White fresh skin (Rutaceae). 

White fresh skin, alias: White moss skin, eight strands of cattle, mountain peony, fresh Leymus chinensis, Latin name: CORTEX DICTAMNI Chinese medicine name. It is the root skin of white fresh and narrow leaf white root bark of perennial herbs of Rutaceae. Mainly produced in Liaoning, Hebei, Sichuan, Jiangsu and other places. The roots were dug in spring and autumn, the sediment and rough skin were removed, the root skin was peeled, sliced and dried. For living. It has the effect of clearing heat, dryness and dampness, dispelling wind and detoxification. "Theory of Drug Nature": "treatment of all heat and poison wind, evil wind, wind sore, scabies red rot, eyebrow hair brittleness, skin muscle urgent, strong heat and cold; main solution heat yellow, wine yellow, acute yellow, valley yellow, labor yellow and so on." In modern research, the volatile oil has anticancer effect in vitro. But the spleen and stomach deficiency and cold people use carefully. 

Morphological characteristics. 

Rutaceae plants. 

White fresh is a perennial herb, base woody, as high as 1m. The whole plant has a special fragrance. Root fleshy, multiple lateral roots, outer skin yellow-white to yellowish brown. Odd pinnately compound leaves alternate; leaf rachis narrowly winged, petiolate; Leaflets 9 to 13, leaf blade ovoid to elliptic, 3.5-9 cm long, 2-4 cm wide, apex acute, base cuneate, margin serrulate, dark green above, dense glandular spots, white green below, glandular dots sparse. Racemes terminal, as long as 30cm, rachis and pedicels mixed with white pilose and black glandular hairs; pedicel 1-2.5cm long, with 1 linear bract at base; sepals 5, ovoid-lanceolate, ca. 5mm long, ca. 2mm wide, base healed; Petals 5, pale red and purplish red lines, oblanceolate or oblong, ca. 25mm long, 5-7mm wide, tapering stalks: stamens 10; ovary superior, 5-loculed. Capsule, densely glandular hairy, 5-lobed at maturity, each piece apex with a needle tip. Seeds 2 to 3, subglobose, ca. 3 mm in diam., apex mucronate, black, glossy. The flowering period is from April to May and the fruiting period is June. 

Narrow leaves, fresh perennial herbs, high 30-80cm. Stems erect, mostly branched from base, densely long tomentose, lower part smooth sometimes with short hairs, scented. Leaves alternate with odd pinnately compound leaves; leaf rachis hairy, base not winglike; petiolules very short; Leaflets 7-15, oblong or oblong, 5-10 cm long, 2-3 cm wide, apex acuminate, base broadly cuneate or subobtuse, margin finely serrate, curly downward, smooth above, sparsely white hairy along veins below. Inflorescences racemose, inserted at apex of stem, densely covered with dark brown glandular hairs and light brown hairs; bracts linear-lanceolate, densely dark brown glandular hairy; sepals 5, lanceolate-linear, 7-9 mm long, apex acute, densely glandular hairy; Corolla lanceolate or oblong, 2-4.5 cm long, pale pink, purple-brown hairy, apex acute or obtuse, base gradually contracted clawed; stamens 10, separated, filaments all hairy; ovary superior, with sparse white hairs, style smooth. 5-lobed at maturity, each with a tip at the apex. Seeds 2 to 3, subglobose, black, glossy. The flowering period is from May to July and the fruit stage is from August to September. 

The authentic white fresh skin is quite similar to the wrong Caragana, but as long as we grasp four key points: the authentic white fresh skin is slightly slippery, the cross-section is layered, there is sheep smell, and the taste is slightly bitter. On the other hand, Caragana has a long lenticel on the surface, powdery cross-section, fibrous, smelling beans, slightly sweet taste. You can tell the difference between true and false. 

The fresh root bark was reel-shaped, 5-15cm in length, 1-2cm in diameter and 2-5mm in thickness. The outer surface is grayish white or grayish yellow, with fine longitudinal wrinkles and fine root marks, often with raised granular dots; the inner surface is white and has fine longitudinal lines. Brittle, broken when there is dust flying, the cross-section is not flat, slightly lamellar, peeling off the outer layer, the small bright spot that flashes to the light. With the smell of sheep, the taste is slightly bitter. Those with large strips, thick meat, gray bags and separated sections are the best. 

Cross section of root bark: White cork layer is 10. 

The rest of the cork cells. The cortex is narrow and has large transverse fissures. The phloem is wide, the arrangement of cells is loose, there are fissures, and the phloem ray width is 1 to 3 rows of cells. Cortex, phloem scattered with a single fiber, square-like or long polyhedral, the wall is very thick, wooded. This product parenchyma cells contain starch grains and calcium oxalate cluster crystals. 

Growth environment. 

Ecological environment: born in mountain bushes and under forests, sunny slopes. Bai Xian was born in the bushes on the soil slopes, in the bushes in the mountains and under the forests, on the sunny slopes of the mountain slopes. Bai Xian likes warm and humid, cold-resistant, afraid of drought, afraid of waterlogging, afraid of strong moving picture light. 

Distribution range. 

Distribution of resources: northeast, East China and Shaanxi, Gansu, Henan, Sichuan, Guizhou, Xinjiang, Yili, Altay area is the most. 

Heilongjiang, Jilin, Liaoning, Inner Mongolia, Hebei, Shandong, Henan, Shanxi, Ningxia, Gansu, Shaanxi, Xinjiang, Anhui, Jiangsu, Jiangxi (northern), Sichuan and other provinces and regions. Born in hilly slopes or flat bushes or under grasslands or sparse forests, limestone mountains are also common. North Korea, Mongolia, Russia (far East) also have.