Any arborists in here?
We’re doing some landscaping…namely adding a retaining wall to the front of our house. In doing so, we’re going to end up covering up part of the root zone of our 20′ Maple tree in our front yard. I know you can only cover so much before you potentially damage the tree.
It looks like we’re going to cover about 25% of the root area. Is that acceptable? It appears that this tree’s root zone also extends quite a ways out from it’s canopy drip line, so if we only count the drip line of the canopy, we’re maybe only covering 15% of the area with new soil.
We don’t have too many other options, as the area we are going to be covering is currently a very steep, eroding hill (hence the retaining wall). But we also don’t want to do serious damage to the tree…
Replies
I think it also matters as to how much fill is going to be placed on the root zone... ie - a few inches is no prob for almost any tree. Also, some trees are much more "fragile" than others. I believe that maples tend to have very shallow root systems. If you don't get anything here maybe check at the Taunton gardening forum?
I had an arborist look at some very old Maple trees that were showing fall color in July three years after construction on my home site. Here's a few of the points he made.
You're spending a couple of thousand dollars or more on landscaping? I'd recommend spending fifty dollars more and having a arborist come out to the site and advise you. It would be a shame to loose the tree.
The arborist.com people will give you very definite answers. As already said, it is relatively easy to kill good trees. Like some here, what you will also get there is to hire a certified arborist. As a big DIY, so always phrase my questions such as "a certified arborist last year told me xyz, she moved away, and an arborist with qwerty company told me a slightly different story, etc...."
http://www.arboristsite.com/
Thanks all, will check out the arborist site.The tree it on the edge of the steep slope. The part we're covering is the steep slope side, and will go from nothing to about 2' towards the wall, so it's definitely enough to harm the roots under that area.As much as we'd hate to loose the tree, we're going to loose it evnetually anyways as the hill keeps eroding, so we're inbetween a rock and a hardplace on this one.I agree, getting an actual arborist out is the best option.
There are things you can do to mitigate, providing air to the roots by drilling holes is one of them, mulching, generally improving the root conditions of other parts of the tree, etc. People generally treat their trees pretty harshly so you may have leeway to fix other problems which may help it weather the new injury. Your arborist will know a set of things they do to help out ailing trees in your area.