BTW, irrigation system and underground utilities run through the beds at the
house and along the planting beds bordering my neighbors property lines so
rototilling is out. We also sit about 100 ft. back from the street, so
there is lots of ground for us to cover. Any other suggestions for what
besides trees grow in these conditions would be welcomed.

I deal with the same type of soil in the Dallas area, and neither of
the plants you mentioned will do well in it as is. I dont agree that
tilling is out of the question. If you have the room to do it, raised
beds are the best solution. If not, check and see how deep the
sprinkler pipes are. Electrical and plumbing lines should be at least
2 feet deep, tillers only go down 8-9 inches. Call the phone and
cable companies to mark their lines. In Texas we have a 1-800 number
that coordinates marking all utility lines free. In new houses in our
area, sprinkler pipes are generally put in at least 18", just watch
for the heads.

Use compost instead of topsoil if you till it, use a premixed planting
mix if you raise the beds.

Good luck,
Bryan