A shrub to about 6 ft high; branches slender, glabrous at maturity. Leaves narrowly to broadly lanceolate, 2 to 3 in. long and up to 1 in. wide, soon glabrous, the margins set with hook-like, finely pointed teeth except at the entire acuminately tapered apex, bright green above, glaucous or grey beneath; petiole up to 1⁄4 in. long. Catkins appearing with the leaves; scales ovate, obtuse, sparsely hairy. The female catkins are slender and remarkable for their length, being up to 5 in. long even in the flowering stage, the male to 3 in. long. Stamens two, free. Ovary stalked, glabrous, with a short style. Both male and female flowers have a single nectary.
Native of Japan. A handsome species of uncertain affinity but certainly not related to S. babylonica, of which Andersson, the monographer of the genus, inexplicably considered it to be a ‘minor modification’. It may not be in cultivation, but is worthy of introduction, for its distinctive foliage and long female catkins.
For the willow introduced as S. japonica Lavallei see under S. babylonica. Another willow grown in the last century as S. japonica, a female clone, may have been one of the allies of S. jessoensis (q.v.).