Sweetgum can get much larger than 30-40 ft in Houston. It drops those annoying thorny seedballs.
What about Trident Maple or Shantung maple that do not get huge? Shantung maple actually look a bit like Sweetgum without thorny seedballs.

Here is a link that might be useful: Shantung maple 'Fire Dragon'

Thanks Lou, funny you should mention maples, I was just browsing the Maples forum here and looking up several trees. It was a little sad to see most maples don't do well in drought conditions and probably need better drainage than the clay down here will provide. Something for us to consider though, thanks. :)

Shantung maple is pretty tough in drought condition. We had really bad drought back in 2005-2006 in Dallas area and Metro Maples had a lot of them and did fine with occasional deep watering. I grew up in Houston so I highly doubt you'd ever see that kind of drought in Houston like that. My mother and brothers (NW Houston) have a lot of shantung maples at their houses. My mother's Shantung maples are thriving.

There is a cultivar of sweetgum that you may want to look for.
It's called 'Rotundiloba'.
It's seedless and it's a narrower form, like 20-30 feet.
Sweetgums, in my observation, are very good about growing narrower when it's crowded, close to other trees, buildings etc on it's own.
One thing you want to be careful of is sweetgums can be difficult to transplant and slow to establish but they are nice trees. There's a shopping center nearby where they used rotundilobas and they look really nice. From a distance I thought they were hybrid poplars or something because of their narrow form and the leaves were all-aflutter..
They tolerate drought but in so doing, they may drop a lot of leaves. But otherwise heat and humidity, no problemo. Clay soil and poorly draining soil is not a problem either.

Definitely try to get one that's b&b.

How tall/wide will a Shantung maple get in around 5 years do you think, Lou? Are they more bushy than standard tree-shape? Hubby has already nixed any multi-trunked trees.

I'll look at the Rotundiloba and ask hubby what he thinks, Cheryl, thanks.

Depending on what size you start with, I would guess around 15x15 for a shantung in 5 years. My experience with shantungs are they can be a little bushy early on and will require some pruning but will not be multi-trunked (unless you want them to be). I have quite a few shantungs mostly for the fact they won't be huge trees and are drought tolerant. I actually planted one in the front to replace a live oak.

There is a native oak to your area called a Durand oak(Quercus sinuata). It would be perfect for the conditions you describe. Nurseries that specialize in native plants might be able to help you find one. Just another suggestion.

Thanks ltruett & dricha, I might think about a shantung for another spot. Durand oak looks like it might eventually get too large (90' x 60') but I appreciate the suggestion. :)

I think we've narrowed it down to a red sunset maple or a sourwood, opinions on those?

Someone hasn't used the Texas Tree Selector.

Dan

Well actually I did Dan but couldn't find anything there I really liked. And although the sourwood is supposed to do fine down here, it's not listed on the TX tree selector. It does say the red maple isn't drought tolerant so we're going to try a sourwood.

Anyone have any experience with the sourwood's growth rate in SE Texas? I find it listed as either slow or medium (and would really like not to have to wait 10 years to stop the live oak roots from coming any closer to the house foundation).

You should reconsider sweetgum if you are having roots close to your foundation. Sounds like it might be too close for a tree. Pictures generally get the creative juices flowing. Sourwoods are allright. They're widely touted as a superb native. The flowers are showy but aside from that I've never found them all that much to write home about. Then again I have yet to find one growing with a symmetical habit or in the sun which might help. Hard to transplant and even harder to find.

The live oak (that the sourwood would eventually replace) is planted about 10 or 12 feet from the back porch, the sourwood would be planted considerably farther back in the yard, near where this pine used to be (it looked fine when we bought the house a year and a half ago, all the needles browned over last summer and we were told it died and had it cut down about 6 weeks ago):

{{gwi:336210}}

ghostlyvision,
Couple more for you to look up. Check into Big Toothed Maple (Acer grandidentatum), and Chalk Maple (Acer luecoderme). Big Tooth is probable the bigger tree, but both are Native to Texas.

Arktrees

Texas Ash would be a candidate if you have decent drainage.
It is however a fairly hard tree to find, but has good fall color, 35' is typical size, drought resistance, etc.

Two other thoughts in the smaller-sized tree category would be Mexican Plum and Redbud, but both of these would probably not attain 35'.

Thanks ark and scot, I'll look those up. :)

Oh, we have an ash out front (next to the sweet gum - POs were big on big trees lol) but I don't think it's a green ash, it doesn't color before the leaves drop.

I wonder about South Sugar Maple. I planted Chalk Maple (a variant of sugar maple that is native to east Texas somewhere) at my mom's and for the past 3 years, it grew very slow. Maybe I got a really slowing seedling, who knows?

About my shantung maple ... my first one was planted in spring of 2006 as a 5 feet, maybe a bit less. Now, I would guess 16 ft tall and 8 ft wide now. Keep it in mind that where I live is very windy that can slow down growth a bit. My mother's grew faster due to lack of wind there. They will stay bushy if not pruned properly and early. {{gwi:336211}}From Fire Dragon

Now... {{gwi:336212}}From Fire Dragon

'Fire Dragon' shantung maple fall color (most are typically bright yellow). {{gwi:336213}}From 2010 fall color

Typical bright yellow fall color {{gwi:334209}}From 2010-11-23

I need to explain that the large Shantung maple you see in the first picture is more narrow than last year because I cut down two big lower branches to raise canopy over the winter so I can walk underneath while mowing, etc.

Not much difference than others, really. I've seen plenty of mature trees of all kinds with very low branches that homeowners never bothered to cut off long time ago.

Nice looking trees, Lou.