Tree Roots from dead tree

[Riickk]

Original owners of my 1962 house planted a tree *directly* over sewer line where it transitions from my 4" cast iron to County's clay pipe.

That tree was taken down 3 months ago. Will the roots that are partially blocking that waste line rot out by themselves, or should I have plumber cut them out?

 

[Twowaxhack]

I might would wait and see…….

 

[breplum]

From my experience, having them cut out would give best peace of mind.
Roots really do not tend to rot.

 

[Bird Doo Head]

An arborist taught me that small roots will continue to grow, sometimes for years, after the tree is cut down.
I'd do like Breplum suggested and get pro to run a cutter run through.

While the cuts are fresh, but at a time when little water will be used for a few hours, flush about 1/4 - 1/2 cup of copper sulfate down the drain. It'll cling to the freshly cut roots and make them die back. I'd repeat the copper sulfate every week for a month, then every 6 weeks until winter. You could, in spring, have the line snaked to find out the status.

On line, the crystals are much less expensive than in hardware stores or home centers. You'll also get 100% copper sulfate with no fillers. Mindy Materials is usually a well priced source.

Years ago, digging up a line that was treated with copper sulfate for 6 weeks showed that the roots died back more than 2 feet from the pipe.

I'm not a pro, but have had more than one house with clay-versus-root problems and it happened to the plumbers at work often. Take this advice as secondary to what the plumbers tell you here. Paul

 

[Twowaxhack]

I agree with having them cut out if a blockage would be a doomsday scenario. If it’s just a minor inconvenience then I’d wait and see if I had trouble.

I’ve never seen a dead tree that the roots didn’t eventually rot just like the stump. Keyword is “ dead “. If there’s activity above ground ( sprouting from the stump) then the tree isn’t dead.

I’d be more concerned about how big the crack, gap, hole, etc, is where the roots are intruding and if I was going to have sink holes Where the surface dirt washed into the pipe from rain after all that organic matter rots away and or is cut out with a jetter or cable.

I might would use copper sulfate ( if it’s legal in your state) and kill the stump or grind the stump out.

 

[Bird Doo Head]

Pounding a copper pipe or rod into the center of the stump will kill the stump and the roots, but it will take time. A copper-clad steel grounding bar might work. (The copper cladding in thin.)

Copper sulfate in a hole in the trunk is often suggested, but insects go in and are killed. This includes beneficial ones, such as pollinators.

 

[Riickk]

That tree came down in late February, and was ground down on the same day. Nothing growing, at least above grade. I have a sack of copper sulfate, and can run that down the sewer line as a foam; whether it will speed rotting, can't say; It doesn't seem to speed rotting of a different stump, where I've drilled holes and poured crystals inside.

As far as a sink hole developing where the roots entered, the cast iron pipe ends just under the 3-ft grass margin between the street asphalt and the sidewalk -or- right under the sidewalk. If a problem develops, it will probably be under someone else's watch, this house too big for me. Then again, is there anything I could do to prevent a problem? Have a few feet of 3-inch, Schedule 40 ABS / PVC pipe inserted into the clay pipe and cast iron, overlapping where they meet?

 

[Bird Doo Head]

"whether it will speed rotting, can't say; It doesn't seem to speed rotting of a different stump, where I've drilled holes and poured crystals inside."
It won't help with rotting other than by killing the root or plant. Then nature takes over.

Because of the resins, roots take a very long time to decompose which is why many composting facilities won't accept them.

If you plan to dig & put a PVC sleeve, maybe you'd prefer this plan:
There are companies who line underground pipes by cleaning, then spraying in a cure-in-place material. It will jump gaps where pipes spread apart and where roots poked holes. It even works if water is trickling in the pipe.

Some cure-in-place linings are epoxy, some are simple resins & some are fiberglass. I've cure-in-place in many times on underground walk-in electrical ducts & vaults, transmission conduits and even pipes.
Many of my neighbors have had their clay tile sewers lined with success. Check with your city. They may have a recommended contractor that they use.

 

[Riickk]

Thanks for the info.
Will probably just have someone run a cutter through from street side. Manhole in the street is some 25 feet from my where my pipe hits the sewer

 

[Bird Doo Head]

No, the roots that are partially blocking the waste line will not rot out by themselves.

If you take a root and stick the end in a bucket of water, it'll start to grow a new tree- and the root will grow more shoots.

A boss of mine took a reciprocating saw & a very long blade and cut a circle 2 feet away all the way around the stump of a pine tree that was cut down. The next spring, he had a circle of little pine trees growing.

 

[BlueSkyHigh]

If you take a root and stick the end in a bucket of water, it'll start to grow a new tree- and the root will grow more shoots.

A boss of mine took a reciprocating saw & a very long blade and cut a circle 2 feet away all the way around the stump of a pine tree that was cut down. The next spring, he had a circle of little pine trees growing.

Life will not be denied. Life will find a way.

 

[RS]

I had a similar problem last year with a live tree, I got some copper sulfate and treated the area around a drain tile, time will tell. Many years ago I used copper sulfate to clean the weeds out of a backwaters, it works!