Repeated, Foliar Applications of MSMA on Purple Nutsedge

Repeated, foliar applications of monosodium methanearsonate (MSMA) controlled established, space-planted purple nutsedge (Cyperus rotundusL.) while three other herbicides were less effective. Four to eight applications of 5.6 to 16.8 kg/ha of MSMA in 1 year destroyed most plants. There was little difference in final control from applications made at 2, 3, or 4-week intervals or from 187 to 1496 L/ha of spray solution. Clones of purple nutsedge responded similarly to herbicide treatments.