Weed Management in Plantings of Tree and Shrub Seedlings with Sulfometuron Methyl (Oust)

Sulfometuron methyl (Oust) at two rates was evaluated for use as a weed control agent with 26 broadleaf and coniferous species. Herbicidal application over newly planted seedlings is desirable to reduce weed control costs. Both rates (0.14 and 0.28 kg ai/ha) provided excellent control of broadleaf and grass weeds. Nearly all tree and shrub species exhibited some leaf damage; however, limited tolerance to the lower rate was exhibited by 18 species. Lower rates are suggested for both good weed control and injury tolerance, especially with band application and interrow cultivation.