Due to differences in local dialects, potatoes or sweet potatoes are indeed called yam in some places, but the correct term is yam: also known as Huai yam, Huai yam, and mountain mushroom. It is the tuber of Dioscorea, a perennial herbaceous plant of the Dioscoreaceae family.
Plant form: twining herbaceous vines. The stems are usually purple-red. The single leaves are alternate at the lower part of the stem and opposite above the middle part; the leaves are ovate-triangular to broadly ovate or halberd-shaped, with large variation, deep heart-shaped base, and often 3-lobed to 3-deep lobes at the edge. The flowers are unisexual, dioecious, and form elongated spikes; the capsule is triangular and oblate or triangular in shape, with white powder on the outside. The flowering period is from June to September, and the fruiting period is from July to November.
Grows on hillsides, valleys, understory, or in bushes or weeds by streams, roadsides. Mainly produced in Henan.
Collection: Dig the rhizomes in autumn or winter, remove the soil and fibrous roots, cut off the reed heads, wash them, soak them in water and scrape the skins, fume with sulfur repeatedly and dry them in the sun. Some are smoked with sulfur, rolled into cylindrical shapes with wooden boards, cut into sections, dried in the sun, and polished.
Yam tablets/hairy yam/glossy yam
Yam tablets: irregular flakes, with a white surface, powdery texture, and a light and slightly sour taste. Fried yam with bran is commonly used in prescriptions. After frying, it turns bright yellow and has a burnt aroma.
Hairy yam: slightly cylindrical, curved and slightly flat, 15-30cm long, 1.5-6cm in diameter. The surface is yellowish-white or brownish-yellow. If the outer skin is not completely removed, it will appear light brown. There are longitudinal grooves, longitudinal wrinkles and fibrous root marks. The ends are uneven, brittle and easy to break. The cross-section is white, powdery, light in taste, slightly sour, and difficult to chew. stick.
Light yam: cylindrical shape, flush with both ends, 10-18cm long, 1.5-3cm in diameter. The thickness is uniform, straight, the whole is white, smooth and round, and powdery enough.
Meridian distribution of nature and flavor: sweet, flat. Returns to the spleen, lung, and kidney meridians.
Effects and Applications
1. Nourish the lungs and relieve cough: It can be used for deficiency of lung qi, chronic cough and asthma, or deficiency of lung and kidney and inability to absorb qi.
2. Tonify the spleen and stop diarrhea: It is mainly used for spleen deficiency, loose stools, or excessive leucorrhea in women due to spleen deficiency and dampness injection.
3. Tonify the kidney, strengthen the essence and reduce urination: it can be used to treat kidney deficiency, insufficiency of the Yuan, spermatorrhea, and frequent urination.
In addition, this product is often used to quench thirst for those with Qi and Yin deficiency.
Dosage and usage: 10-30g, large amount 60-250g. Grind into powder and swallow, 6-10g each time. It should be used raw to nourish yin, and stir-fried to strengthen the spleen and relieve diarrhea.
Usage precautions: Do not take it if there is excess moisture or stasis