July 31, 2009

Glyphosate Benchmark Study

The fifth installment of the glyphosate use benchmark reports.

Weed scientists from six universities have joined forces to examine grower weed management practices and develop programs to evaluate and improve the sustainability of weed control in Roundup Ready® cropping systems. Called the Benchmark Study, this multi-state research project is now in its fourth year. Funding for the study has been provided by the Monsanto Company.

This week's report shares the results of a survey of growers regarding their awareness of glyphosate use and resistance development:

• Awareness for the potential of weeds to develop resistance to glyphosate herbicide ranged from 75 to 88% of growers depending on the farm size.
• Awareness and concern for glyphosate resistance was slightly greater for growers with medium to large farms.
• Approximately 30-40% of the growers were aware of glyphosate resistant weeds in their state. However, only 30% or less of all growers surveyed believed glyphosate-resistant weeds were a serious agronomic issue (data not shown).
• A relatively low percentage of growers (13-19%) had personally experienced glyphosate-resistant weeds on their farm. However, 43-65% of growers had taken actions to minimize glyphosate resistance.

Robert Wilson
Mark Bernards
UNL Extension Weed Specialists with the Benchmark Study