Library

[Sanbai Cao (Three-White Grass)]
Taste: Sweet, Pungent. Nature: Cold. Toxicity: Slightly toxic. Indications: Edema (fluid retention), Hongjiao (swelling and pain in the feet/legs), promotes urination and defecation, resolves phlegm, breaks up blood stasis and masses, dissipates carbuncles and sores. Habitat: Grows by pools and marshes.

Note from *Bencao Tangxin* (Newly Revised Materia Medica of the Tang Dynasty): The leaves resemble *Polygonum orientale* (Japanese Knotweed) or *Houttuynia cordata* (Fish Mint), and also resemble *Smilax* species. There are three black spots on the leaves; the plant is about one chi tall. The root resembles that of celery, yellowish-white and thick. According to Chen Cangqi's *Supplement to Materia Medica*, Sanbai Cao, when crushed and its juice taken orally, induces vomiting and regurgitation, clears heat disorders in the chest and diaphragm, and treats malaria and pediatric pi-man syndrome (abdominal masses). Examination shows that when this herb first sprouts, it lacks whiteness; entering summer, half of the leaf tip turns white like powder. Farmers use it to time rice transplanting; when the third leaf appears, the grass tassels, hence the name "Sanbai" (Three Whites). The mention of "three black spots" was a secret kept by ancients; thus, previous annotations claiming this were based on ignorance and speculation. Its leaves resemble *Dioscorea opposita* (Chinese Yam) and do not resemble *Polygonum orientale*. (This note is appended to *Bencao Tangxin*). Ministers Yu Xi et al. carefully examined *Shu Ben Tu Jing* (Illustrated Classic of Shu Province), stating it originates from Xiangzhou, with roots harvested in February and August.

[Lu Ru (Root of Euphorbia lathyris / Spurge Root)]
Taste: Pungent, Sour. Nature: Cold, slightly cold. Toxicity: Slightly toxic. Indications: Erodes foul flesh and necrotic tissue in ulcers, kills scabies mites, expels pus and foul blood, clears heat from wind-pathogens causing forgetfulness and depression, removes heat-bi syndrome, breaks up zheng-jia masses (solid abdominal masses), eliminates polyps. Alternative names: Quju, Lulou. Habitat: Grows in valleys of Daijun. Harvested in May, dried in shade. Those with black heads are superior. (Gancao [Licorice Root] acts as its guide drug; incompatible with Maidong [Ophiopogon Tuber].)

Tao Hongjing stated: The best variety comes from Goryeo, with a yellow color. When freshly broken, the exuded juice coagulates into a black substance resembling lacquer, hence called "Lacquer Head." The second variety comes from nearby regions, named Caoru, which is white. Sellers often burn iron to char the root ends to mimic the "Lacquer Head," which is not authentic. Leaves resemble *Euphorbia lathyris*; flowers are yellow; it grows in February; roots also treat sores. Ministers Yu Xi et al. carefully examined *Shu Ben Tu Jing*, stating the leaves contain juice, the root resembles a radish, with yellow skin and white flesh, found everywhere.

*Tujing* (Illustrated Classics) states: Ru grows in valleys of Daijun; currently found in Heyang, Zizhou, and Qizhou. Sprouts appear in February; leaves resemble *Euphorbia lathyris*, with yellow flowers. Roots resemble radishes, with reddish-yellow skin and white flesh. Freshly broken juice coagulates black like lacquer. Flowers appear in March, pale red or light yellow, without seeds. Tao Hongjing’s description of the Goryeo variety aligns closely with this. Roots harvested in April and May, dried in shade. "Lacquer Head" varieties are superior. Another variety, Caoru, is white; gatherers char the ends with hot iron to pass them off as Lacquer Heads, which is inauthentic. However, ancient formulas used both types. Yao Sengyuan treated carbuncles and sores with foul flesh using Bai Ru San (White Ru Powder); once the foul flesh was gone, he stopped and applied various plasters. If new flesh did not grow, he applied Huang Ru San (Yellow Ru Powder). If foul flesh remained, he used Chi Pi Ru (Red-Skinned Ru) with a black head, powdered, mixed with three qianbi of Bai Ru, and applied externally for cure. Thus, both red and white types are usable.

*Shenghui Fang* (Holy Essential Formulas): Treats Huan Ju (slow-developing abscess). Use one liang of Ru, powdered, taken with warm water, two qianbi per dose, at any time. *Shanghan Leiyao* (Classified Essentials of Cold Damage) treats throat swelling caused by cold-damage toxin attacking the throat: take a piece of true Ru the size of a fingernail, chew in the mouth, swallow the juice; slight efficacy is ideal. Annotation on *Suwen* (Plain Questions) states: Ru primarily disperses foul blood.

*Yanyi* (Expanded Meaning) states: Ru treats scabies, particularly effective for equine scabies. It is rarely used in dietary therapy formulas.