Spiderweb Blue Ear Grass (Lushuicao)
Dew Grass(Lushuicao露水草), also known as Spiderweb Blue Ear Grass (Cyanotis arachnoidea C. B. Clarke/蛛丝毛蓝耳草), is a perennial herbaceous plant from the Commelinaceae family. The entire plant is covered in spiderweb-like white hairs; its roots are thick and root-like; the leaves are grass-like or strap-shaped; the stem leaves are alternate, elongated-ovate, with a gradually pointed or blunt tip; the bracts are large and leaf-like; the petals are blue-purple, blue, or white; the capsule is small, wide, and three-angled; the seeds are gray-brown with small pits; flowering occurs from June to September, and fruiting happens in October.
Spiderweb Blue Ear Grass is distributed in southern China and Taiwan, as well as Southeast Asia. It is highly adaptable, with slightly fleshy leaves that can tolerate strong light and drought, preferring sunny conditions. It reproduces both asexually and sexually, with cultivation techniques available.
This plant has therapeutic benefits including warming the meridians and collaterals, dispelling dampness, and relieving pain. It is used to treat rheumatic arthritis, limb numbness, and other symptoms; it also clears heat, detoxifies, cools the blood, and stops bleeding for conditions such as edema, beriberi, urinary difficulties, nosebleeds, hemorrhages, dysentery, sore throat, erysipelas, abscesses, and snake or insect bites. For preparation, clean and chop the plant, simmer with pork for 90 minutes, and season with salt and MSG.
Morphological Characteristics: Spiderweb Blue Ear Grass is a perennial herb with a height of 30–50 cm. The stems are clustered, erect or slightly inclined at the base, and flattened. The leaves are linear, 10–25 cm long and 3–5 mm wide, often rolled inward with a gradually pointed tip; the leaf sheaths are flat with white soft hairs at the sheath mouth; the leaf tongue is truncate. The inflorescence is a pyramidal cluster, 15–18 cm long, with branches nearly whorled or single, often twisted; the spikelets are slender with 3–8 small flowers; the glumes are lanceolate with a pointed tip and veined; the outer lemma is ovate-lanceolate, arranged loosely, and the inner lemma is slightly shorter, often persistent with a truncate tip; the anthers are yellow. Flowering and fruiting occur from April to September.
Distribution: Spiderweb Blue Ear Grass is found in India, Sri Lanka, Vietnam, Laos, Cambodia, and Southeast Asia. In China, it is distributed in the southern mainland regions, Taiwan, Fujian (Xianyou, Pinghe, Nanjing, Zhangpu), Jiangxi (Longnan), Guangdong (Meixian, Wengyuan, Dinghu, Liannan, Lianping, Huaiji, Guangzhou, Huiyang), Hainan (Chengmai, Baoting), Guangxi (Nanning, Lingchuan, Longlin, Shanglin, Guiping, He County, Lingui), Guizhou (Pan County, Xingren, Anlong), Yunnan (Yanshan, Mengzi, Cangyuan, Tengchong, Pingbian, Xishuangbanna, Fengqing, Jingdong, Kunming, Qujing), and Zhejiang (Yueqing, Pingyang, Cangnan). It grows in valleys, stream banks, and moist rocks below 2700 meters above sea level.
Growth Habits: It has strong environmental adaptability, with slightly fleshy leaves that tolerate strong light and drought, and it prefers sunny conditions. It grows well in high mountain plains and general soils, particularly in warm, moist, and loose fertile environments at around 2000 meters above sea level. It does not tolerate heavy frost and goes dormant in winter.
Main Value: The whole plant is used in medicine, with benefits such as warming the meridians and collaterals, dispelling dampness, and relieving pain. The primary active ingredient is p-sitosterol, which constitutes 1.2% of the dried plant weight, with up to 2.9% in the rhizome. It treats rheumatic arthritis, limb numbness, and other symptoms, and also clears heat, detoxifies, cools the blood, and stops bleeding for conditions such as edema, beriberi, urinary difficulties, nosebleeds, hemorrhages, dysentery, sore throat, erysipelas, abscesses, and snake or insect bites. For preparation, clean and chop the plant, simmer with pork for 90 minutes, and season with salt and MSG.
Properties and Indications:
- Taste and Nature: Sweet taste, neutral nature.
- Functions: Dew Grass has cooling, cough-relieving, and pain-relieving effects.
- Cough Relief: Combine Dew Grass with garlic and Platycodon root, simmer and drink to treat whooping cough caused by weakness and insufficient lung Qi due to cold.
- Pain Relief: Chew Dew Grass or drink as a decoction to treat acute abdominal pain.
Related Formulas:
- For Whooping Cough:
- Dew Grass (5 qian), garlic (3 cloves), Platycodon root (2 qian). Simmer and drink.
- Dew Grass root, dried and ground into powder (0.5 to 1 qian), take with ginger syrup.
- For Acute Abdominal Pain:
- Dew Grass root (3 qian). Chew or drink as a decoction.
