These are Castor Bean seedlings that have popped up under my full grown plants this fall. I usually have quiet a few seedlings that pop up the following year after growing these. When I find them like this they seem to be shallow rooted and can be pulled out very easily and planted in the place you want them to grow.
I would say that they are perennial for my zone (which is 7)
So all the seeds that hit the ground will surely make a new plant! Once you see the seedlings you can spot them from a far, just be sure and check the grass before mowing and you'll find plenty!
Common name: Castor Bean, Caster Oil Plant
Family: Euphorbiaceae
Genus: Ricinus
Species communis
Plant Link: http://plantsdatabase.com/go/70/
