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*Yunnan Zhi* records: It is produced in the rock cliffs near the Pudu River in Luquan Prefecture. Those with a purplish-red color are of the best quality.
It treats stomach heat and benefits deficiency emaciation (weakness and thinness due to deficiency).

*Benshu Jing Shu* states: There are two types of Chai Hu (Bupleuri Radix) used in common practice: one type is white with yellow hues and large, named Yin Chai Hu (Stellariae Radix), which is specifically used to treat consumptive fever and bone-steaming tidal fever; the other type is slightly black and slender, used for releasing the exterior and dispersing pathogens. *Shennong Bencao Jing* does not mention this distinction between two types, nor does it differentiate their functions, but merely states that those from Yinzhou are the best, indicating that they are superior for releasing the exterior and dispersing, rather than being medicines for treating deficiency heat, which is clear.

*Benshu Hui* records: Chai Hu produced in Yinzhou and Xiazhou has a slightly white color and soft texture, known as Yin Chai Hu. It is used to treat bone-steaming tidal fever caused by consumptive weakness. After soaking in the urine of a yellow ox overnight and drying in the sun, it proves effective for treating consumptive fever. *Benjing Fengyuan* states: Yin Chai Hu from Yinzhou is good. Currently, those produced in Wuyuan City, Yan'an Prefecture, are over a chi long, fat, white, and soft; those produced in the north are soft like Qian Hu (Peucedani Radix) and are now called Bei Chai Hu (Northern Bupleuri Radix). Do not let them come into contact with fire, otherwise they will lose efficacy.

*Baicao Jing* states: It comes from Ningxia Town, Shaanxi. The leaves are harvested in February, named Yun Hao. They are over a chi long, slightly white, and weaker in potency than Chai Hu.

*Yaobian* states: Yin Chai Hu comes from Ningxia Town. Its shape resembles Huang Lian (Coptidis Rhizoma), containing clusters resembling Gan Cao (Glycyrrhizae Radix et Rhizoma); do not confuse it with others.

Weng Youliang states: Yin Chai Hu from Yinzhou is of fine quality and has two types. One can distinguish it if its shape resembles a rat's tail and is equal in size to Qian Hu. Investigating further, Qian Hu and Chai Hu are similar, with those from the northwest being superior. Since their shapes are alike, one should take the Chai Hu from Gucheng, Huguang, as the standard. Current Yin Chai Hu varies in thickness, some as thick as a thumb and several chi long, neither resembling a rat's tail nor looking like Qian Hu. This does not align with the materia medica, making it difficult to distinguish the two uses in treatment, and ultimately not accurate; users should examine carefully.

Jin Yucheng states: Chai Hu from Yinzhou is soft and white. Those produced in the north are also white, and people currently use them to pass off as Bai Tou Weng (Pulsatillae Radix); this kind can also be called Yin Chai Hu. "Yin" likely refers to color, not place, just as the white variety of Jin Yin Hua (Lonicerae Japonicae Flos) is called Yin Hua. Yin Chai Hu originally had distinctions between western and northern production, so it is not necessary to strictly define only those from Yinzhou and Xiazhou as Yin Chai Hu. However, those from the west are superior for medicinal use.

Note: *Bencao Gangmu* notes that Yin Chai Hu from Yinzhou and Xiazhou is superior, unaware that current Chai Hu usage distinguishes between Bei Chai Hu (Northern Bupleuri Radix) and Nan Chai Hu (Southern Bupleuri Radix). Northern varieties are soft like Qian Hu, while southern varieties are hard and unsuitable for use. Furthermore, although Yin Chai Hu can release the exterior, it is not as harsh as Chai Hu; *Bencao Gangmu* mixes them without analysis.

The taste is sweet and slightly cold, non-toxic. It enters the Foot Yangming Stomach Meridian and Foot Shaoyin Kidney Meridian. Its nature is not very close to Shi Hu (Dendrobii Caulis); it not only clears heat but also cools blood. In *Tai Ping Hui Min He Ji Ju Fang*, it is used to treat bleeding from various parts above and below the body, such as in Long Nao Ji Su Wan. Whenever entering formulas for treating consumptive diseases, only those from Yinzhou are suitable. Bei Chai Hu ascends and agitates deficient yang, causing fever, wheezing, and coughing, leaving no peace; how can one fail to distinguish and mix them indiscriminately? Note: Under the entry for Chai Hu, *Shennong Bencao Jing* mentions pushing out the old and generating the new, brightening the eyes, and benefiting essence; these all refer to those from Yinzhou and Xiazhou. This is beyond the capability of Bei Chai Hu.

Zhou Yishi states: For heat located in the marrow, nothing can treat it better than Yin Chai Hu.
It treats consumptive disease with muscle fever, bone-steaming toxic heat, heat emanating from the marrow, and pediatric five-type malnutrition with emaciating fever.