The locations appears to me to preclude having a small tree with a decurrent-type/rounded-canopy form, unless you want to go with a bonsai specimen. I would recommend either planting considerably further out or sticking with some type of shrub-like plants.

Moving further out, if possible, would also eliminate the problems you are likely to experience from the soil amendment. Planting a tree in amended soil can be a very bad idea for multiple reasons. In your case, one of those could include a "bathtub effect" where the amended soil has exaggerated moisture levels (both wetter in moist times and drier in drier times, than surrounding/native soil). Amended soil also frequently results in root system problems.

the reflected heat and sun may be problematic also ...

what about trellis and some vine to cover the windows...

or awnings ....

ken

Bush/tree options:
Desert Willow excellent drought resistance and flowers.
Chiltalpa (cross of desert willow x Catalpa)gets slightly bigger. (drought resist. and more flowers-may want to move this one further from house)

Small tree/bush options - should be planted further away than what you are showing (5-15'):
Redbud - Texas and Mexican varieties. There is a native California variety if it is available. Excellent drought
resistance and spring flowers.
Mexican Plum - excellent small tree for shade. Spring flowers, interesting bark. Mine grew 28" last year with
weekly watering.
Crepe Myrtle - reliable standby flowering shrub/tree. Used for shade and flowers. The white varieties have scenic peeling bark.
All of these are used fairly often in Z8&9 Tx.

scot..

will all those fit in the existing bed????

what would you recommend for proper siting ...

i am asking.. because this zone.. and these plants are totally foreign to me ...

no matter what tree you plant .... i would suggest we are talking 3 to 5 years for any impact... presuming they are properly sited ..

so the resolution of your problem.. is most likely going to be two fold ...

ken

I'm with Ken and Brandon. Way too close to the house to plant a tree.

I believe all the suggestions Scot listed are deciduous and the OP wants evergreen non-conifer. There are evergreen viburnums like Burkwood Viburnum that might make a good fit there. They should be planted at least 4-5' from the house IMO though.

Here is a link that might be useful: 2/3 of the way down the page is a list of evergreen viburnums

I missed that you wanted tree shape. While viburnums can be pruned to tree shape, I believe they resist it by suckering but I am no viburnum expert by any means. Have you given thought to the evergreen holly trees?

John

Would a nice clumping bamboo work in that climate?

ken
Desert Willow will definitely fit in that space, that close to the house. It is about like a slow-growing Yaupon. It will eventually need pruning but should work well in that spot for years to come.
The Mexican and Texas Redbud should be ok there, but would prefer to move them out to 6' away. These are smaller than standard Eastern Redbud. Unsure of California Redbud but believe it to be similar to Mexican Redbud.
The others should be moved further out as mentioned.
This appears to be the gable end of her house, so the height isn't as critical a factor as on the other sides.

Sorry, I missed the non-deciduous part. Reading too fast.
Yaupon Holly is a std. evergreen used close to houses with red berries. Don't like it under eaves as in 10 yrs it will need to be cropped. On gable side of house it would be a good choice. Most people grow them as multi-trunked, but can be trained as single-trunk.

Mrs Coffield,
Are you still with us? Comments? Questions? Answers?

What evergreens are native to your area?
Are there evergreen oaks? How about an olive tree. With hundreds of sorts, they must vary in growth character.
Most are hardy down to about 10 F.
If you can water, the list might be vast.

"Are there evergreen oaks? How about an olive tree. With hundreds of sorts, they must vary in growth character."

Yes, both oaks and olives are commonly bonsai-ed, but I'm not sure how they'd hold up with that exposure (reflected heat, etc).