Field Tests with Thimet and Bayer 19639 for Cotton-Insect Control1

Abstract

Experiments were conducted to determine the effectiveness of seed treatments of Thimet and Bayer 19639, in-furrow applications of granulated Thimet made at time of planting, and side dressing applications of granulated Thimet for the control of cotton insects and the effect on the cotton plant itself. The treatments tested afforded virtually no control of the boll weevil but gave good to excellent aphid control throughout the complete growing period of the plant. There was no evidence that Thimet was taken up or translocated more readily in soils with a lower level of phosphorus. Seed treatments of Thimet and Bayer 19639 adversely affected stands. In-furrow treatments of Thimet did not affect stands. None of the treatments affected plant height. Only one treatment, the Thimet 2-pound in-furrow treatment, adversely affected fruiting. The treatments tested had no adverse effect on grade and staple or on the germination of seed produced with these treatments. Likewise, such properties as fiber strength, maturity, fineness, boll size, seed index, lint index, and per cent of lint were not affected by any of the treatments.