Harnett County,
North Carolina

Do chemical "stump removers" really work?
 

ASK THE HORT AGENT

Question Do chemical “stump removers” really work?

Answer If left alone, a tree stump will gradually decay in the ground. Natural fungi and bacteria (collectively known as microorganisms) break down the stump which is composed primarily of carbon. This process is the same as the aerobic decomposition in a compost pile and can take from one to many years. Factors affecting the rate of decomposition include size of the stump, species of tree, and soil conditions. This process of decay can be sped up by giving the microorganisms what they need – water, carbon, nitrogen and oxygen.

Piling soil or compost over the stump gets the microorganisms to their dinner table. The wood in the stump provides the carbon. Keeping the soil moist in the area helps to wet their whistle. The addition of a nitrogen fertilizer will also help speed up the process.

Chemical stump removers have been designed to speed up natural decomposition by supplying the microorganisms with nitrogen. Potassium nitrate (KNO3) is usually the primary ingredient used to supply the nitrogen. When potassium nitrate decomposes, it releases another essential ingredient - oxygen. The release of oxygen is beneficial to the microorganisms since a stump cannot be turned (aerated) like a compost pile.

Potassium nitrate has been used as the oxygen-supplying component in gunpowder since the 12th century, which reminds me of another way to get the tree stump out - kaboom! (This is probably not advisable in this age of litigation and homeland security.) Commonly known as saltpeter, potassium nitrate is used in explosives, fireworks, model rocket propellants, matches, and fertilizers. It is also used as a preservative in foods (especially meats), as a desensitizer in toothpaste, and in the manufacture of glass and ice cream. Potassium nitrate works on many things.

Stump removal is the final step in the removal of a tree. The method chosen to get rid of the stump will depend on the use of the area and the time frame desired. If the slower approach is acceptable, consider simply adding some fertilizer, burying the stump in soil or mulch, and letting nature do the job for you. Chemical stump removers work, but they are still considered slow.

For a great site on stump removal methods, check out http://www.urbanforestrysouth.org/Resources/Library/Citation.2004-05-28.0701/at_download/file_name If you don’t have internet access, call the Extension Office at 893-7533, write us at PO Box 1089, Lillington, NC 27546, or email me at gpierce@harnett.org

In One Flew Over the Cukoo’s Nest, Jack Nicolson’s character was worried about the nurse “slipping” salt peter to the hospital patients. http://www.movieprop.com/tvandmovie/reviews/oneflewover.htm A popular misconception is that potassium nitrate (saltpeter) is an anaphrodisiac and was added to food in all-male institutions. Although it may have been used, potassium nitrate has no such effect in humans. I guess the chemical stump removers don’t work on everything.

Gary L. Pierce

Horticulture Extension Agent

Harnett County