Polygonum aviculare rigidum (Skvortsov) H.C.Fu
Polygonum rigidum is a much-branched, erect to ascending annual plant that can grow around 30 - 50cm tall[
The plant is harvested from the wild for local use as a food.
Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people.
Many species also contain oxalic acid (the distinctive lemony flavour of sorrel) - whilst not toxic this substance can bind up other minerals making them unavailable to the body and leading to mineral deficiency. Having said that, a number of common foods such as sorrel and rhubarb contain oxalic acid and the leaves of most members of this genus are nutritious and beneficial to eat in moderate quantities. Cooking the leaves will reduce their content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[
E. Asia - Siberia, Russian Far East, Mongolia, northern China
Near fields or roadsides, shaded grassy places in valleys; at elevations from 400 - 2,500 metres[
Species in this genus generally succeed in an ordinary garden soil, whilst preferring a moisture retentive not too fertile soil in sun or part shade[
]. They generally rpays generous treatment[
Most plants in this genus seem to be immune to the predations of rabbits[
Leaves and young shoot tips - raw or cooked. An emergency food, used when all else fails[
We have no specific information for this species, but the seed of most, if not all, members of the genus is edible both raw and cooked, and is potentially a good source of amino acids. Unfortunately the seed is also usually rather small and fiddly to utilize[
Seed - sow in situ