Excellent ! Thanks guys. I started looking last night to find more, now with a name to start. Your right formandfoliage, all the first ones I found are very small in comparison. Sorbaria arborea seems to be the right direction. Then I ran into the name change, since these species were formally included in the genus Spiraea. Went down that path and read parts of a paper about which plants froze and to what extent at Harvard the winters of 1942 and 1943 ...still Spiraea then. Anyway, I've been digging out old books and going various directions on the web comparing the various descriptions. It's been interesting that I keep running into such a mix of languages on the web. This is a well traveled plant. Right now I've decided this is most likely Sorbaria kirilowii . Height of the plant being the main factor, but knowing the same plant can vary by region and this would not be the first time our PNW weather gave a plant an advantage in size. The photo I posted shows the top of the 6 foot fence and that run away branch is about 6 or 7 years old ? I know one friend has been telling me he will help get it trimmed for three years now but we get distracted. You know how that can happen. Looking out back this morning and guessing the height of the current tallest group of trunks I think they are about 18 feet conservatively. They're probably at about 15 years since I whacked them down. Thus the 20 to 26 feet height noted for Sorbaria kirilowii , at 25 to 30 years of age makes the most sense. And the leaves seem to match what photos and descriptions I can find. Best part ? I find I'm more relieved than expected to know for sure this is not a weed because I would have kept it anyway. It serves it's purpose beautify where it's at. Still seem odd to not see others growing in the neighborhood. Here is a link that might be useful: Sorbaria kirilowii This post was edited by plaidbird on Sat, Jun 22, 13 at 13:34

Assuming this is Oncosiphon,some people asked for seeds and I would be glad to provide some but have no idea how to get seeds. I'm not a real gardener, just wanted to know the name of this plant that is all over the foothills north of Phoenix. So if someone could give me a few instructions re how to collect seeds I would be happy to send some off when they are ready. thanks Caroline (OP) Cave Creek AZ

Yes, an awful weed . https://content.ces.ncsu.edu/mulberryweed-fatoua-villosa

The 2nd one looks like a Plectranthus. I don't know which species turns red in tons of sun, maybe neochilius. Are you able to add a closer pic of the bloom? The first one gave me a Plectranthus vibe too, but could be something in Crassulaceae. Is it fuzzy?