Formulation, Rate and Season and Application Effects of Hexazinone (Velpar) Gridball on Oak Topkill

Abstract

Hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-l,3,5-triazine-2,4(1H,2H)-dione] gridball was tested for site preparation on a loamy sand soil. The gridball was applied in the 1 and 2 cc formulations at 0.56, 0.84 and 1.12 kg ai/ha in a completel~y randomized design with three replications in April, June, and August 1978. After two growing seasons the 1 cc gridball had a slight performance advantage over the 2 cc gridball for the April application, but overall oak (Quercus sp.) topkill from the 1 cc gridball was not significantly different from topkill caused by the 2 cc gridball. Only the highest rate applied approached the minimum acceptable topkill level of 80%. The April and June applications gave similar results, and both were better than the August application. The Alabama 24-C label probably needs to be changed to allow higher application rates for site preparation on loamy sand soils.

Citation

Michael, J.L. 1980. Formulation, Rate and Season and Application Effects of Hexazinone (Velpar) Gridball on Oak Topkill. Proc. South. Weed Sci. Soc. 33:110-113. 1980