I had a ~25 yr old doug fir cut down a few years ago and I'm finally going to do something about the stump. My water main is very close to the tree, so I wanted to avoid grinding. I was going to go down the route of chemically killing it (e.g. copper sulfate crystals in drilled holes) and digging it out, but I just realized that my neighbors similarly aged vine maple is just on the opposite side of the fence, maybe ~6 feet between stumps.

I suspect there might be some risk in affecting the vine maple. Last thing I want to do is kill my neighbors tree. Thoughts? If that's the case, I'll get a more exact location on my water main and if it's still too close to comfort I'll resort to a more manual approach to cut/dig it out.

 

Your location will determine how deeply the water line is buried. You can check code for your area but most are at least 12" deep.

Grinding is the quickest and one of the better ways to get rid of the stump. They can control the depth of the grinding and stay well above your water line. Normally I'd also suggest an excavator to dig out the stump but that should be avoided because of your water line nearby.

Copper sulfate can be put down the drain to kill tree roots growing into sewer lines. It is NOT used to promote the rotting of a tree trunk. Also, do not spill or pour it on the ground around the tree where it could get watered into the soil. That could kill your neighbor's tree

Tree stump removers use an oxidizer like potassium nitrate. Follow the directions and wait... Since you are removing a dead stump any chemical you apply to the stump doesn't travel far through the dead wood. The chemical doesn't get transported through dead roots so there is very little (no) risk to your neighbors tree.

 

Thanks for the reply. My county (WA, King) says 24" minimum for a water line, but not sure what it was back in '91 when the house was built. My meter is close by (other side of the fence, stump is in the corner of the yard) so I can get a good gauge of depth and location, but I'll get locate out here for sure if I grind. I'd prefer to grind.

When searching for chemical methods, I saw mentions of copper sulfate as well as potassium nitrate and epsom salt. One product (Bonide Stump-Out) uses sodium metabisulfate. Seems like people have had good success with copper sulfate, but like you said it could leach the soil and kill anything nearby. Looks like the safer option is to go with a product like Stump-Out.

 

So why are you wanting to add chemicals to a tree that was cut down 2 years ago?

 

I thought the potassium nitrate (or similar) treatment speeds up the decomposition of the stump so it is easier to dig out/remove. Maybe I misunderstood?

 

Yes, many of the stump dissolving chemicals work better on a stump that's been dead for a while. The dry wood/stump allows the chemical to soak in better. You drill holes, pour in the powder then water. The chemical soaks into the wood and breaks down the lignin.

Make sure you buy stump remover and not stump killer (which is usually just glyphosate (RoundUp)). They are different products.

 

Good point. I realized that when searching around. Here's a good page explaining killers vs. removers.
https://homeguides.sfgate.com/stump-...cts-76254.html

The Bonide Stump-Out product is sodium metabisulfate and there is Spectracide Stump Remover which is potassium nitrate, both of which are a remover/decomposing agent. I'll give one of those a try if I go the chemical route.

 

What I always have done, cut the stump down to the ground, build a good size fire right on top, lots of embers, and it will burn down several inches below ground. Just clean up and add some dirt!

Being several years old it will burn easy!