Control of Live Oak in South Texas

Abstract

Aerial applications of herbicides were made in May, July and November, for control of live oak (Quercus virginiana Mill.) in South Texas. Single or repeated applications of (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) at 2 lb/acre did not satisfactorily control live oak. However, 4-amino-3,5,6-trichloropicolinic acid (picloram) at 1 or 2 lb/acre applied in May 1964 and retreated in May 1965 effectively controlled live oak (93 and 98%, respectively). Single applications of picloram at 2 and 4 lb/acre and a mixture of picloram + 2,4,5-T at 2+2 lb/acre were effective when applied in November 1965. Summer applications of picloram and picloram + 2,4,5-T required a repeat treatment for best results.