Agronomy Library > Disease

Pre-harvest Applications of Glyphosate for Weed control and Harvest Management
Author: Mirza N. Baig & Peter M. Gamache
Date Created: July 12, 2006
Last Reviewed: July 30, 2007
Canada thistle, dandelion, quackgrass, and perennial sow thistle are among the top 20 commonly occurring weeds in Alberta (Leeson et al 2001). Control of these weeds in the spring or fall is difficult because of (1) insufficient weed regrowth, (2) wet conditions in spring or fall, and (3) late and/or early, heavy, killing frost. Pre-harvest applications with glyphosate may be applied to barley, oats, wheat, oilseed, pulse and forage crops for the control of annual and perennial weeds. These applications also provide crop dry down by killing all the green weeds; by harvest time they have died-back, thus reducing the amount of green matter in the crop. In addition to speeding the harvest, a pre-harvest application also provides a drier, cleaner sample and reduces grain losses through the combine. This treatment should not be applied to crops if grown for seed production.  Click the pdf above for the complete 4-page factsheet.