I understand your neighborhood is doing pretty much the same thing in creating a canopy. I like the idea. It's different, but if everybody goes along with it, it should work. Sort of an island for bird life in the city. Trees, when planted properly, and irrigated when needed, grow surprisingly fast. I wouldn't worry about overplanting, you can always edit or limb up. The thing I wouldn't do would be to plant trash trees. They get in the way all too quick. Nor would I plant trees that can't handle shade. Here's what I did about 25 years ago. Some would say it's over planted. Those are the people who look at each plant as an individual, rather than the plants as a composition. Their trees are arranged as if they were knick-knacks on a shelf. To each his own, of course.

Thanks to everyone for their responses. I guess we have to rule out Japanese Maple since our front yard is south-facing and gets full sun. We were visualizing a tree with foliage that is full and rounded, and about 5-6 feet off the ground. We don't want anything shrub-like mainly for aesthetic reasons. We'd like the tree to shade the house in the summer and allow the sun to come through in the winter. Below the tree, we'll have succulents and drought-tolerant plants, with much of the ground cover being pea gravel. I'm still looking up all the various suggested trees on the web to see what they look like... but please keep your suggestions coming! Also, if you can recommend a good nursery in the San Diego area, I'd appreciate those as well!

Yes! Joereal. Thanks. Joecool is/was from Florida. My mistake. Mental lapse. Joe mentioned sometime around 2000-05 that it is possible to plant more than one tree in a hole to save room and I think make pollinating easy. I can't remember the discussions, but now that I'm back, I'd like to know more about this type of growing. I believe there was someone from mid-east coast that also was doing this. I suppose I should go to find pros? This site is so different from when it started, I'm not sure what to do. Again thanks.

The yard isn’t tiny, but it is only slightly larger than a typical suburban back yard. We definitely want shade, we get relentless sun back there and it makes it hard for grass to grow. Behind our fence is a ditch and then begins the yards of the neighbors behind us, not a park unfortunately. We do love the idea of looking out our windows and seeing trees as opposed to all the houses behind us (we are on the top of a hill overlooking a large neighborhood.. we see a lot of brown siding out our window right now). I feel like the pin oak is in an okay spot to not interfere with our neighbors, but the tulip will definitely reach our neighbor’s deck on that side. So I guess it’s the one that needs to go. Makes me really sad because I LOVE that kind of tree, but I know it does get big.