Question
OK, we have two large dogs and live on Buckston Clay with no top soil.
We have no lawn. I would like to section off half of my small yard and put
down
some nice smooth river rock with a bit of mulch and a small patio around.
Would
this hurt my large maple and small evergreens, and are there some rocks that
are
搒moother?than others? Any suggestions or advise would be great. Short of
損aving?I'm at a stand still.

Answer
Rock and mulch should not affect any trees unless you dog out the area before applying it. However a patio could hurt a tree if you cover an area of critical root zone. The Critical root zone is usually surrounding the tree trunk and goes out from the tree trunk a distance in feet equal to the diameter of the tree in inches at four feet off the ground. In other words. If your tree is 10" around at chest height then you have a critical root zone that has a radius of ten feet. So any patio should be at least ten feet off the trunk if possible. Covering a little area may not kill the tree though so this is a "loose" requirement.

Pea gravel is good for dogs but you will need 3 to 4 inches of it.

As for rocks with smooth finish, any river gravel or tumbled gravel is rounded. You'll need to go to your local earth product provider to see what types they have. Rock types available vary greatly by locale.

Best of Luck
Sean J Murphy, LA,ISA, LEED AP
Please check out my blogs and articles on landscape topics like this on my websites.
http://www.seanjmurphy.com
http://amenityarchitects.com