Elm: Identify American, Slippery, and Winged Elms by Spring Samaras
https://www.inaturalist.org/journal/lisa281/31314
These three native elms all flower and fruit in the spring, before leaves arrive. The fruit of elms is a flat, rounded samara, with a central seed surrounded by a thin wing. Here's how to identify American Elm, Slippery Elm, and Winged Elm from these samaras.