Carpinus laxiflora

About

Carpinus laxiflora, the aka-shide, loose-flower hornbeam, or loose-flowered hornbeam, is a species of flowering plant in the family Betulaceae, native to the Korean Peninsula, and Japan. A deciduous tree of mountain forests, and typically 10 to 15 m tall, it is used in bonsai, and rarely as a park or street tree. It is available from commercial suppliers. In addition to the rather rustic unimproved species, a weeping form called 'Pendula', and a sport with variegated leaves called 'Variegata' are available.

Summary from Wikipedia