FragileWarrior wrote in news:f3mrvn
:

"Bob F" wrote in
:

My neighbor, who rents, recently raised the ground level around two
poplar trees near my side of the lot. I have always understood that
doing this will cause the bark to rot, thereby eventually killing the
tree. I talked to the landlord, who said "his sources" say it is no
problem. I am worried because the prevailing winter storm winds would
tend to drop the tree on my house if it falls. The ground level now is
about 1 foot higher on one tree and 2 feet higher on the other than
the origional level. Am I worrying needlessly?

Bob




No, you're worrying correctly.



Sorry, I should have expanded that answer.

Check out:
http://forums.gardenweb.com/forums/l...016207308.html

and:
http://www.lsuagcenter.com/en/enviro...restry/Protect
ing+Shade+Trees+Around+Your+New+Home.htm

which contains this bit:
"Grade Changes
Trees depend on the feeder roots in the upper 6 to 12 inches of soil for
air, water and minerals. Most feeder roots are in an area under the tree
crown in open-grown trees. If you extend perpendicular lines from the
widest portions of the tree crown to the ground and connect these points,
you’ll enclose an area that includes most of the root system.

Because most of the roots are in the upper 6 to 12 inches of soil,
lowering the grade and consequently removing those roots under a tree
crown can be harmful. Generally, protection is achieved by terracing the
grade to keep soil disturbance as far away as possible from the trunk. If
space is available, the tree may be unharmed if you let it remain on a
gently sloping mound. Another way to protect trees from root damage
caused by lowering the grade is to build a retaining wall between them
and the lower grade. This is an effective way to save trees if the grade
difference is less than 2 feet. Don’t forget to leave drain holes in the
wall.

__________________________________________________ ____________________
On the other hand, if you raise the grade by adding soil, the tree may
slowly decline in vigor or die because of difficulty in obtaining
essential air, water and nutrients. It’s often possible to add up to 2
inches of a light sandy-loamy soil without killing your trees. A tree
well with perforated drainage tiles is necessary to allow drainage if you
plan deeper fills. Contact a professional consulting arborist with help
with lowering or raising the grade around trees during construction.


Trees with damaged or buried roots often do not die immediately; in fact,
they may live several years before declining. Once damage becomes
evident, it is probably too late to correct the problem."
__________________________________________________ ____________________