Orobus davidii (Hance) Stank. & Roskov
Lathyrus davidii is a herbaceous perennial plant growing from a tuberous rootstock; the strong, erect to decumbent stem can be 100 - 180cm long, attaching itself to nearby supports by means of tendrils[
The plant is harvested from the wild for local use as a food and a mediine. It is sometimes grown as an ornamental.
Although no specific records of toxicity have been found for this species, the seed and other parts of many Lathyrus species contain a toxic amino acid. It is produced in the plant at about the same time that the seed starts to develop. In small quantities the amino acid is innocuous, and the seeds of several Lathyrus species are eaten as a nutritious part of the diet. However, in larger quantities (the seed should form less than 30% of a balanced diet), it can cause a very serious disease of the nervous system known as 'lathyrism'. Symptoms appear as a paralysis of the muscles below the knees, pains in the back, followed by weakness and stiffness of the legs and progressive locomotive incoordination[
E. Asia - Russian far East, northern China, Japan, Korea
Woods and thickets all over Japan[
]. Hill slopes, forest sides and bush-woods; usually at elevations up to 1,800 metres[
Lathyrus davidii is a moderately cold-hardy plant, able to tolerate temperatures down to around -20°c when fully dormant[
An easily grown plant, succeeding in any moderately good garden soil but preferring a position in full sun[
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[
Seed - cooked[
]. Some caution is advised, see the notes above on toxicity.
Young seedpod - cooked[
]. The seedpods are around 100mm long and 6mm wide, containing several seeds[
Young plant, including the inflorescence - cooked and used as a potherb or added to soups etc[
The plant (part not specified) is diuretic and tonic[
Pre-soak the seed for 24 hours in warm water and then sow in early spring in a cold frame[
]. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.
If you have sufficient seed, then it can also be sown in situ in mid spring[
Division in spring. It may not transplant well so care should be taken[