I saw this in Penticton BC area about 3 weeks ago, growing wild with sumac and native plants. To me the stems and thorns look like a rose, but the opposite leaves etc don't. Maybe it blew in? I'm wondering if it's a native plant too. Thanks for any suggestions
I posted some photos of these at Appreciation: - Thorny issues, and spines and prickles, the first five photos. The new growth often or usually has the prickles, which are no longer present as the tree ages. Robinia pseudoacacia - Wikipedia says it's endemic to only a few small areas in the eastern US, invasive in many other areas in North America.
The leaves are of course not oppositely arranged. Neither are the leaflets. So if that aspect happened to come up in a dichotomous key being used selecting "opposite" would not lead to the right result.
@Silver surfer Awesome! Thanks very much @Ron B Very good, thank you for the clarification here @wcutler Those are interesting pics, esp highlighting its suckering. I think I saw it last year in the Castlegar area. A shrub - they were smaller than a tree - caught my attention because of its leaf arrangement and there were quite a few. I had no idea what it could be. I stopped to take pics and was pretty surprised by legume seed pods on it, like a caragana. It makes sense now if it's the same. It seems to be. I didn't notice the thorns last year, but there are some. It's definitely outside of its native range. (I've not seen these in Alberta.) Castlegar pics & map (Wikipedia)
