An eastern cottonwood would gives some dense shade pretty quick. They take the heat well and they are native. They do have weak wood though....

This post was edited by greenthumbzdude on Sat, Mar 9, 13 at 18:38

There are a lot of options to choose from. A couple of questions for further clarification: What do you mean by root problems above or below ground--not planting over water or field lines? How large of an area do you have to plant on in the backyard?

I think the septic is far enough away not to ever interfere.. but I know there are some maples for example with roots that have caused problems with us having to mow over them as they extended above the ground.. we have a large enough area for a shade tree to be, large yard.. this tree would be away from our house but close to our outdoor building,, I just don't know enough to know how far roots can extend..

Take a look at Shumard Oak. Many oaks are large, strong-wooded and give good shade. Shumards have attractive leaves and may hold a lot of them well into winter, if you like that. The leaves are large and attractive. This is a popular oak that gets very large and grows pretty fast, from what I understand.

Richard.

I'll second the oak recommendation.
Shumard is good, but bur oak is my fave - and it is native to KY, adaptable to a wide range of soil types/pH, drought-resistant once established, and quite fast-growing.
I'll warn against pin oak - which may be the most common oak you're likely to find in the local nursery trade. If you have alkaline soil, chlorosis may be a problem; I'm seeing nice big pin oaks taken out here by a double-whammy of bacterial leaf scorch and horny stem/branch galls - and, until you limb them up like a big ol' lollipop, pin oaks have downsweeping branches that are perennial eye-pokers.

I like the oaks suggestion. I might add for a fast-growing instant shade tree, consider Yellow-poplar/Tulip poplar. These are good hardwoods with spring flowering and nice yellow fall color. Plus no surface root problems. The tree is also hospitable to being under planted (with discretion) with a flower bed.

Tulip poplar is easy to plant when young. They get fleshy orange colored roots best planted ASAP.