The first plant popped up in a flower garden. We dubbed it EG (the Enthustiastic Grower). It's about 8 feet tall.
The second plant (OMP- Other Mystery Plant) came up in the vegetable garden. That might be relevant because household vegetable scraps get buried out there. These things have been coming up all summer, but it's tailed off quite a bit in the last month. I'd say I've dealt with at least 1,000 seedlings, maybe 2,000. I let this one grow just to try to get a handle on what the heck it is. It's about 4 feet tall at the moment. They're mostly confined to an area about 12 feet in diameter, but their range extends out to close to a 20 foot diameter.
If anyone knows what these guys are I'd *really* appreciate it if you'd share!! My mother's been gardening here for over 60 years, and she's stumped.