Texas Gardening: ?? tree, 1 by indirt

indirt wrote:
I would like to know what kind of tree has 2-5 simple (they each seem to have their own stem, anyway) leaves coming out of a single node. The leaves are elliptical, 3-5" long with a narrow pointed tip, light green, and has opposite veining. The twigs have short spines or thorns - mostly at base of node, but sometimes elsewhere. I don't see any sign of flowers or fruit/seeds. The entire tree is about 20' with a caliper of about 5 inches. The bark is shallowly fissured in a long diamond shape.

Is it a "weed tree" or a "keep tree"?