Studies were conducted to evaluate growth and reproductive capabilities of creeping rivergrass in response to rice herbicide programs. Creeping rivergrass grown from single-node stolon segments, multiple-node stolon segments, and rhizomes was treated with various herbicides to evaluate activity on subsequent growth and viability of nodes produced from treated plants. Comparison with the nontreated, cyhalofop, glyphosate, and imazethapyr reduced creeping rivergrass fresh weight by more than 84 to 96%. Glyphosate reduced sprouting of nodes from treated plants 93% compared with nontreated plants. Activity from these herbicides may decrease when applied to plants grown from rhizomes versus rhizome clusters. Plants treated with cyhalofop, glyphosate, and imazethapyr had reduced fresh weight of 36 to 46% when plants were grown from a rhizome cluster, and 69 to 90% when plants were grown from a single rhizome segment, compared with nontreated. Cyhalofop and glyphosate reduced node sprouting by 81 to 98% of nontreated , regardless of parent structure.

Nomenclature: Cyhalofop; glyphosate; imazethapyr; creeping rivergrass, Echinochloa polystachya (Kunth) A.S. Hitchc.; rice, Oryza sativa L