Q: My children want a tree house. Can we build it on pine trees? The branches are too high so we plan to build it on three trunks that are near each other.

A: When my son was a toddler, I built a 12 foot by 12 foot platform around a large pine tree in my woodsy side yard. It is 6 feet off the ground, supported on 4×4 posts. I made a 3 foot high railing around it for safety. He, and other kids in the neighborhood, loved climbing up to it and spying on activities in the neighborhood. Treehouses built haphazardly by kids can be dangerous. Tree expert Dr. Kim Coder has good construction guidelines at Tree-Literate Treehouses