EFFECT OF LONG-TERM VETCH (VICIA-VILLOSA) COVER CROP AND TILLAGE SYSTEM ON FLUOMETURON DISSIPATION FROM SURFACE SOIL

This research examined the effect of mechanical soil disturbance (none or tilled) and legume crop residues (none or hairy vetch) on fluometu ron dissipation for 2 yr from the top 0 to 8 cm of soil in a 10 yr fie ld experiment. Soil pH in the upper 0 to 8 cm was less than or equal t o 5.6, and soil organic matter was highest in plots not-tilled and plo ts which had a vetch cover crop. Calculated initial half-lives of fluo meturon ranged from 19 to 38 d in the 2 yr. Neither tillage nor cover crop influenced early-season fluometuron dissipation. However, there w ere detectable amounts of fluometuron in all treatments 1 yr after app lication.