Integrated Weed Management Strategies to Increase Pasture Productivity

Problematic weeds such as tall ironweed, musk thistle, spiny amaranth, buttercup, common cocklebur, and horsenettle have been increasing in pastures during the past several years as grazing has intensified within Kentucky, Tennessee, and the surrounding region where cool-season grasses are the predominant type of forages grown. These weeds are becoming more prominent in pastures because they are unpalatable to animals or have spines or thorns. Livestock producers are seeking ways to increase pasture productivity by minimizing the impact of these weeds on grazed lands. One of the primary methods used to combat weeds in pastures has been mowing, but due to increasing energy cost producers are beginning to question the economic viability of this option. Other weed control methods which are available including integration of weed management practices need to be considered. The objective of this project is to evaluate mowing (mechanical control), herbicide (chemical control), and added fertility (culture practice) as independent factors and as integrated weed management methods that best reduce populations of unpalatable weed species which compete with the productivity of desirable forage species in grazed pastures. Field research trials will be used to determine pasture productivity relative to these weed management strategies combined with an economic analysis that would assess the cost/benefits of each of these different weed management practices. During the final stages of this project field days will be held, meeting presentations and publications will be used to educate livestock producers, county extension agents, and other interested individuals on best management practices for weed control in pastures.