Residential Herbicide Guide

Herbicides only work for plants that have not formed thorns. If thorns are already on the vines, an herbicide will kill the plant but seeds inside the thorns drop to the ground and stay alive and viable. This guarantees the infestation will recur.

There are few preemergent herbicides that are effective. Products containing oryzalin, benefin, or trifluralin will provide partial control of germinating seeds. These must be applied prior to germination (late winter to mid-spring). 

After plants have emerged from the soil (postemergent), products containing 2,4-D, glyphosate, and dicamba are effective on puncturevine. The smaller or younger the plant, the better the postemergent herbicides work. If a plant has Dicamba and 2,4-D will injure most broadleaf plants so it is important that they only be applied to the weeds and drift is minimized. Glyphosate will kill or injure most plants so it should only be used as spot treatments or on solid stands of the weed.

*Information from University of California Integrated Pest Management Program