Herbicide tolerance in pasture legumes and herbs

Herbicides are a valuable tool that can be used to facilitate successful establishment of pasture and forage species. Care needs to be taken when choosing which species to include in a pasture mix. This project evaluated the feasibility of using several pre-emergent, post-sowing pre-emergent, early postemergent and late post-emergent herbicides on a range of pasture legume and herb species. TriflurX® and Stomp® both incorporated by sowing, were found to cause minimal damage to most species. All the postsowing pre-emergent herbicides evaluated caused unacceptable damage, except atrazine and simazine on woolly pod vetch. Species varied considerably in their tolerance to post emergent herbicides. The results indicate that it is very important to choose species in a forage mix that have similar herbicide tolerance to maximise the herbicide options available. However, herbicides should not be used as the only option to control pasture weeds. Prior preparation of paddocks through use of cropping or pasture cleaning can greatly reduce weed burdens. An integrated approach to weed control will always be the most successful strategy.