Senna splendida (Vogel) H.S.Irwin & Barneby (Syn: Cassia splendida Vogel; Cassia splendida var. angustifolia Benth.); 

Image by  Ken 


Fabaceae-Caesalpinioideae (Caesalpiniaceae)– Senna splendida: This is a small tree, native to (chiefly) Brazil that is occasionally grown in Southern California, USA. Light orange-yellow flowers for a few weeks in Fall.

Would be interested to know the exact month of flowering of these species. I plant my next visit to California in April, 2013

These photos were taken mid-October. Unfortunately, this particular specimen was later butchered by a gardener who did not know what he was doing! Hopefully it can regrow some next year. ……………

I have seen this in orange county California as street/landscape tree near new parking lots etc and one at the airport… usually at end of summer or even early fall… seems to be a “new” introduction…
not listed in Urban forestry street tree guide:
site of LA county

This is grown by Monrovia Nursery in Los Angeles County, typically sold as a standard for home landscapes.
Unlike Cassia species, Senna species are generally easier to root from cuttings. Monrovia grows this vegetatively for uniformity. It does set some seed, but they can be variable and weak from seed.