"Audrey P" wrote in message
...

We live in South West France. normally we get temperatures of up to 34
degrees C in summer, and short periods of minus 9 to 12 degrees C in
winter.
We have had a patio consturcted and have left a one metre diameter hole
for a tree to be planted to give some shade. The patio is laid on one
foot of reinforced concrete, and underneath that there is solid clay,
which in the hole makes water very slow draining. We have been advised
that the tree roots may rise and distort the patio in time. Is this
likely to happen?

If you plant the tree too deep the woody roots will often come up and become
surface roots.

http://home.ccil.org/~treeman/ppb1.html

http://home.ccil.org/~treeman/ppb2.html

ALSO SEE THE FOLLOWING FOR PLANTING
http://home.ccil.org/~treeman/sub1.html

If so, what type of shrub or small tree would thrive
in these conditions without endangering the patio?

How big is your patio? Do you have room to make a big pot? I can give some
suggestions for a big pot. The pot has to be big.

Sincerely,
John A. Keslick, Jr.
Arborist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.