INTEGRATED MANAGEMENT OF SILVERLEAF NIGHTSHADE

Silverleaf nightshade is a deep-rooted summer perennial weed of southern Australia. Chemical and physical control tactics used for the past half century have not always been successful due to the resilience of the root system. Multi-year experiments established near Culcairn, NSW and Leeton, NSW showed that herbicides can reduce annual stem regrowth by up to 90%, depending upon the herbicide used and the time of application. Herbicide treatments containing the active ingredient picloram were the most effective, particularly if applied annually in summer and autumn. Competition from the perennial sub-tropical pasture species finger grass and digit grass at a field site at Wellington, NSW provided 94% suppression of silverleaf nightshade after two seasons.