I planted a swamp white oak 18 months ago. Was just under 5' tall container, mail order from Forest Farm. I had read that swamp whites are slow growers, but mine has been very vigorous. I think buying small is a good strategy because the 10' B&B's at the garden centers will stare at your for a couple years before taking off and require a lot more watering. This guy will catch up with the bigger ones. I just watered mine weekly during the first summer, but did not water at all the second year. Generously mulched w/ leaf compost. Grew like crazy. I had to re-establish the central leader due to heavy deer browsing. After protecting, it easily put on 2-3 feet in height and a ton of density in the second summer. The trunk really bulked up quickly too. Looks like a winner. Fall color is better than expected, kind of a pale orange. In an area like NE Ohio, which is often pretty wet but also goes through some dry spells, swamp whites seem to thrive. Unlike a lot of oaks, they can supposedly handle wet or dry. Northern reds seem to prefer somewhat drier sites. Of course, Northern Reds are still very good trees. If you are dealing with wetness and/or clay soils, an alternative is the Nuttalli. They have the best form of the reds from what I have seen around here and are starting to gain traction. Guy Sternberg developed a nice cultivar (New Madrid) that you can buy mail-order. Just got one of those too.

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.

I kinda got the shade thing down, believe it or not, most of that garden gets a lot of direct sun in the late morning, early afternoon and then again some in the late afternoon from the other direction. My biggest problem under the trees is the MOISTURE content and the hard dry soil. I need to find plants that can tolerate really dry conditions as well as some shade. I have some daylilies and just started adding some epimedium, so far, so good. One area gets less sun and has more moisture and it does well, I have fern and hosta, huchera, tiarella, and some others that do well there. My biggest problem is the area that is dry. Thanks for the direction to the shade forum, I hadn't thought of that as a reference. I guess because my garden does get a bit of sun, and it is dry that I didn't associate the two. I know a lot of the plants you list above like it on the moist side...I tried astilbe when I first started, not the right site at all. Now I am more versed in plants and their requirements and try to match the site to the plant as best I can. Thanks JoAnn

Well, I will say that due diligence does call for as Embo states, filling in information not explicitly asked for. To not do so is a type of negligence. That said, OP does not own the tree, even manages to appreciate the tree (right?) despite potential problems, and quite clearly does not want to harm it...why not do a moderate root cutting and install a bio-barrier type of product? Those work, right? I haven't really used. I pretty much doubt a 12" bonding of concrete would stop stuff for long enough to justify cost. They'll go that low easily, I think.