DIY
Epsom salt method
The Epsom salt method is a home trick of filling drilled holes with Epsom salt to dry out or rot a stump, and extension sources do not back it.
Ask Extension, a national extension question service, received a question about drilling holes in a stump and filling them with Epsom salts. The answering specialist said that if research has been done on this claim, it is not readily accessible, and that this is not a recommendation they would support.
The specialist guessed a concentrated application might dry out live stump cells, but doubted how it would work once the tree is cut. University of Illinois Extension says that stump chemical treatments are usually salts, such as potassium nitrate, and that they are meant to dry the wood for burning. Compare stump killer and natural decay. The post on the Epsom salt stump myth goes further.