Consider Fall Herbicide Application for Pasture Weed Control
October 12, 2011
While daytime temperatures are still in the 60s and 70s, and plants are actively growing, is the best time to apply herbicides to control pasture thistles, according to your local county USDA-Natural Resources Conservation Service (NRCS) office.
Fall herbicide application offers several benefits over spring application. These include:
Herbicides move readily from the foliage to the roots with the sugars because thistles are building up root reserves in the fall. In the spring, carbohydrates move from the roots to the leaves so less downward herbicide movement would occur.
Biennial thistles will be controlled because any shoots present in the fall are in the rosette stage and thus are very susceptible to herbicides. Even if the herbicide does not totally kill the plants, winter weather will finish what the herbicide starts.
Land managers may have more time to treat infested sites in the fall than during the rush of spring and early summer field activities.
Finally, with fall treatment there are fewer risks that herbicide drift will injure nearby sensitive crops like soybeans as these have already matured.
Pasture weed control is an important management consideration as thistles compete with desirable grass and legume species as well as contribute to under utilized areas of pastures when livestock avoid the spiny plants.
All herbicide applicators are responsible for using herbicides in full compliance with the current product label. For more information, please visit your local NRCS office.