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Herbicide Residue And Weed Control In Switchgrass, Charles Nicholas Smith Jr.

Electronic Theses and Dissertations

Purposes of this study were to find an effective herbicide for control of grassy weeds in a pasture, to adapt known laboratory procedures for analyzing residues and to determine amounts of residues during the growing season in treated plots. Nine herbicides were screened for controlling grassy weeds, primarily downy brome (Bromus tectorum L.) in a native pasture. Data indicated 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine) applied postemergence at 1 lb/A was the most effective at 85% control. The following year, atrazine, 2-chloro-4, 6-bis­ (ethylamino)-s-triazine (simazine) and 2, 2-dichloropropionic acid (dalapon) each at 1, 2 and 3 lb/A were applied preemergence to switchgrass pasture. Of …