The fruit clusters are distinctive and provide an excellent tool to identify the genus Carpinus. The nutlets of Carpinus betulus are subtended by a 3-parted bract with the middle lobe the longest. The bracts are produced in pairs and face each other. They are very similar to the fruits of Carpinus caroliniana with slight differences in bract features and size. The clusters change in color from green to yellow to brown as they mature.
Piero Amorati, ICCroce-Casalecchio di Reno, Bugwood.org
Betulaceae, Carpinus betulus, European hornbeam, common hornbeam, deciduous, tree