Hi. I found a volunteer tree or shrub growing in my back yard and hope
someone can help identify it for me.

The picture is posted on alt.binaries.pictures.gardens with the subject of
"ID volunteer tree." The first photo is a detail of the leaf, the second is
the whole plant in a 3-inch pot. It is doing quite well on my sunny window
sill.

I live in California, zone 9b, Sunset zone 15.

The leaves are (I think this is right) pinnate, arranged opposite, elongated
lance-shaped and toothed. Stem is woody. Closest matches I could come up
with are sumac, jacaranda, or mountain ash, although none seem exactly
right.

Any ideas? TIA.

- Dewolla Stepon