var. koreana is an originally-come-from-Korea deciduous
shrub approximately 2-4m in height, the branches extending long
sideways in an arrow way. The phyllotaxis is the opposite; the
leaves are 5-10cm long, 1.7-3cm long, in an oval shape, with keen
serrations on the upper half margins. Dioecious: dark yellow
blossoms about 3cm in diameter appear before the leaves develop.
Bloom time: March-April.