Dealing with alleopathic trees

I'm moving to a small plot of land in southern California, throughout the area there are a ton of California bay trees which are allopathic, they are cut to look like massive hedges. I was wondering if there was any secret to planting near allopathic trees and if there was anyway that I could use the mulch from these trees.

You can find lists of plants that tolerate each tree, and then use those plants as barriers. For example, off the top of my head I think mulberry is immune to walnut and has a big enough root system that you can plant the mulberry in between the walnut and intolerant plants. At least I -think- it was mulberry, but either way the concept is there.

what kinds of tree are growing naturally with the bay trees in your area?