we have about a acre and a half of it and we havnet had much trouble keeping it where we want it. the sale only works if you pour lots of it on it. and I mean LOTS. the best thing to corrall it up with and keep it contained is to dig a ditch around it and put tin in the ditch .( tin sheets on their sides ) then put the dirt right up to it. the roots will grow into the tin and hit it and turn up . it will not grow any futher if you have the tin deeper than the roots. we use it for many many things and have some lots of it to people for crafts, fishing poles, garden stakes, trelles, to cover a roof. this stuff has tons and tons of uses. we make pretty good off of it in the spring selling the shoots to asian people who pickel it , can it . they say it taste really good but I have not ate any of this but have ate it at different chinese buffets.