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*Shennong Bencao Jing* (Divine Farmer's Materia Medica) records that Polyporus (Zhu Ling, 猪苓) promotes the flow of water passages but does not mention its ability to arrest thirst; yet when Zhang Zhongjing named a formula with "Polyporus," he certainly administered it only after the patient exhibited thirst. How can one claim it is without efficacy? Zou believed that Polyporus raises Yin Qi (vital energy associated with Yin) to harmonize Yang and transform water, akin to maple leaves turning red and subsequently falling. Although *Bencao Jing* and *Mingyi Bielu* lack texts on "raising Yin," an examination of *Erya Zhengyi*, *Shuyi Ji*, *Yitong Zhi*, *Nanfang Caomu Zhuang*, *Wulei Xianggan Zhi*, and Xun Bozi's *Lin Chuan Ji* reveals various spiritual phenomena associated with maple trees that indeed resonate with Yin Qi. Polyporus grows beneath maple trees; its skin is extremely black, and its flavor and aroma are both thin. It may well be capable of raising Yin. Moreover, once the water passages are unblocked and the San Jiao (Triple Burner) becomes patent, the Kidney Qi ascending via the San Jiao will naturally moisten and irrigate the chest (as explained in *Shiming*: Thirstiness arises because Kidney Qi fails to circulate throughout the chest). Thus, how can thirst fail to cease? This shares similarities with Alisma (Zexie, 泽泻) arresting thirst. However, there are aspects where it falls short of Alisma. Alisma is round in shape with a single stem growing straight upward; it can raise Yin from the lowest depths to nourish Yang at the highest peak and pacify excessive Yang heat at the summit. Polyporus is sweet and bland and cannot ascend directly to the head; therefore, Alisma Decoction treats dizziness and vertigo, whereas Polyporus is not included therein. Nevertheless, the Yin nature of Polyporus contains Yang, enabling it to open the interstices (Cou Li, 腠理) and reach the exterior. In this regard, it is comparable to Poria (Fuling, 茯苓), a capability Alisma lacks. Wuling San (Five-Ingredient Powder with Poria) and Zhuling Tang (Polyporus Decoction) treat floating pulse and fever precisely because they contain Polyporus and Poria. Comparing Polyporus to Poria, their commonality lies in being herbs for the Taiyang (Greater Yang) and Yangming (Yang Brightness) channels. What merit does Polyporus have to rival Poria? Both Poria and Polyporus aggregate in the earth; both have white flesh; both are sweet and bland. Yet Poria's whiteness is bright and pure, while Polyporus's whiteness is dark and rugged. Poria, being sweet and bland, obtains the correct flavor of Earth; Polyporus, also sweet and bland, obtains the biased flavor of Earth. This explains why Poria has a broad scope of indications, while Polyporus has a narrow one.

Bamboo is green and hollow inside, resembling the Gallbladder as a clear and pure organ that has no exit or entry. Bamboo sheath (Zhuru, 竹茹) is sweet and slightly cold, which aligns with the Gallbladder's preference for mild warmth. Therefore, Scutellaria (Huangqin, 黄芩) is an herb for Shaoyang channel heat, while Bamboo Sheath is an herb for Shaoyang fu-organ heat. Ancient formulas treating Gallbladder heat frequently used Bamboo Sheath, yet later generations, lacking knowledge, failed to recognize it as a Gallbladder herb. The causes of hiccups (Yue Ni, 哕逆) vary; if Stomach deficiency allows Gallbladder heat to invade, hiccups may occur. Jupi Zhuru Tang (Tangerine Peel and Bamboo Sheath Decoction) uses Ginseng, Jujube, and Licorice to tonify Stomach Qi and nourish Yin; Tangerine Peel and Ginger to harmonize the Stomach and scatter rebellious Qi; and Bamboo Sheath to eliminate Gallbladder fire, thereby clearing the source of hiccups. Jupi Tang excludes Bamboo Sheath because cold hands and feet indicate Liver Qi rebellion. During lactation, women often suffer from middle-jiao deficiency and Gallbladder heat; Gallbladder heat inevitably invades the Stomach, causing vomiting, rebellious Qi, and even restlessness due to severe heat. Zhupi Dawan (Bark Large Pill) employs Gypsum and Anemarrhena to clear Stomach heat and anchor floating Yang; Bamboo Sheath cools the Gallbladder and clears the source. Fearing that the deficient middle-jiao cannot tolerate cold herbs, Cinnamon Twig is added for its acrid-sweet properties to guide the action. Since the prescription balances Yin and Yang, Licorice is added to harmonize. If wheezing occurs, Platycladi Seed is used to regulate Liver Qi, further assisting the limitations of Bamboo Sheath.