Absorption, translocation, and metabolism of 14C-triclopyr were compared in the rice cultivars ‘Lemont’ and ‘Tebonnet’ under flooded and non-flooded conditions. Radioactivity washed from 14C-triclopyr-treated leaves was 26% at 6 h and decreased to about 11% of that applied at 96 h after treatment. Triclopyr was immobile with 98% of the recovered 14C remaining in the treated rice leaf. An average of 19% of triclopyr was metabolized at 6 h and was similar among flooded and nonflooded rice cultivars. Absorption, translocation, and metabolism of triclopyr did not differ among rice cultivars or flooding treatments.

Interference from broadleaf signalgrass at a density of 180 plants/m2 reduced rough rice yields of ‘Bond’ a maximum of 48% at 95 days after rice emergence and reduced yields of ‘Mars' a maximum of 21% from season-long interference. Interference durations of 40 days or longer reduced the panicles/m2, culms/m2, and plant height of rice. Straw dry weight of Bond and Mars was reduced 41 and 26%, respectively, from season-long interference. Increased durations of weed interference did not affect the number of spikelets/panicle, percent filled spikelets, rough kernel weight, or head rice yield of either cultivar. Broadleaf signalgrass produced less dry weight and fewer panicles/m2 when grown with Mars than with Bond.