Responses of Falsemesquite, Native Grasses and Forbs, and Lehmann Lovegrass after Spraying with Picloram

Abstract

Aquecus sprays of picloram at the rate of 0.56 kg/ha (94 1/ha total volume) were applied to 5 plots each in May 1973 and August 1976 to control falsemesquite (Calliandra eriophylla) in southern Arizona. Falsemesquite was effectively controlled on both spraying dates. The greatest vegetation change on sprayed and unsprayed plots alike was the overwhelming natural increase in density and yield of Lehmann lovegrass, an introduced species. Perennial forbs were almost completely eliminated and densities of native perennial grasses were greatly reduced both on treated and untreated plots.