Looking for a Wild Trigger Species

This may seem a bit strange of a request but I'm looking for a species of small tree or large shrub that produces berries which are appealing to birds, but does not readily reproduce by dropping fruit or seeds in droppings. I'm thinking about making a small fenced space as a restoration experiment and I want to attract birds to sit and poop within the space without contaminating the species that the birds introduce with their droppings, so that I could get a more accurate sample of which species they are eating and how many they're propagating nearby. Ideally I'd want to select a species that has a wide spread, isn't too tall, is native to eastern north america, and has small and/or dispersed leaves to create very dappled shade, not full shade. Really as long as it could function well for the purpose of attracting birds to come and poop without filling the space with offspring of the tree itself, that would be good. doesn't have to be self-fertile, I could plant additional plants nearby for pollination. thanks for reading.

How about blueberries or mayhaws.

I would say, maybe, Eastern Red Cedar, though only females produce fruit. It's hard to say, off the top of my head, beyond that.

thanks for the replies, I will keep these in mind.
does anyone know if serviceberries readily reseed themselves?

Alex Michaud wrote:does anyone know if serviceberries readily reseed themselves?

This could be location dependent to some degree - maybe even variety dependent. That said, I've got plenty of "volunteer" serviceberries, but they're all "independent operators" rather than having babies under them, which suggests to me: 1) that yes, the birds are distributing them and 2) that like our local huckleberry, the seeds actually *need* to go through a digestive tract to germinate.

That's just conjecture based on observation - another observation is the Robins definitely like Serviceberries! (and generally manage to harvest them before I do!)