Paul Crabtree
Paul Crabtree is CEO of Crabtree Group, specializing in civil engineering in support of excellent town planning, Smart Growth, New Urbanism, green infrastructure, rainwater practices, and integrated sustainable infrastructure.
Root zone: Tips for healthy street trees
This drawing offers a lot of information for the maintenance of healthy street trees, which are critical to urbanism. A rule of thumb is that tree roots will not penetrate soils compacted to greater than 85 percent. Most concrete sidewalk specs call...