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[Flavor, Properties, and Actions]
The flavor is sweet, the nature is slightly warm, and it is non-toxic. It primarily treats carbuncles and sores (Yong Ju), long-standing ulcerated wounds, expels pus, relieves pain, treats severe wind-leprosy (Ma Feng), five types of hemorrhoids, and rat fistula (Shu Lou - cervical lymphadenitis). It tonifies deficiency and treats various diseases in children.

(Bai Zhu grows in the northwest, absorbing the essence of water and marshes. Its color is yellowish-white, its texture is dense and solid like an arrow shaft, and it is flexible and tough like cotton when broken. The variety produced in Mianshang, Shanxi, is considered superior, hence commonly called "Mian Zhu". Some interpret it solely based on its toughness like cotton, which is incorrect.)

Bai Zhu is yellow in color, sweet in flavor, and slightly warm in nature. It embodies the qi transformation of fire generating earth. Earth governs muscles, and fire governs meridians; therefore, it treats carbuncles affecting muscles and sores affecting meridians. When carbuncles and sores persist for a long time, righteous qi becomes weak, causing the qi of the San Jiao to fail to warm the muscles, resulting in chronic, unhealing ulcers. Bai Zhu assists the San Jiao in emitting qi to warm the muscles, thus treating this condition. Before carbuncles and sores rupture, blood transforms into pus, causing unbearable pain. Bai Zhu tonifies qi and assists yang; yang qi transforms blood and expels pus. Once pus is expelled, pain ceases. Severe wind-leprosy, known as Li Yang, occurs when wind-cold pathogens lodge in the meridians and do not depart, leading to the collapse of the nasal bridge, deterioration of complexion, and skin ulceration with leprosy-like lesions. The five types of hemorrhoids—Mu Zhong, Pin Zhong, Chang Zhong, Mai Zhong, and Xue Zhong—are manifestations of heat pathogens overflowing downward. Rat fistula (Shu Lou) results from kidney water toxins overflowing upward into the meridians, causing swelling and ulceration in the neck and nape, presenting as either hollow or protruding lesions, caused by cold pathogens lodging upward. These three conditions—leprosy, five hemorrhoids, and rat fistula—have pathogens in the meridians but manifest symptoms in the muscles and skin. Bai Zhu nourishes meridians internally and muscles externally, making it suitable for all three syndromes. The phrase "tonifies deficiency" refers to replenishing the deficiency of righteous qi, harmonizing the meridians, and enriching the muscles. Children's meridians are not yet robust, their muscles are not full, and their blood and qi are both weak; therefore, Bai Zhu treats various pediatric diseases.

[Continuation of Flavor, Properties, and Actions]
The flavor is sweet and warm, and it is non-toxic. It treats Bi syndrome caused by wind-cold-dampness, dead flesh (numb/stiff skin), spasms, jaundice, stops sweating, clears heat, aids digestion, and can be prepared as a decoction paste. Long-term consumption lightens the body, prolongs life, and prevents hunger.

(Bai Zhu originally grew in the valleys of Nanzheng and is now found everywhere. The varieties from Songshan, Maoshan, and wild ones are superior. The root skin is yellow, the flesh is white, and upon aging, it turns dark red. The texture contains much gum/resin, and there are two types: red and white. The *Shennong Bencao Jing* did not distinguish them, but during the Han Dynasty, Zhang Zhongjing's prescriptions began to differentiate between Chi Zhu (Red Atractylodes) and Bai Zhu (White Atractylodes). These two have differences in nature (mild vs. fierce) and usage (slow-acting vs. urgent).)

(Note: The *Shennong Bencao Jing* mentions only "Zhu," which definitely refers to Bai Zhu. Cang Zhu should absolutely not be confused with it. Comparing the seedlings, leaves, roots, and stems of the two: Bai Zhu leaves near the root are trifoliate, resembling Ban Xia, with upper leaves similar to Tang Li leaves, pale green and dull. Cang Zhu leaves near the root are palmately lobed (3-5 divisions), with narrow, long upper leaves that are bluish-green and glossy. Bai Zhu stems are green; Cang Zhu stems are purple. Bai Zhu roots are finger-sized, sometimes fist-sized, with brown skin and white flesh, turning slightly red when old. Cang Zhu roots resemble old ginger, with dark brown skin and yellow flesh, showing cinnabar spots when old. Bai Zhu tastes sweet initially, then slightly pungent, followed by bitter. Cang Zhu tastes sweet initially, then bitter, with a particularly strong pungency. Bai Zhu has a mild and gentle nature, while Cang Zhu is dry and fierce; they are clearly different herbs. Later generations, noting they share the name "Zhu," both treat the Spleen and Stomach, and have similar effects on wind-cold-damp Bi, assumed the *Jing* referred to both. This likely stems from a lack of deep discrimination. The term "stops sweating" in the *Jing* applies only to Bai Zhu; using Cang Zhu has the opposite effect. Were they mixed up? Regarding Bai Zhu's flavor, the *Jing* says bitter, Tao Hongjing says sweet, Zhen Quan says sweet-pungent, and Zhang Gao says bitter-sweet. Tasting Zhejiang-grown Bai Zhu reveals it possesses sweet, pungent, and bitter flavors. Summer-harvested Bai Zhu has more pungent than sweet notes; winter-harvested has more sweet than pungent, but both ultimately return to bitter. Thus, previous theories each captured a partial aspect without covering the whole. Yin'an corrected the character "bitter" to "sweet" in the original text of the *Jing*, viewing Bai Zhu as a herb that harmonizes Spleen Earth, considering sweet the primary flavor and bitter an accompanying one, thereby adopting Tao Hongjing's view for correction.)

Bai Zhu has a sweet and warm flavor and a fleshy, resinous texture; it is a herb that harmonizes Spleen Earth. It treats Bi syndrome caused by wind-cold-dampness. The *Suwen: Bilun* states: "When wind, cold, and dampness mix and combine, they form Bi syndrome." Bai Zhu is sweet and warm, tonifying Spleen Earth. When Earth qi circulates, muscle qi connects externally to the skin and internally to the meridians, thus treating Bi syndromes caused by wind-cold-dampness. The Spleen governs muscles; treating "dead flesh" (stiff/numb tissue) assists Spleen qi. The Spleen governs the four limbs; Spasm (Jing) involves stiffness and disharmony of the limbs. The Spleen corresponds to the color yellow; Jaundice (Dan) involves yellowing of the body and eyes due to Earth deficiency. By tonifying the Spleen, Bai Zhu treats spasm and jaundice. Stopping sweat occurs because Earth can overcome dampness. Clearing heat removes deficient heat from Spleen Earth. Aiding digestion helps the transportation and transformation functions of Spleen Earth. Preparing it as a decoction paste utilizes its richness to address Spleen dryness; the resulting preparation is sweet, warm, and moistening, bringing Earth qi to harmony. Hence, long-term use lightens the body, prolongs life, and prevents hunger.

Commentary: Taiyin governs damp Earth and belongs to the Spleen, being the ultimate Yin within the Yin. It prefers dryness and dislikes dampness, prefers warmth and dislikes cold. However, Earth requires moisture to irrigate the surroundings, just as land needs rain and dew to generate all things. If it becomes too hot and dry, stagnation occurs, leading to difficult defecation and Spleen constraint syndromes. Bai Zhu prepared as a paste is dry yet moistening, warm yet harmonizing. This reflects the profound intent of the ancient sages in teaching, which students must comprehend.