✵The TCM herbalism is also known as pharmaceutics of Traditional Chinese Medicine, or Chinese pharmaceutics, is the branch of health science dealing with the preparation, dispensing, and proper utilization of Chinese herbs. It is majorly composed of Introduction of Chinese Medicinals, Classification of Chinese Herbs, Formulas, and Patent medicines.
Classifications of Herbs:Dispelling Wind-Damp Herbs.
Introduction: Dispelling Wind-Damp Herbs: an agent or substance herbs that dispels wind and damp, mainly for relieving rheumatism and related conditions.
✵Till the date Oct 10th,2019, there are totally  kinds of common TCM herbs,  kinds of related plant species, are recorded in this category. These dispelling wind-damp herbs are briefly introduced separately:
Rhizoma Dioscoreae Nipponicae(Chuan Di Long).
Brief Introduction: The herb Rhizoma Dioscoreae Nipponicae is the dried rhizome of Dioscorea nipponica Makino(family Dioscoreaceae), used to dispel wind-damp, activate blood circulation, unblock collateral meridians and resolve phlegm in the treatment of rheumatalgia, sprain, traumatic pains, and chronic cough with expectoration. The herb is commonly known as Rhizoma Dioscoreae Nipponicae, Chuān Dì Lónɡ.
✵Official herbal classics defined the herb Rhizoma Dioscoreae Nipponicae(Chuan Di Long) as the dried rhizome of (1). Dioscorea nipponica Makino. Other famous herbal classics defined the herb Rhizoma Dioscoreae Nipponicae(Chuan Di Long) as the dried rhizome of (1). Dioscorea nipponica Makino., (2). Dioscorea nipponica Makino subsp.rosthornii(Prain et Burkill)C.T.Ting. They are plants of the Dioscorea genus, Dioscoreaceae family, Liliflorae order. These 2 commonly used species are introduced as:
(1).Dioscorea nipponica Makino.: It is commonly known as Chuān Lóng Shǔ Yǔ. Herbs perennial twining, up to 5 meters long. Rhizome transverse, cylindrical, woody, much-branched, cork layer markedly exfoliated. Stem sinistral, cylindrical, subglabrous. Single leaves alternate; Leaf 10~20 cm long; Leaf blade palmately cordate, variable, stem base leaves 10~15 cm long, 9~13 cm wide, margin unequal triangular lobed, middle lobed or deeply lobed, apex leaf blade small, nearly entire, surface yellowish-green, glossy, glabrous or sparsely white pilose, especially dense in veins. Flowers unisexual, dioecious. The male inflorescence is an axillary spike, the base of the inflorescence is usually 2~4 integrated umbels, the top of the inflorescence is usually a single flower. Bracts lanceolate, apex acuminate, shorter than perianth; Perianth discoid, 6-lobed, lobes apex obtuse; 6 stamens, inserted in the center of perianth lobes, anthers introverted. Female inflorescence spicate, solitary; Perianth 6-lobed, lobes lanceolate; Pistil stigma 3-lobed, lobes 2-lobed. Capsule pale yellow at maturity, triangular, apex concave, base nearly rounded, each rib winged, varying in size, generally about 2 cm long and 1.5 cm wide. Seed each chamber 2, sometimes only 1 development, grows at the base of the central axis, all-round have unequal thin film shape wing, the upper part is rectangular, length is about 2 times than width. Its flowering period is from June to August.
Ecological Environment: the plant grows on slopes, forest sides, river valleys and bushes at an altitude of 300~2,000 meters. It is distributed in north, northwest (except Xinjiang), the middle and lower reaches area of the Yangtze River, and other areas of China.
Trait identification: Rhizomes cylindrical, slightly curved, branched, 10~15 cm long, 0.3~1.5 cm in diameter. Surface yellowish-white or brownish yellow, irregular longitudinal groove, with punctuate root marks and protruding stem marks on one side, occasionally membranous light brown skin and fine roots. The quality is hard, the section is flat, white or yellow-white, scattered has light brown vascular bundle small point. Slight smell, bitter taste.
(2).Dioscorea nipponica Makino subsp.rosthornii(Prain et Burkill)C.T.Ting.: It is commonly known as Chái Huáng Jiāng. The main difference between this subspecies and the original subspecies is that the plant is thick and strong, the rhizome has no spayed cork, the flowers have more or less stalks, the number of chromosomes is 40, and the content of potato saponins in the rhizome is low, the average is 1.25%. In terms of geographical distribution, they are transitional plants in the warm zone, distributed in central China south of Qinling mountains. In addition to its different morphological characteristics, Dioscorea nipponica has a chromosome of 20 and a high content of 1.5-2%. It is distributed in northern China to the north of the Qinling mountains and belongs to the temperate zone. Its flowering period is from June to August, fruiting from August to October.
Ecological Environment: It grows in the valley thickets and sparse miscellaneous wood forests with an altitude of 1,000~1,800 meters and the forest margins. It is distributed in the south of Qinling mountain in shaanxi and the south of Gansu, Hubei, Sichuan, Guizhou and other areas.
Trait identification: Similar as the rhizome of Dioscorea nipponica Makino. Only the rhizome is thicker, smooth surface, no exfoliation.