Screening herbicides for the control of the wetland invader, Sambucus nigra L., in South Africa

Abstract

Information on the management of Sambucus nigra L. is lacking, but clearing operations are going ahead with unregistered herbicides that might not be appropriate for use in wetlands or effective against S. nigra. The objective of this study was to test the efficacy of five common herbicides applied to S. nigra stumps and coppice and to provide mortality data for registration purposes. Fluroxypyr/picloram 80/80 g l⁻¹, imazapyr 100 g l ⁻¹, metsulfuron methyl 600 g l⁻¹, picloram 240 g l⁻¹ and triclopyr 480 g l−1 provided >80% control/mortality at the lowest concentrations tested compared to untreated stumps and coppice, which had 29 and 20 % mortalities, respectively. All the herbicides tested are suitable for controlling S. nigra in non-drainage areas, but picloram is prohibited in wetlands. This information will be helpful in making appropriate herbicide choices for S. nigra control.

Keywords: coppice, efficacy, elderberry, elders, fluroxypyr/picloram, metsulfuron methyl, spray, stump, triclopyr