here's a link to a discussion about trees and sidewalks:
http://tree-tech.com/board/?topic=topic5&msg=412
k
For more info about the International Society of Arboriculture, please visit
http://www2.champaign.isa-arbor.com/.
For consumer info about tree care, visit
http://www2.champaign.isa-arbor.com/.../consumer.html