Goat Weed has taken over our horse pasture. It's horrible. I don't know if this stuff is an annual or perennial, or how it spreads. Am wondering if it is too late to spray it now (Sept. 1) to be time- and cost- effective? We sometimes get a light frost in October. Am wondering if it dies off for the season when it frosts. Usually don't get a freeze 'til mid-December, though our weather has been erratic to the extreme the past few years here in Zone 8a/7b East Texas.

If it is advised to go ahead now and spray, can horses stay in the pasture, and if not, when can they go back in? Also, what herbicides are recommended?

Also, when is best time to spray for this stuff? Is early spring recommended or should we wait for it to show itself?

Sincere thanks for any help.

Ann