I worked for the US Forest Service in the late 70s , my job was to kill certain trees, I had a hypo hatchet which was a hatchet with a hole in each side of the blade the head has a spring loaded piston in it , the handle was hollow and a hose ran from they handle to a qt bottle you wear on you belt , we used Tordon, chopped a continous ring completely around the tree and it would be dead in less that a week.
