I am intrigued. You really should try to get a picture posted for us in order to aid in identifying.

May be a Palo Verde. Cercidium. Hard on people with allergies and asthma.

Desert Willow? IF the house is new and the planting relative new the tree has a long way to go. Gets huge. We had one that lifted our block fence after about 5 years. It sheds pods and 'strings' profusely. Messy.

Thank you for all your responses so far. When looking further into the Palo Verde suggestion and pictures of them it sounded right until the description mentioned thorns - this one has no thorns. Do they have a thornless version? Also, I can't really tell whether it is going to flower...it doesn't look like it so far.

The desert willow decription says it has bark and brown leaflets...no bark, no brown. It's all green.

I'll try to get a picture posted.

This tree is potted in a very large pot

Could it be a pencil euphorbia? Or a bottle tree, maybe? Try a Google search in the Images section for those two.

THAT'S IT! It's a Pencil Euphorbia! Thank you EileenAZ for helping me identify it.