Question
I have a cement patio just (3) feet from a King Crimpson mature maple.   If I remove the cement patio, will it damage the maple. Could the tree fall on my house that is just 20 feet from this tree?  I would like to replace the patio.  What type of patio would be least destructive to the tree?  Do you recommend removing the mature tree for safety reasons?  I love the tree....so worried about the destrution of my cement slap patio and the impact the replacement patio will have on the tree.

I can not replace with a deck...not enough pitch to the yard.   Thank you for your time and help in th is matter.

Answer
The problem will be removing the cement without damaging the root system of the tree. Machinery driven over the roots will compact the soil and damage the roots. It can be done but by hand would be the best method. Do not dig any deeper than the cement that is there now. You did not say how thick the cement was but the new patio IF you use cement should not extent any further into the soil. No scraping with machines-this can damage the roots.

To what extent will depend on the amount of soil that is moved when grading and the percent of the root system that is damaged. The tree can do fine with as much as 25 percent of the root system damaged without much problem to the foliage. When roots are damaged he tree can not produce enough food and water to support the total foliage and some foliage will die back. The roots are within the first two feet of the soil surface and extend out about 1 1/2 times the width of the foliage. You can figure the percent damage by out lining the roots width and deleting area that will be damaged. IF this is more than 30 percent the tree will exhibit a good bit of foliage damage and die back.


Pavers can work as long as you do not add more than a couple of inches of sand over the roots. Cement will with any digging will damage the trees root system and in turn the foliage will dieback. Also the cement can change the pH of the soil and cause foliage damage. I would think about a wooden patio. Place the runners on pavers and level it before making the patio. Use treated lumber and leave small gaps between the boards for drainage so the root will get the rain fall. Do not come any closer than about 3 feet from the trunk this will leave space for growth and not damage the root collar. Also cement and pavers will be lifted by the roots over time. The wooden should not have this problem. Make the wooden  patio as close to the ground as you can treated 2X4 laid flat will give only 2 inch step up.

IF you dig 3-5 inches of soil from around the tree you will damage the root system. IF more than 25 % of the root area is damaged you will see dieback of tree foliage and limbs.

I would not remove the tree--the shade will be good when sitting on the patio. With out seeing the area now this is about as good as I can get. I hope this helps.