Root pruning. How is it done?

[argueta]

A customer has a bald cypress that is mature and has roots going through his lawn. Is it dumb to grind the roots below ground level? He wants them out so wont be running them over with the lawn mower. Thanks for any input

 

[mndlawn]

Your MUCH better off leveling off the lawn with topsoil than messing with the root system.

 

[pdqdl]

It is damaging to the tree and can cause death or "blow over" in heavy winds. This is a very risky plan, and there are better alternatives.

1. Exposed roots are pretty easy to cover with more dirt. Bring in some pulverized topsoil and sift about 1/2" deep layer anywhere the roots are a problem. The existing grass will grow up through the thin layer of topsoil.

Wait two months...

Add more topsoil, providing the grass has grown thick and health through the exposed roots. Add no more than 2" per year, so that the tree can grow fine roots into the new soil also.

Continue this plan until you have a great lawn with no exposed roots. If you hurry, you will choke out the lawn and you can suffocate the tree as well.

2. Mulch! Many arborists don't care one whit about the lawn, and will recommend huge mulch rings around the tree to eliminate competition from the lawn. I personally don't believe that the lawn is significant competition, but a nice mulch ring improves the soil culture around the tree, it provides measurable benefits over the bare dirt often found underneath a tree, and it looks good as well. No mowing required, unless you allow weeds to flourish.

Weeds run rampant? You can still mow them, and the roots won't be in the way, either!

3. Landscape! Once you have a nice big mulch area beneath the tree, investigate other landscape plants that flourish in the shade and root zone of a tree. Plant what you like, and have fun with it. Do a little at time, and see if the property doesn't begin to look fabulous, with an improved lawn too.

 

[argueta]

This is how it is, the cypress is in the corner of the lawn. There is stone landscape around it and the roots are exposed in the lawn passing the stone. So would the only alternative be to use topsoil?

 

[pdqdl]

No.

You can cut off all the roots, and take the risk of tree failure.

You can cut a few roots at a time, taking MANY years to reduce the problem. If it took 20 years for the tree to grow a root, it will probably take 20 years to grow it's replacement.

You can cut the tree down, and eliminate the problem.

You can rent or hire a stump grinder to shave the exposed roots down to the ground level. This method is just a little bit better than whacking them entirely.

Why fight it? Adding a little topsoil every now and then is the cheapest and easiest solution, and there is almost no risk of failure.

 

[argueta]

This is it. Shaving the roots to ground level was word I was looking for. We have a stump grinder. The roots are not foot long or huge exposed roots. They are scattered throughout the yard and are like 6x6 inches of roots exposed here and there. I was thinking of shaving them to ground level but don't want to stress the tree

 

[kennertree]

What's wrong with mulch? If you dont want to harm the tree leave the roots alone. Grass is so over rated.

 

[argueta]

What's wrong with mulch? If you dont want to harm the tree leave the roots alone. Grass is so over rated.

The roots that are exposed are throughout the lawn, so mulch wouldn't work to cover it. On the other hand, if they were in the flowerbed that is surrounded by stone, it would work.

 

[kennertree]

Post some pics, how far are the roots coming out past the dripline?

 

[argueta]

I don't have any pics with me but I would say about 10 feet past the drip line

 

[kennertree]

I would do as little as possible, I wouldn't go the stumpgrinder route, try to make nice clean cuts on those roots.

 

[pdqdl]

If you are out past the dripline, you will probably be fine to grind out some roots here and there. A bald cypress is tall and narrow, but they are exceptionally hardy, too. They also have a native habit of sending roots up to the surface, particularly when they are submerged.

Don't go crazy grinding surface roots and you will probably be fine. Don't grind out any structural roots unless you are planning on gambling with the health of the tree.

 

[treeseer]

6x6 wha??

move the stone wall out. if you need to clip little roots a sharp loppers is better than shaving.

 

[danieltree]

Bald cypress is the worst yard tree for this very reason. I have seen the roots come up in the center of a guys house 80 foot away. I have ground them down many times with no adverse affect to the tree. They just pop back up elsewhere. One alternative is to incorporate them into the landscape. I had one customer that had me remove the sod and lay gravel down with the roots sticking up it looked great. For those that are not familiar with bald cypress, these roots sticking up can grow as high as a foot in a couple of years. I have also seen them continue to grow after the tree was removed.​

 

[EdenT]

They also have a native habit of sending roots up to the surface, particularly when they are submerged

If the tree is sending up roots, it is most likely trying to get oxygen, it probably indicates either over watering or a lack of soil aeration, or maybe just an impenetrable substrate just below the surface in those areas. Whats the lawn like in the areas where the roots are exposed?

 

[Golf]

If the tree is sending up roots, it is most likely trying to get oxygen, it probably indicates either over watering or a lack of soil aeration, or maybe just an impenetrable substrate just below the surface in those areas. Whats the lawn like in the areas where the roots are exposed?

I agree and also short frequent watering. Very common of golf courses.

 

[rarefish383]

If the tree is sending up roots, it is most likely trying to get oxygen, it probably indicates either over watering or a lack of soil aeration, or maybe just an impenetrable substrate just below the surface in those areas. Whats the lawn like in the areas where the roots are exposed?

I'm gonna have to research this some. I know many species have a tendancy to produce surface roots. Many Maples, Hybrid Poplars, even my Hybrid Honey Locust is starting to through surface roots. I live on top of shale and the ground is bone dry hours after rain. The soil is not compacted and aeration should be excellent. So, why are my trees throughing surface roots. I think it's more in the nature of the species than a need for oxygen, Joe.

 

[EdenT]

I'm gonna have to research this some. I know many species have a tendancy to produce surface roots. Many Maples, Hybrid Poplars, even my Hybrid Honey Locust is starting to through surface roots. I live on top of shale and the ground is bone dry hours after rain. The soil is not compacted and aeration should be excellent. So, why are my trees throughing surface roots. I think it's more in the nature of the species than a need for oxygen, Joe.

Cheers Joe, I would certainly like to see some more research on this. It does occur to me that it could be species specific but it still makes me think that the species has a greater oxygen requirement. The problem I have is that roots are not photosynthetic, don't have stomata or guard cells to prevent dessication etc. It does not benefit the organism to have aerial roots in any but anaerobic situations. Also people are notoriously bad at empathizing with botanic requirements and do crazy stuff like watering at nightfall when the plant actually needs it's oxygen.

WRT your honey locust don't forget that the root surface usually needs to be moist (but not wet) for gas exchange to take place. Emergent roots with fine root hairs are good condensers for air laden with moisture.

 

[danieltree]

These projections he is talking about are called knees. If you cut it off it has no affect on the tree. Here in Louisiana they have been destroying lawnmowers for years. From what I have read no body knows why the tree grows these things, they first thought that it was to deal with wet soil to get oxygen but discovered that was not the case. The knee has the same bark on it just like the tree. I would not grind next to the tree but have had no problems grinding to just below the surface outside the drip line. When I was first asked to do this I balked but talked to a guy that had been grinding in this area for years and he said that it seems to have never caused any problems to the trees he has ground. I really see no difference between grinding bellow ground level once and cutting it every two weeks with your lawnmower.​

 

[EdenT]

V interesting DT. Is this species specific. and also forgive my lack of geography but isn't Louisiana one giant river delta - indicating silty/clay soils etc.

Also I have problems with the whole 'improving the appearance of your lawn with a stump grinder' theorem. Even when I am gentle and precise it looks as though the lawn has been gang raped by a flock of panzers. I loved your earlier idea of turning them into a landscape feature. I think that would look fantastic. I'll give you some rep as soon as....