Grinding Roots....Safe or not?

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Longbeard

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Hello everyone, I am in the stump grinding business, and having a small self propelled machine, (Vermeer SC252), I often get hired to grind roots that have become a trip hazard, etc. It's usually an Oak, Pine, or a Magnolia.

Sometimes they want me to just grind the roots down level with the ground, other times the roots will be completely above ground, and grinding them down means cutting them out altogether. It usually comes down to what the customer wants.

I obviously don't want to kill a tree, by grinding too much of it's root system. I doubt a good evaluation could be made without seeing each individual situation first hand, but I was wondering if there was a "Rule of Thumb" that could be applied here?

Thanks!
 
I don't think you are understanding me.

I have seen myself...many...many trees....that over the years have had protruding roots ground down. I know one man who has been grinding stumps for over twenty years, and has on many occasions done this. I know of one particular property that has us come in every few years to do just that. Some of the trees have had roots ground down several times. And the trees have withstood this for a lot of years. So it all is not black and white...as you suggest. But thank you for your opinion.

And thanks for the "warm" welcome.
 
Easier and better money in correcting the soil problems that lead to surface roots in the first place, than grinding them all out.
Root pruning is not unheard of, but is relatively new, imo.
-Ralph
 
begleytree said:
Easier and better money in correcting the soil problems that lead to surface roots in the first place, than grinding them all out.
Root pruning is not unheard of, but is relatively new, imo.
-Ralph

It's relatively common in this area.

I agree with both of you that it's not a great idea to grind down the roots. That's a no brainer. However, homeowners don't tend to see it that way, they want a quick easy fix. Especially when it's in the middle of manicured lawn that they have a lot of time and money invested in.

As I said, it's been done to hundreds of trees in this area, and to my knowledge, none of them have died. Maybe some did, but I don't know about it.

My question was basically...where to draw the line.
 
Just a spur wearing tree topping hack so it will come as no suprise that I don't see anything wrong with it as long as you don't get too carried away. Many trees have there roots mowed year after year by people to lazy to raise the blade deck. Those trees are still there years later. What about when guys bust the roots (wrist, arm size) with an excavator to widen the road, or lay pipe? Seen it many times, usually they live, even after getting just hacked. Begley is right idealy, but if the root is causing great concern it has to get shaved.
 
clearance said:
Just a spur wearing tree topping hack so it will come as no suprise that I don't see anything wrong with it as long as you don't get too carried away. Many trees have there roots mowed year after year by people to lazy to raise the blade deck. Those trees are still there years later. What about when guys bust the roots (wrist, arm size) with an excavator to widen the road, or lay pipe? Seen it many times, usually they live, even after getting just hacked. Begley is right idealy, but if the root is causing great concern it has to get shaved.

That's exactly my point. And after they get tired of sharpening /replacing mower blades...they call a stump grinder. With all that being said...I now wonder why I even questioned it in the first place.:sucks:


"spur wearing tree topping hack"...sound like a lot of my buddies! lol
 
See "Trees and Turf" in the link below. Your question is good and deserves a careful answer, somewhere in between Don't YOu Dare and Go Ahead It Don't Matter.

Pruning roots is like pruning branches. Not too close to the trunk, not too large a diameter, leave clean ends not ragged ones. At some point the trees need a mulched area; 1x the dameter away from the trunk is a minimal guideline, adjusted for species and crown form.
 
I won't personally grind any roots off, and I'd be aware that if my company performed this type of work that they'd be opening themselves up to a potential liability. That said, the first company I worked for had a client who insisted on removing surface roots. After trying for years to get him to just mulch the area, we came to this agreement: A small mulched area and removal of one surface root per year from the lawn area ( clean cut on the end, properly done). This isn't the immediate gratification most clients will be seeking when they call, but may be an opportunity to educate and form a lasting relationship with a client. He was sure to call for work every year to get another root taken out - far as I know he is still a client of that company.

You asked for a rule of thumb, so I looked up one I wrote down a few years back - borrowed from a lecture by Ed Hayes, University of Minnesota. A 2 inch root can hold the weight of 2 elephants, but a 4 inch root can hold the weight of 10 elephants. That's a bunch of support you are potentially removing from a tree, so be carefull how much you remove. Good luck.
 
Longbeard, If you come here to ask a question, and get mad that the answers you receive aren't what you wanted to hear, you're probably on the wrong forum.
I don't care how long you or anyone else you know has done it. I don't care how long you or anyone else has gotten away with it. You are setting yourself up for a costly lawsuit when one of your stumpground trees falls over and kills someone, or destroys property, and you will lose. There's right and wrong ways to prune roots. Just randomly grinding them up isn't the right way. What you're doing isn't root pruning, it's root removal.
-Ralph
 
The rule of thumb I sometimes use is to stay at least five times the diameter of the tree (diameter at breast height) away from the trunk when cutting a root. So with a 24" tree, for example, you need to stay 10 feet away.
The thinking behind this is that a tree's buttress roots have what is known as a zone of rapid taper, and large injuries to this area will have a hard time compartmentalizing. This means decay can enter and advance faster than the tree can wall it off. Eventually the decay can move up the root and effect he whole base of the tree.
This does not mean you can cut a 10 foot wide trench around a 24" tree, it just means that if a root needs to be cut, 5 times DBH is the absolute closest you should be. The 5 times DBH should get you past that zone of rapid taper.
How the tree will respond to cutting roots will mostly depend on the age of the tree (the younger the better), the overall health and vigor of the tree, and the percentage of the root system you are cutting.
If you cut one large root, you can easily be removing 20% of the trees roots!
If you do do some root pruning, it may be a good time to sell an application of Cambistat, a growth regulator that will help re-grow the trees roots. See Rainbow Tree Care's flashing banner at the top of the page for more details.
 
TreeCo said:
It's apparent you knew the response you would get with your question and why wouldn't you.........any knucklehead knows better than to grind off a trees roots with a stump grinder!
Dan

If the operator was to run the grinder very gently, the grinder was sharp, and the root was supported by the soil, I would think a stump grinder would make good cuts.
 
We are on our third year of using Cambistat and I have to say it does what it says. There are some issues with dose but other than that, it's better than doing nothing.
I will defer to your experience with grinding, as I'm a climber, not a stump grinder. I do agree that an above ground root would be roughly snapped off, but it seems when you get to the point where the root is completely surrounded by soil the grinder could do a reasonably nice cut.
It may be better to expose the root back to a node (that's for you Guy) and make a proper pruning cut with a sharp handsaw, but the value of that would depend on how big the root was and how far from the tree it was.
Do roots even have nodes?
 
begleytree said:
Longbeard, If you come here to ask a question, and get mad that the answers you receive aren't what you wanted to hear, you're probably on the wrong forum.
I don't care how long you or anyone else you know has done it. I don't care how long you or anyone else has gotten away with it. You are setting yourself up for a costly lawsuit when one of your stumpground trees falls over and kills someone, or destroys property, and you will lose. There's right and wrong ways to prune roots. Just randomly grinding them up isn't the right way. What you're doing isn't root pruning, it's root removal.
-Ralph

First of all begleytree...your posts are the only ones in this thread that sound "mad" to me. Maybe it's because everyone doesn't agree with you?

Second..."Just randomly grinding them up isn't the right way."...where did you get that from? I'm talking about shaving down the tops of roots to eliminate a trip hazard, not grinding all the roots around a tree. As I said....you are not understanding me.
 
TreeCo said:
You did ask a good question. You got good answers too. Has anything anybody said influenced your opinion?

Dan

Yes, there have been a lot of good comments posted about this, and a some of them were exactly what I was looking for. Others were completely disregarded for other reasons.

Special thanks to clearance, treeseer, treeman45246, Mike Maas. I appreciate your comments, and more importantly your attitude about the whole thing. I didn't come here to start an argument, only to seek advice, and learn.
 
Longbeard, no one is 'mad ' at you. the advice was free, take it for what you have in it. The only reason I remotely care is because you will make the funny papers about killing a family, the paper will call you a tree care professional, and thats another black eye for out industry.
You've only gotten 2 straight answers to this topic, both told you that you were doing wrong. If you don't care, I sure don't. We have members in your area, and they'll post a copy of the paper when you make it.
If you already have all the answers, why come here and ask the question?
-Ralph
 
TreeCo said:
Some of us understand you. You are doing serious damage to the trees you are grinding.

Some of the arborist responding to this thread have been a little wishy washy about the damage you are doing. I think maybe they didn't fully understand what you were asking.

Dan


I am confident that you don't fully understand what I'm asking.

I am NOT talking about grinding out roots completely, we've all seen how roots that are near or at the surface can get a "knot" protruding above ground. And when they do, they get shaved down with lawn mowers regularly. I am talking about merely getting the problem areas lowered out of harms way. You seem to think that I grind roots like this, in the same manner that I would grind a stump. That is incorrect. I would never grind any more of a root than was necessary to satisfy the customer. But at any rate, I thank for your input just the same.

Maybe in the future I can post a few before and after pictures, and that should clear up any doubt as to what I mean. My camera was a victim of an "unfortunate accident", :bang: so it will be a little while before I can replace it.
 
begleytree said:
Longbeard, no one is 'mad ' at you. the advice was free, take it for what you have in it. The only reason I remotely care is because you will make the funny papers about killing a family, the paper will call you a tree care professional, and thats another black eye for out industry.
You've only gotten 2 straight answers to this topic, both told you that you were doing wrong. If you don't care, I sure don't. We have members in your area, and they'll post a copy of the paper when you make it.
If you already have all the answers, why come here and ask the question?
-Ralph

Duly noted.

Well, since you feel so strongly about this, surely there must be some cases where someone ground a few roots off a tree, and the results are just as you say? Otherwise why would you say it, right? So...do you have any links to stories like this that I could read? Not just someones opinion, actual cases where this happened? I know that a tree can be killed by excessive root grinding, obviously this can happen, that is not in question. I'd be very interested in reading them. Thanks again.
 
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begleytree said:
You've only gotten 2 straight answers to this topic, both told you that you were doing wrong.
-Ralph
I'm curious which two answers you feel were straight, because frankly, your responses sounded rude and totally lacking any content. To blindly say a stumper should never be used to cut roots, presents the problem of removing a stump in any area where there are other trees.
If the root is small enough and far enough from the tree, I don't see it as any worse than removing a branch, or a branch snapping off in a storm.
The idea of just grinding half way through the root sounds like a bad idea. It may be a better idea to just remove it, both because by half grinding it, it will be shaped to hold water, and the tree will quickly start repairing the wound which will send new wood back into the lawn, requiring repeated wounding.
I also disagree with Guys 1XDBH, that is too close to safely remove a root. I have repaetedly heard 5XDBH by experts, and personal observation has shown closer than that to often be a problem.
 
Mike, I mis-counted, make it 3, I was talking about dans, treemans, and yours. Please show me where I was rude by saying it's better to fix the cause, than to treat the effect? Shortly after that I was told that I don't understand english, so I pointed out that I know exactly what he was saying, that it's still wrong, and pointed out the possible legal ramifications from his actions. to which he resoponded I was mad. Unlikely, to be mad I'd have to care.
Please tell me what happens when you grind the top off a living root, then cover it with soil. As far as I know, it either decays (bad) or grows callous tissue over the stump ground area, and becomes exposed again.(time for round 2 stumping, I guess.)
I'm just saying that there are better ways to fix his customers problems without compromising the safety and stability of the tree. All this because they are 1. given poor information by the grinder operator in order to make a buck, or because he knows of no better way. or 2. because they are too lazy to pick up their feet when they walk, and 3. too blind to see the roots and run them over with the mower, and have to spend $10 on a new blade.
Roots hold trees upright, what happens when you remove them?
-Ralph
 
LB the trees and their owners would be a lot better off if the areas with protruding roots were mulched. If you want to sell a more responsible service, carry some bags of mulch around with you and apply it where roots should not be disturbed.
Shaving the tops makes a big wound, open to all kinds of infection and decay. Roots generally do wall off decay better than branches, but best to use the stump grinder for grinding stumps.
 
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