Ostrya's a genus of eight to ten small deciduous trees belonging to the birch family Betulaceae. Its common name's Hophornbeam in American English and Hop-hornbeam in British English. It may also be called ironwood, a name shared with a number of other plants. The genus's native in southern Europe, southwest and eastern Asia, and North and Central America. They've a conical or irregular crown and a scaly, rough bark. They've alternate and double-toothed birch-like leaves 3-10 cm long. The flowe… (More on Hop-hornbeam)