Earth of Water: Baizhu 白術

味苦皆屬水，地黃為之主，黃芩為木，黃連為火，白術為土，竹葉為金。
All bitter belongs to water; it is governed by Dihuang, Huangqin is wood, Huanglian is fire, Baizhu is earth, and Zhuye is metal.

The Tang Ye Jing lists Baizhu (白術) or Atractylodes Root as the Earth of Water. We know from basic Five Phase thinking that Earth controls or restrains (ke 克) Water, and it is this relationship between Earth and Water that is exemplified by Baizhu.

This means Baizhu is an indispensable herb in treating disorders involving dampness and fluid metabolism. The Shen Nong Ben Cao Jing emphasizes these qualities in its entry on (Bai)Zhu:

術　味苦溫。主治濕痺、死肌、痙疸，止汗除熱，消食 … 久服輕身、延年不饑。一名山薊。生鄭山山谷。

Zhu tastes bitter [and its flavor is] warm. It governs damp obstruction, dead muscles [i.e. atrophied or weakened muscles], tetany, jaundice, stopping sweating, eliminating heat, and dissolving food [i.e. supporting digestion]….protracted taking lightens the body, prolongs life, and eliminates hunger. Its other name is Shan Ji (“Mountain Thistle”). It grows in Zhengshan’s mountains and valleys.

All of the diseases listed in this passage involve dampness, and effect the Spleen, the Earth Organ Network, which is responsible for the circulation and metabolism (or “transportation and transformation”, yun hua 運化) of fluids as well as nutrition derived from food. Spleen dysfunction leads to pathological fluid accumulation, described as dampness (濕) in Chinese Medicine. Conversely, the presence of dampness encountered in the external environment can encumber the Spleen, disrupting these vital functions.

From a Five Phase perspective, dampness results from a failure of Earth to control Water. Chapter 23 of the Huangdi Neijing Suwen informs us that the Spleen is averse to dampness (脾惡濕), and Chapter 22 of the Suwen advises us that “when the Spleen suffers dampness, urgently eat Bitter to dry it.” (脾苦濕，急食苦以燥之) It is the Bitter flavor, which the Tang Ye Jing associates with Water, that will enable the Spleen to re-establish control over fluid metabolism.

We can understand this by considering the quality of movement associated with the Bitter flavor in Suwen Chapter 22: bitter consolidates (jian 堅). The key to grasping Baizhu’s action lies in this movement, and in understanding the etymology of the term jian. The character jian 堅 could also be translated as to solidify, harden or fortify. The ancient dictionary Shuowen Jiezi 說文解字 defines jian as “earth that is made firm” (堅: 土剛也) and notes that it is composed of two component characters, 臤 which means strength (and is also a component of the character for Kidney 腎) and 土, which means soil or Earth in the context of the Five Phases. Thus character used to describe the action of the Bitter flavor literally means “to firm up earth”.

When we dry something, it becomes solid, firm and hard. Likewise, when soil is consolidated it is firm, and when it is firm it can serve as a dam that can contain water. These connotations would have been obvious to the ancient Chinese, whose civilization depended upon the proper management of rivers to sustain agriculture. This firming, hardening quality itself however belongs not to Earth, but to Water. It is in the Winter months that the soil becomes hard, as Cold congeals, freezes, and solidifies the ground. This is why the same component character 臤 appears both in 堅 as well as in the character for Kidney 腎, the Water Organ Network. Consolidation is an essential part of the movement of storage 藏 which is the fundamental movement of Winter and the Water Phase.

Baizhu, c/o Kamwo Herbs

By imbuing the Earth with the firming quality of Water, the Bitter flavor of Baizhu is able to dry dampness, promote fluid metabolism and bank up the Earth to control Water.
This is the primary use of Baizhu in Zhang Zhongjing’s formulas.

We see Baizhu frequently paired with Fuling, the Water of Earth, in formulas like Wuling San (五苓散), Ling Gui Zhu Gan Tang (苓桂朮甘湯) and Zhenwu Tang (真武湯) where it functions to dry damp and disinhibit water. In contemporary practice it is common to focus on the Spleen as a digestive organ, and thus we consider dampness primarily as involving digestive symptoms like loose stools. However, there are many other functions of the Spleen and many other ways that dampness can manifest in the body.

For example, the Spleen also governs the four limbs, and another important use of Baizhu is in disorders involving joint pain that involves dampness, as in Gancao Fuzi Tang (甘草附子湯), and Guizhi Shaoyao Zhimu Tang (桂枝芍藥知母湯). These formulas are used in the treatment of wind-cold-damp obstruction, the first disease listed by the Shen Nong Ben Cao Jing that Baizhu governs.
Dampness is often a key pathological factor in obstruction or bi syndrome (痺證); the Shuowen Jiezi defines obstruction as “dampness disease” (痺: 溼病), and if we analyze the character for obstruction we see that it is composed of the disease radical 疒 over the phonetic component bei 卑. When bei is combined with the flesh radical 月, this forms the character pi 脾, or Spleen. We can see how the use of Baizhu would be indicated in these kinds of conditions.

The largest dosage of Baizhu in Zhang Zhongjing’s formulas is in a somewhat obscure formula called Tianxiong San (天雄散), at eight liang of Baizhu. Tianxiong San is listed in Chapter 6 of the Jingui Yaolue alongside the formula Guizhi Jia Longgu Muli Tang (桂枝加龍骨牡蠣湯), both of which are indicated in the treatment of a pattern of deficiency taxation 虛劳 characterized by a loss of essence (失精).

Why would Zhang Zhongjing suggest using a large dose of Baizhu in a formula to treat a pattern characterized by loss of essence? We can understand this high dose in terms of the dynamics of Earth and Water; insofar as essence belongs to Water, the large dose of Baizhu is there to utilize the control cycle to staunch the loss of essence, firming Earth to restrain Water.

This use of control cycle dynamics between Earth and Water has implications that go beyond herbal medicine. For example, it may partially explain why in Master Tung acupuncture, certain sets of points on the Spleen Channel like the Lower Three Emperors (Xia San Huang 下三皇 77.18, 77.19, 77.21) can be used to benefit the Kidney.

It’s my hope that this exploration of the Five Phases through the Tang Ye Jing will be of interest and benefit to practitioners of Chinese Medicine, regardless of whether you are practicing with herbs, acupuncture or any other modality. Fundamentally, the study of these ancient texts provides us with information about the cycles of physiology, and how these physiological cycles are a reflection of the cycles of nature. The better we understand these cycles and their dynamic interplay, the better we can help patients.