Orobus nipponicus (Matsum.) Stank. & Roskov
Vicia nipponica is a herbaceous perennial plant with rather stiff, ascending stems 30 - 80cm long[
The plant is sometimes harvested from the wild for local use as a food.
E. Asia - Russian Far East, Japan
Grows all over Japan[
Species in this genus generally succeed in any well-drained soil in a sunny position if the soil is reliably moist throughout the growing season, otherwise they are best grown in semi-shade[
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[
Young leaves - cooked[
Seed - sow in situ in spring or autumn. The seed has a hard seedcoat and may benefit from scarification before sowing in order to speed up and improve germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing.