A deciduous shrub free from down in all its parts, very much resembling D. mezereum in growth. Leaves oblanceolate, tapered at the base to a short stalk, rounded or shortly pointed at the apex, 2 to 3 in. long, 3⁄8 to 1 in. wide, dark dull green. Flowers shortly stalked and produced in lateral clusters with the leaves, greenish yellow, nearly 1⁄2 in. wide; lobes ovate, rounded at the end. Fruit red, oval, 1⁄3 in. long.
Native of Central and South Japan; named by Gray in 1858-9 from specimens collected by Charles Wright. It was introduced around 1910 but had probably been in cultivation before and lost. It is easily recognised by its similarity to the mezereon in leaf and growth and by its yellowish flowers being produced when the plant is leafy. The bark is tough and fibrous.
D. kamtschatica Maxim. – This species, in its typical state, is a native of Korea, the Russian Far East, Sakhalin and the Kuriles. It is represented in cultivation by the following variety:
var. jezoensis (Maxim.) Ohwi D. jezoensis Maxim. – A native of Japan in subalpine woodland, differing from D. pseudomezereum in its obovate-oblong leaves, rounded at the apex, and its yellow, fragrant flowers. It was in flower in the Alpine House at the R.H.S. Garden, Wisley, in March 1968. Typical D. kamtschatica, which is probably not in cultivation, differs from the variety in its narrower leaves and smaller flowers.