Prunus americana. An excellent pollinator option for American plums. The small but abundant fruits make great plum sauce and jam, or can be dried. Can be pruned as a small tree, or let the suckers grow for a more shrubby thicket (be aware that they have thorns). Low maintenance.
Provides a solid food source and habitat for tons of wildlife. Also a host tree that supports native bees and butterflies. Grows up to 20 feet tall.