Library

Bai Tou Weng (Pulsatilla Root), grows in the valleys of Mount Song, and is now found in all prefectures near the capital. Seedlings emerge in the first lunar month, growing in clumps; they resemble Bai Wei (Cynanchum atratum) but are softer, finer, and slightly longer; leaves grow at the tips of the stems, covered with fine white hairs that are not smooth or glossy, and have white down near the root, resembling an old man with white hair, hence its name; the root is purple, deep as a turnip; it blooms with purple flowers and yellow stamens in the second and third lunar months, and bears fruit in the fifth and sixth lunar months. Its seedlings remain still when there is wind but sway when there is none, similar to Chi Jian (Gastrodia Rhizome) and Du Huo (Angelicae Pubescentis Radix). The roots are harvested in the seventh and eighth lunar months and dried in the shade for use. Modern folk physicians often combine it with tonifying medicines, which yields great efficacy, and it is also suitable for frail individuals.

Ru (Rhubarb), grows in the river valleys of Dai Commandery, and is now also found in Heyang, Zizhou, and Qizhou. Seedlings emerge in the second lunar month; the leaves resemble Da Ji (Euphorbia pekinensis) and bear yellow flowers; the root resembles a radish, with reddish-yellow skin and white flesh; when freshly broken, the exuded juice coagulates into a black substance like lacquer; it blooms with pale red flowers, also faintly yellow, and does not set seed. Tao Hongjing stated that those from Goguryeo are closest to this variety. The roots are harvested in the fourth and fifth lunar months and dried in the shade. Those with a lacquer-like head are of superior quality. There is another type of grass Ru with white coloration. Harvesters sometimes scorch the head with a hot iron to blacken it, passing it off as lacquer-headed Ru, which is not genuine. However, ancient prescriptions utilized both types. Yao Sengyuan treated foul, malignant flesh arising from carbuncles and ulcers by applying Bai Ru San (White Ru Powder); once the foul flesh was removed, treatment ceased, and only various plasters were applied. If new flesh did not grow, Huang Qin San (Scutellaria Powder) was applied. If the foul flesh persisted, Chi Pi Ru with a lacquer head was ground into powder; half a qian bi dose was mixed with three qian bi doses of Bai Ru San and applied together, resulting in recovery. This indicates that both red and white varieties are usable.

Yang Ti (Rumex crispus), also known as Tu Cai (Bald Vegetable), grows in the marshes of Chenliu and is now found everywhere. It thrives in damp, low-lying areas. Seedlings emerge in spring, reaching three to four chi in height; the leaves are narrow and long, resembling Wo Ju (Lactuca sativa) but darker in color; the stem joints are purplish-red; the flowers are pale blue-white arranged in spikes, and the seeds are three-angled, resembling Chong Wei (Leonurus japonicus), withering in midsummer; the root resembles Niu Bang (Arctii Fructus) but is solid and firm. Nowadays, people harvest fresh roots, grind them with vinegar, and apply the paste to tinea for rapid effect. They can also be decocted into pills. The prescription uses newly harvested Yang Ti roots, in any quantity, pounded, ground, and pressed to obtain one da sheng of juice; half a jin of white honey is added, and the mixture is boiled until thick like syrup. Then, six liang of Fang Feng (Saposhnikoviae Radix) powder is added and kneaded to form pills the size of wu zi (mulberry seeds). These are taken with wine infused with Gua Lou (Trichosanthis Radix) and Gan Cao (Glycyrrhizae Radix), three to twenty pills per dose, two to three times daily, which is optimal. According to the "Xiao Ya" section of the *Book of Songs*: "Gathering its Xu." Lu Ji stated: "Xu," now called Yang Ti by people, resembles Lu Bo (Radish) but has a red stem; it can be cooked as a vegetable, being slippery and delicious. Excessive consumption causes qi to descend. People in Youzhou call it "Xu." The character is sometimes written as "Xu" (pronounced chi liu qie). Another variety is extremely similar but has yellow leaves and a sour taste, named Suan Mo (Rumex acetosa). The *Erya* refers to "Xu," i.e., "Sun" Wu. Guo Pu stated: "Wu" resembles Yang Ti, with fine leaves and a sour taste, edible, also known as "Xi" (pronounced xiu).