One way to decide on a tree for the garden or the community, is to shop the neighborhoods, looking for street trees or trees on someone else's property that might be just what you want. You can see how big the tree is, how dense its shade, how destructive its roots. The catch, of course, is that you might not know the name of the tree you are looking at.
But several communities have books on their trees. The latest is "Trees of San Marino," by Wendy Stubley, published by the Huntington Botanical Gardens, which lists over 50 of the trees growing in that city, and examples of where they can be found. A map identifies the locations. There are also drawings of each tree and its leaves (and sometimes flowers or fruit). It is available at the Huntington's book store or may be ordered by writing to Huntington Library Publications, Department T, 1151 Oxford Road, San Marino, Calif., 91108.
On the Westside, with its very different climate, you can explore Pacific Palisades, with "Trees of Pacific Palisades," by Grace L. Heintz, in hand. This too comes with a map and it lists over a hundred different trees, on 272 pages. It costs $5 (which includes postage) and is available from Palisades Beautiful, P.O. Box 1072, Pacific Palisades, Calif. 90272.