dixie, the best tree killer is triclopyr. This used to be the active ingredient in Ortho's Brush-B-Gon. I am referring to the concentrated form, generally about 8% active ingredient, not the premixed types. Not sure if it is still available. Have also seen the Enforcer brand of brush killer to be 8% triclopyr. When cutting down a weed tree, make your lowest cut a perfect horizontal. If you flood this stump with the full strength triclopyr-based product, you will have a 95% success rate in stump killing. If you drill several large holes into the stump, and fill these as well as the flooding, you will probably have a 100% success rate. (Probably, because nothing in nature is 100%, or it wouldn't be nature.) We have large eyedroppers for application in the holes. You can kill a standing tree by drilling into it in a downward angle and injecting the herbicide. But it is usually easier to cut down a living tree than a dead one, so we do the stump treatment. If you do kill the tree first, be sure to cut it down soon after. Dead tree is harder wood if it sits very long.