Susceptibility of great bindweed (<i>Calystegia silvatica</i>) to herbicides

Abstract

A field trial was conducted in Palmerston North to compare autumn applications of several translocated herbicides for great bindweed (Calystegia silvatica) control in riparian zones Regrowth in the following spring showed that a triclopyr/picloram/ aminopyralid mixture a 24D/dicamba mixture and aminopyralid by itself were the three most effective treatments though none gave complete control Glyphosate provided partial control whereas metsulfuron and clopyralid provided poor control These and two other herbicides were further assessed in a glasshouse trial in which they were applied to leaves either on the upper or lower half of plants to compare efficacy The relative effectiveness of these herbicides on great bindweed was similar to that found in the field Most herbicides had similar efficacy whether applied to upper or lower parts in autumn except glyphosate which was more effective applied to upper plant parts Implications for control of great bindweed in riparian plantings are discussed