If you have no other planting Glyphosate (trade name; Roundup) should be effective, but is likely to require more than one application. Asulam (trade name; Asulox) is specific for Rumex spp (ie docks) and bracken - some posts say that it is not available for amateur use, and the minimum order (from PitchCare.com) is £75+VAT.
|