Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/12/2008
Publication Date: 2/19/2009
Citation: Shaner, D.L., Khosla, R., Helms, A., Boseley, B. 2009. Enhanced Atrazine Degradation: A Survey of Crop Fields in North-Eastern Colorado. Weed Science Society of America Annual Meeting - Abstracts. orlando Florida February 9-12, 2009 Interpretive Summary:
Technical Abstract: When it comes to weed management, logically, farmers have a very low tolerance for weed infestations since it can cause significant damage to their crop yields. However, over application of pesticides for any infestation has a serious consequence. Recently, farmers in the north-eastern Colorado reported that atrazine was not giving the residual control as expected. This could be a cause of concern for many reasons because atrazine is widely used in Colorado for controlling many broadleaf and certain grass weeds in corn (Zea mays L.) and other crops. A survey was conducted in 2007-2008 to determine the extent of fields showing enhanced atrazine degradation. Soils were collected from several fields in various counties, such as Kit Carson, Larimer, Logan, Morgan, Philips, Washington, Weld and Yuma counties. Soil samples were collected from the fields had been planted in maize, wheat or were fallow at the time of collection. Our soil analysis indicates that approximately 30% of the fields tested showed enhanced atrazine degradation. All of the fields with enhanced atrazine degradation had a history of atrazine use. Our survey findings suggest that atrazine degrades rapidly in fields in Colorado where the herbicide has been continuously used for 3 or more years. This rapid degradation leads to loss of residual weed control as reported by farmers.