FIELD PERSISTENCE AND MOVEMENT OF TRIFLURALIN IN TWO SOIL TYPES

Abstract

Trifluralin (α, α, α-trifluoro-2, 4, dinitro-N, N-dipropyl-p-toluidine) was applied in 1973 to Egam loam and Beason clay field plots, which differed in slope and texture of the surface 12 in. of soil. Recommended (1×) and excessive (1.5× and 2×) rates of trifluralin were applied, and the herbicide was incorporated to a depth of 4 in. Movement of trifluralin below the 8-in. depth was essentially nil in both soils, but considerable movement occurred to the 8-in. depth in both. Trifluralin longevity in each soil was essentially the same, although higher rates were applied in the clay soil. On the average, less than 1% of the herbicide remained 5 months after application; an increasing trend of trifluralin residues with 1.5× and 2× rates was discerned, however. No herbicide was found in the soil the following spring (11 months after application). There was some evidence of upward movement of trifluralin in both soils. Trifluralin degradation followed first-order kinetics with half-life values of 35.8 and 25.7 days for Egam and Beason soils, respectively. Five weeks after herbicide application, control of two broad-leaf weeds and one grass weed was poor, being consistent with low herbicide concentrations (0.06 ppm) remaining in the soil at that time. The growth of oats (Avena sativa L.), a species sensitive to trifluralin, was also not significantly affected in the greenhouse at 0.05 ppm of trifluralin concentration.

Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.