Herbicide Interactions in Control of Sand Shinnery Oak

Abstract

Silvex was the most effective herbicide for reducing sand shinnery oak (Quercus havardii Rydb.) density and increasing grass production in the Rolling Plains of Texas. Combinations of silvex or 2,4,5-T with picloram controlled more sand shinnery oak than expected (synergistic) and substantially increased grass production. Picloram and 2,4-D (1:1) at 0.5 lb./acre total were additive and less effective than other phenoxy:picloram combinations. Combinations of dicamba with 2,4,5-T or silvex were usually additive.