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-----:Tree stump killers
Quickstart:
Professional stump grinding, when possible, is probably the best method for dealing with large stumps.
One alternative is putting copper nails in the stump, but it is slow and of unreliable effectiveness, and best suited to rather small stumps.
Copper sulfate is a chemical which may be harmful to other plants or animals, and is discouraged. Other vegetation killers also pose risks to other living things.
The most effective way to accelerate rotting seems to be drilling large deep holes and filling them with potassium nitrate, which encourages fungus growth, and seems to be safer that the use of other chemicals.
Read on, join in ...
Q. Is copper sulphate
⇦ on
eBay or
Amazon [affil link] a viable tree stump killer? If so, what should the proportions of water to copper sulphate be? Is more than one treatment generally required? What precautions should be taken when mixing or handling? I purchased a pound of copper sulphate at a local hardware store but the clerks in the store at the time of purchase did not know the mixture but said that it was a good means of killing tree stumps.
Thanks,
- Albuquerque, New Mexico
2002
A. It will almost certainly kill the stump, along with almost anything else nearby. copper carbonate ⇦ on eBay or Amazon [affil link] is used as Bordeaux mix for treating grapevines that have mildew on them. Please, please, please do not start dumping chemicals onto the soil, it will not do anyone any good. If you want to remove a stump, either dig it out or get some proper stump remover.
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
A. I have heard that you can kill a tree stump by driving a copper nail into it...no chemicals are put into the soil.
Cheryll Guertin- La Verne, California
A. Hi Cheryll,
In theory, and with enough nails and a small stump, this can perhaps work. But in practice, especially on larger stumps, it is very unreliable because trees can handle a limited amount of copper, and not an awful lot of copper will dissolve and be absorbed.
Although it's something you can probably safely do yourself, it's a mix of myth and reality with the balance probably in the myth direction. Although nothing is safe if you don't know what you're doing, I think a home gardener can probably learn enough about potassium nitrate fairly quickly and apply the method [described below by Charles G.] safely ... but a mask, chemical gloves, and eye protection are always the minimum.
Luck & Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. I have a large stump from tree that is in my back yard, 46" across. There is no access to the stump with a stump grinder. what kind of chemical can I pour into the stump if large holes are drilled into it.
James Hooper- seminole Florida
2006
A. Drill holes in top of stump and fill holes with potassium nitrite / KNO3 ⇦ on eBay or Amazon [affil link] . Pour hot water in holes, and then after it dries out, pour fuel oil in holes and light on fire with a propane torch.
charles gibson- NEW BERLIN, Wisconsin
August 27, 2008
!! Thanks, Charles. KNO3 is actually potassium nitrate, not potassium nitrite though. Readers should read a Safety Data Sheet before using this chemical, and should certainly wear a mask, goggles, and goggles as inhaling the dust is bad for you, and chemical burns are possible.
Readers should also know that fuel oil spills can contaminate the land for several decades, and that this combination is close to a bomb-making recipe; when Charles says "after it dries out" he doesn't mean the potassium nitrate, he means the stump. Be sure the KNO3 is long gone before considering pouring a fuel into those holes. I would suggest checking with the local fire department before trying to burn a stump.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
A. I have had success with copper sulphate by drilling holes in the top of the stump and then packing the holes with copper sulphate use a large drill bit 7/8 to 1 inch, two to three inches deep. Pack the holes with copper sulphate tight enough to prevent it from blowing out with the wind but not so tight it will not easily absorb water. Water the sump regularly don't water so much that the water runs over the stump just sprinkle. The copper sulphate will also kill the lawn and any other plants around. Cover the stump with a plastic garbage can lid and weight it down metal will corrode badly with copper sulphate, tarp or ply wood plastic is best. This prevents pets and animals from contacting the copper sulphate take other precautions with children or don't use copper sulphate at all, remove the cover when watering the lawn or when it rains to help water in the copper sulphate. Do his until the copper sulphate is gone. This will kill the stump and roots and any other trees that have suckered off of the one cut down so do no use this method if this is a possibility. copper sulphate will as so speed up the rotting of the stump.
Good luck and wear rubber gloves
⇦ on
eBay or
Amazon [affil link] gloves and eye protection (goggles
⇦ on
eBay or
Amazon [affil link] ).
- Cove, Oregon
July 16, 2009
Q. Many old overgrown melaleucas have been taken down from behind garages where I live, due to their roots causing plumbing and other utility problems. The stump cannot be stump ground due to utility areas under these stumps ... can we use muriatic acid or ?? safely on the stumps to rot them?
Suzane ColeVillage Grove Townhouse Association - Corona, California USA
February 17, 2019
A. Hi Suzane,
Melaleucas are a very hearty invasive species, so I doubt that it will be truly practical to just drill holes in the stumps and fill them with potassium nitrate as described above, but you could try it on a couple.
Unfortunately I think you'll find that the biocide regimens needed to control melaleucas are for professionals rather than experimenters.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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