On 3 Aug 03 at 21:28, Roy Sachs wrote: > Has anyone out there had experience controlling horsetails with > herbicides? > > The more I pull them up the more that rhizome growth is stimulated > rhizome or something wild is happening since the area of infestation > has expanded at least 5-fold in five years. The herbicide MCPA will control horsetail. I do not know if it is still available. By control, I mean about 95% kill. Treat once, wait long enough for surviving rhizomes to re-shoot, then treat a second time. The infestation should then be sparse enough for *digging* of remaining lively rhizomes to be effective, but you still face several years' vigilance. Note that horsetail has paired tubers at intervals along the rhizomes. It is definitely a survivor! MCPA is not a selective herbicide, so the ground must be fallow to use it on horsetail, or contain only weeds. -- Rodger Whitlock Victoria, British Columbia, Canada "To co-work is human, to cow-ork, bovine."