Tom,
We had Pawpaw wild where I grew up. They grew alongside redbuds in a truly understory location. They would sprout and grow to fruit stage underneath mature stands of elm, hackberry and hickory. We didn't have maples in my part of Missouri much. They didn't grow much where it was brushy or in a dense thicket, but in open woods where the mature trees were spaced out a bit - they were mostly in shade with a dappled sun effect. We went to the woods to search for Morel mushrooms in the second week in April, and the Pawpaws were blooming with their little brown tulip blossoms, and the redbuds blooms were sharing space with tiny heart shaped leaves at that time of year. Pawpaws didn't grow much more than 8 feet tall - and I never saw one with a large trunk - maybe a 3 inch diameter max. Best of luck with your Pawpaws!
