You might look into Allamanda laevis. I know that the difference between 10a and 10b in California are the Allamanda's. They wont take the wetter colder bay area winters..frost or no frost.

I looked at A. laevis and the leaves are not the same. The leaves on the neighborhood tree are very narrow, rolled, and dark green, compared to the diamond-shaped, medium green leaves of A. laevis.

More likely what you're talking about is a Thevetia or Tecoma stans.

Thevetia and Tecoma stans are two different plants and completely different. As I said before this tree is NOT Thevetia, although it is probably in the same family - Apocynaceae.

I'm certainly not trying to question your knowledge, but are you sure it's not Thevetia thevetoides (Giant Thevetia)? There's a very nice specimen of this small tree (multi-trunk) on Park Blvd just north of SD Zoo. The flowers on this Thevetia are very different (much more ornamental) than the ones on the more common Thevetia peruviana.

Hi Bill,
You da man! It is indeed Thevetia thevetoides. I was only aware of Thevetia peruviana, and I knew it was not that. Thanks everyone for the input. I have been trying to figure this out for a couple of weeks.

Do you know if it is easy to propagate? A couple of twigs have migrated to my house. I cut off most of the leaves, and halved the ones I left. I dipped the cuttings into rooting hormone and have them in a pot. One article I read, suggested covering the cuttings with a plastic bag to increase humidity. Do you think that this step is necessary or will it lead to fungus growth?

And exactly where in your first post had you mentioned that you knew it wasn't Thetvetia? Some people...
I resisted the initial urge to tell you that there is no tree form lof Allamanda that you would see growing in San Diego.

So sorry Bahia,
I have posted in other sites and specifically mentioned in one that T. peruviana was next to the mystery tree and that they didn't look the same. My mistake, thinking I had posted the same information here. I knew it wasn't T. peruviana, Allamanda cathartica, A. schottii, A. laevis, but I didn't know what it truly was. i have been googling for two weeks and these were the only species I could find. Articles mention, "There are several species" but do not elaborate.

Looks like a great outdoor plant-might be a good potted plant too. Should do fine for most of the bay area out of direct view of the Golden Gate.