Here's another pic of this plant occupying a larger area.

Hello.

Could it be this? Crown vetch? Invasive!

Here is a link that might be useful: crown vetch

Had a tip from a poster on another forum, and I think it's Goat's Rue (tephrosia virginianum). It's def not crown vetch - I knew that, but the foliage does look to be of the vetch family so it made me wonder. It's quite lovely - just have to wait for it to go to seed now, and collect!

Look up web pictures of the various pea-family members. There's quite a lot of them. You're on the right track in that this is surely one of them. I'm still picking out what's what in that tribe so I don't feel qualified to ID your plant, at least based on those pics.

Mountian pea, uh....see, I can't even remember the names....but there are some natives in that bunch. There're also more non-native, invasive types besides crown vetch. I think we see one around here called cow vetch which does all the same things. But I'd look to some web-based picture collections to home in on this one.

+oM

It's goat's rue.....don't try to transplant it...it won't transplant. Typical of many pea family plants....collect seeds.