Using Caustic Soda to Help Remove Tree Stump

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AngieR

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We're almost done chopping down a tree stump in our backyard; it's about 6 inches below ground level and we plan on leaving the rest to decompose. The roots have all been severed at the base and there hasn't been any regrowth sprouting up again. I've read that a high nitrogen fertilizer can be used to help decompose the remaining stump by drilling holes into the stump and filling them with the fertilizer, which feeds the fungus that will help the stump decompose. Another method i've read about calls for covering the tree with caustic soda. I believe caustic soda can react violently when combined with water, and can be quite nasty to use. Since the stump is close to a flower bed which does get watered I would assume that the stump would have to be covered with plastic for a time. Does anyone have any personal experience with either methods, or even any other suggestions?
 
Caustic soda goes by many names. Sodium hydroxide, NaOH, and oven cleaner are just a few of them, and no, sodium hydroxide doesn't react violently when it comes into contact with water. If it did, it would be a danger to people using oven cleaner and water at the same time.

Generally tree roots only grow to a depth of 2 to 3 feet or so into the ground. There may be a longer tap root directly under the trunk, but normally there's just a root ball that isn't much larger than the diameter of the tree trunk.

Your best bet would be to excavate around the tree trunk and cut the roots as you encounter them with a reciprocating saw, and then pry the entire root ball out of the ground.

However, if that's not feasible, then I'd say the way to accellerate the rotting of the tree trunk would be to cut kerfs or drill holes into the tree trunk to increase the contact area between the ground and the wood, cover with top soil, and keep the area damp by occasionally watering it. The fungii that feed on wood are ubiquitous in soil, and the only thing they require is that the wood be wet enough to rot and there be sufficient oxygen in the ground for those fungii to survive. So, covering the wood with mud and periodically watering that mud to keep the ground (and wood under it) wet will promote the wood rot fungus to grow and multiply quickly.

If you're curious to see whether caustic soda will do anything, just put some oven cleaner on the stump overnight to see what it does. Caustic soda is typically a solid. You can make caustic soda by leaving oven cleaner out in a plate overnight so that the water evaporates out of it. The white salts left behind will be caustic soda.
 
hey Nestor, we've dug down a little more than a foot arund the trunk and any roots we've come across have been cut. There were also roots that had come to the surface of the yard, which we dug up and cut out as much as we could. There's another 6 inches of trunk we can still chop away at with what tools we have (mattock, saw, sledgehammer, wedge, axe) My husband has drilled down from the top of the trunk with a 8" drill bit and has pulled up some dirt, which really excited us :) Pulling the root ball out completely will probably not be something we can do on our own, but I like the idea of letting the rest of the trunk decompose. Thanks for the reply and the information. Now we just need the rain to let up so we can get back to work on it.
Cheers
 
yeah, the simple solution is just to cover what is left wit dirt and plant some grass or flowers. The issues could be
1) the area will sink some (over years) as the stump decomposes. Just add more dirt.
2) the area could be water starved and not easily support grass growth. I have seen this were there are large roots or rocks just below the surface.

The best solution would be to not worry about it and go have a picnic!
 
Do people still go on picnics? You mean with picnic baskets and plaid tablecloths, ants and a frisbee?


I did not know that.;)

Hmm, good point. I think its been 20 years since I went on one. (part of the courting process ya know)

Maybe have a beer? Go to the pool? I know, catch up on old episodes of The Handyguys Podcast!
 
forget the plaid tablecloth the ants and the frisbee, how does a picnic with beer sound?
as for the original question, we're planning to plant a smaller tree in the same spot next year, so we're trying to eliminate as much of the root system as we can on our own. we have a townhouse with limited backyard space, so a pickup truck and chain is not an option.
 
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