In separate, replicated experiments, we experimentally established wash-off coefficients (kw) for the chemical agent VX on grass, utilizing 1 and 3 L VX droplets at 0.017 (1 min), 1, and 4 h after dissemination. A 10 mm (0.39 in.) rain event at 0.017 h after dissemination washed off 95 and 83% of the 1 and 3 L VX droplets, respectively. At 1 h after dissemination, a 10 mm rain event washed off 0.03 and 0.5% of the 1 and 3 L VX droplets, respectively. At 0.017 h after dissemination, the kw values for 1 and 3 L droplets were 0.095 and 0.083 mm1, respectively. At 1 and 4 h after dissemination, the kw values for VX were approximately 3 orders of magnitude less than those at 0.017 h. Grass contaminated with 3 L VX droplets was exposed to multiple (10) 100 L light rain events, followed by multiple (10) surface wipes at 0.017, 0.5, 1, 4, and 24 h after dissemination. The cumulative proportions of 3 L VX droplets washed off by the rain events at 0.017 and 1 h after dissemination were 75.3 and 0.99%, respectively, and the cumulative proportions of VX wiped off after those rain events were 0.8 and 0.3%, respectively. Results from these investigations of agentplant interactions provide input for predictive models and functional information for Go/No-Go decisions that can affect soldiers on agent-contaminated battlefields.