The Chinese yam, Dioscorea batatas, is widely cultivated in Asia. The tubers are eaten raw, grated, marinated or cooked. The Chinese yam is now considered an invasive species in the United States.
The genus Dioscorea is named in honour of Greek pharmacologist and botanist Pedanius Dioscorides. Polystachya comes from Greek poly & stachys: having many spikes.
Description and flowering period
Dioscorea polystachia is a climbing or scrambling herbaceous vine measuring from 3 to 5 meters. The leaves are mostly cordiform (heart-shaped), but have an elongated central lobe. They are glossy and have numerous veins. At the leaves’ base, small aerial tubercles (less than 2cm) can be found, each of which can generate a new plant if planted. The small flowers are white and smell like cinnamon. The species is mostly grown for its large underground cylindrical or spindle-shaped tubers. They can each reach over 4 kilograms and 1 meter long. Each plant can produce one or more of these underground tubers which are the only part of the plant used for human consumption.
- Food & drink: Tubers can be eaten raw, grated, marinated and cooked. They are known as ‘tororo’ in many Japanese recipes.
- Medicinal: Antioxidant, anti-inflammatory and analgesic properties. Used in ayurvedic and traditional Chinese medicine to treat rheumatism and ovarian troubles, it is also used in weight-loss treatment.
Widely grown in Asia where it is known for its medicinal properties. Its Chinese names translate as “Mountain medicine”. The species has been introduced in the United States at the start of the nineteenth century and is nowadays considered as an invasive species.
Translated by: François Saint-Hillier – MNHN