Quiz: Remember the definition of mal de mer?
(Betula populifolia), slender ornamental tree of the family Betulaceae, found in clusters on moist sites in northeastern North America. Rarely 12 m (40 feet) tall, it is covered almost to the ground with flexible branches that form a narrow, pyramidal crown. The thin, glossy, dark green, triangular leaves have long, thin stems and flutter in the wind. In one variety, the leaves are purplish when young