant foxtail, velvetleaf, smooth pigweed and common lamb's quarters.
The ARS uniformly coated leaves with varying potencies of vinegar solutions, both in the greenhouse and in the field. Their results were positive, but they did stress a need for more research. They found that a 5 to 10 percent solution could kill younger weeds in the first two weeks of life. An 85 to 100 percent solution killed adult weeds. A 20 percent concentration used in a cornfield killed 80 to 100 percent of all weeds. Here, decreased toxicity goes hand in hand with decreased cost. Spraying the entire field cost $65 per acre. Spot spraying local weed infestations in the cornfield may only be $20 to $30.
The vinegar in your kitchen cabinet is most likely a 5 percent solution. For information regarding least-toxic weed management, please contact Beyond Pesticides.