I enjoy looking closely at details to nail down a positive species-level identification (see my Aster ID post), but sometimes specificity is best left to professional botanists. According to GoBotany, the Hawthorns (genus Crataegus) comprise "the second largest number of species of any genus of vascular plants in New England" with nearly 50 difficult-to-differentiate kinds. Luckily, sorting them out to the species level is not required to forage them responsibly -- according to Arthur Haines, "their uses are similar (though some species have larger flowers and fruits than others)."*
Prior to this fall, I hadn't encountered many fruit-filled hawthorns, but I happened to notice this planted tree outside the library where I work. The young leaves, along with the flowers and fruit, are said to be edible and high in antioxidants. Hawthorns are also well-known heart tonics. The only way I've tried this plant, aside from a few raw fruits, is as an alcohol extraction of purchased dried fruit. Herbalist Deb Soule of Avena Botanicals shares more about the gifts of Hawthorn in the video below.
*Ancestral Plants (2010), page 70.