Cut the tree down to a stump, making sure the surface is as smooth as possible to keep the chemical from flowing off. Remove all sawdust from surface. A chain saw or ax works best for taking down the tree.
Spray the entire stump surface with glyphosate herbicide to kill all the way down to the roots, according to the Washington State University Extension. Follow the product label instructions for application details. The chemical will be translocated to the roots by the tree's tissues.
Treat the entire surface on trees that are 3 inches or less in diameter. On larger diameter stumps, treat only the 2 to 3 inches next to the bark.
Spray the stump with the herbicide after cutting on fresh wood for best efficacy. If you were not able to treat the stump right away, make a fresh cut before applying the glyphosate.
Remove the dead stump by grinding it down to 1 foot below the soil line or removing it entirely by wrapping a chain around the stump, hooking the chain to a truck or tractor, and pulling it out.