A video showing how the Stihl Brush Knife works on tall weeds. The brush knife is being powered with a Stihl FS 90R trimmer with blade mounting kit and barrier bar attached. The brush blade works good on tall grasses, weeds, sticks, and light brush and brambles. Using a weedwacker with any attachment, whether it be a blade or string trimmer head, is dangerous. Be careful and do it at your own risk.