Vitax sbk brushwood killer is a selective weedkiller for brambles nettles dock woody weeds hardwood saplings and tree stumps in grass and other neglected non crop areas it does not kill grass its active ingredient is triclopyr which is unusually effective on woody plants and is used for brush control in rights of way and defoliation of wooded areas it is also effective against broadleaf weeds particularly creeping charlie apply from may to october june to august for woody weeds when the soil is