John,

It sounds to me like you are describing Mexican Paloverde:

http://aggie-horticulture.tamu.edu/o...iaaculeata.htm

Mexican Paloverde is not a particularly invasive plant, except in disturbed
soils and in Australia. In Central Texas it is sometimes helpful in
stabilizing hillsides and helping fight erosion. Paloverde can be a good
landscape plant, but they do have thorns.

jjhnsn