If you leave the Pin oak it will be too big? Is that the problem? You may need to have trees pretty far from the garden.I guess it will be best to wait for pics.

Deciduous choices: 1. A small native tree, cercis occidentalis (Western redbud). Gets to about 15 feet. Usually grows as a multi-trunk. Usually blooms better inland where it gets colder. Attracts hummingbirds. Doesn't bloom heavily near the coast where I live. Rounded shape and leaves. Well-behaved rootwise. Mine is 5 feet from our pool. 2. Chaste tree (vitex agnus-castus). Great, reliable summer bloomer, even near the coast. Attracts hummers and butterflies. Roots well behaved--ours is also 5 feet from the pool like our cercis occidentalis. To about 15 feet. We've grown ours as a multi-trunk. Some people like to keep the tree trimmed as a large shrub. (You can see a small portion of the Western redbud in the foreground to the left.) 3. Forest pansy redbud (cercis canadensis). This one blooms better (at least in my location) than my native redbud.

Thank you so much for all your input! Just got a chance to sit down. First of all, I live in San Francisco Bay Area, specifically in the upper Peninsula. The tree in the first photo has a lot of fruits, and some birds like to eat it. But I don't know if it's edible for man. The plant in the 2nd photo dries in late summer or early fall (all the leaves), seem to die, but will grow up again in later winter. I've not seen it in blossom yet.

Planting a yoing tree in the boarding rock bed the hot summer sun would cook it the freezing winter would freeze the root system. Planting in rocks need least 3-4 foot from base of tree to bottom of canopy. Blooming fruitless trees request fertilizer if not they're a short life span. Today's tree care we can plant just about any type of tree in your yard long as the soil can be mended to host the tree. As arborist we can speed up tree growth to fill in landscaping or we can slow growth down to keep the tree in check from out growing the landscape. We can stop fruit production with yearly injections. when planting a tree it's always a good idea to talk with a local arborist in your area about the types of trees that will work best for your landscape they already know what works an what doesn't work with the soil in your area.