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From "Shennong Bencao Jing"
1. "Wu Pu Ben Cao": Qin Da Cha Yao, grows in Nan Yue Mountain or Yi Zhou. The leaves are like kudzu, with red stems, as large as arrows, and the square roots are yellow. It may also grow in Dong Ye of Hui Ji. Harvest in January.
2. "Southern Plants and Trees": Ye Ge, a poisonous plant, grows as a vine. The leaves are glossy and thick, resembling basil. It is also known as Hu Man Cao.
3. "Lei Gong Pao Zhi Lun": Da Cha Yao is effective in treating malignant ulcers. The essence of this plant is deadly. After harvesting, it should be crushed and the natural juice should be mixed into an ointment. Do not mistake it for food.
4. "Bie Lu": Da Cha Yao, when broken, emits green smoke, known as Gu Huo. It is very hot and should not be added to soup. It grows in Fu Gao Mountain Valley and Dong Ye of Hui Ji.
5. Tao Hongjing: The "Wu Fu" text also mentions that Da Cha Yao is wild kudzu, so called because it hooks onto the throat when consumed. Some say "hook" is pronounced as "wan" and it hooks onto the intestines and strangles them. However, these are two different things. Wild kudzu refers to the root, which resembles peony and is also poisonous. Birds cannot gather on it. People nowadays mix it with ointment and take it without any worries. Da Cha Yao is actually a different plant, with leaves resembling Huang Jing and purple stems. When the flower blooms, it is yellow, similar to Huang Jing, hence it is considered a killer. Some say Da Cha Yao is Ranunculus, but the source and later explanations are different, so it is not clear what it is.
6. "Tang Ben Cao": Wild kudzu grows south of Gui Zhou, and it can be found everywhere in villages and towns. The local people call it Da Cha Yao. It is also called Wei Miao Da Cha Yao, and the root is called wild kudzu. It grows as a vine. Eating its leaves can cause death, but when eaten with watercress, there is no harm. Dripping the juice of wild kudzu on the leaves can cause immediate death, as it is lethal in this way.
7. "Ben Cao Gang Mu Shi Yi": When people eat the leaves of wild kudzu and drink cold water, they die instantly. The cold water activates the poison. The people of the south eat watercress first and then consume wild kudzu, and both substances neutralize each other, preventing harm. Dripping the juice of wild kudzu on watercress can cause instant death, demonstrating their mutual lethal effect.
8. "Ling Biao Lu Yi": Wild kudzu is a poisonous plant, also known as Hu Man Cao. If mistakenly consumed, it can be counteracted with the blood of a mountain goat.
9. "Meng Xi Bi Tan": Da Cha Yao, also known as wild kudzu in "Ben Cao". It has many medicinal uses, and there are various interpretations. Some say it can be used as medicine, while others say it is highly toxic and can cause death when eaten. When I was in Fujian, local people used wild kudzu to commit suicide or accidentally consume it, and even half a leaf in the mouth would result in death. Drinking flowing water with it is even more lethal, often resulting in death shortly after drinking. I once had someone bring me a plant to observe. It grows as a vine, similar to kudzu. The stem is red and thick, resembling a heron's knee. The leaves are round with pointed tips, like apricot leaves, but thicker like persimmon leaves. Three leaves form one branch, similar to mung bean leaves. Leaves grow between the nodes, all facing each other. The flowers are small and yellow, similar to fennel flowers, growing between the nodes and leaves.
10. "Gang Mu": Da Cha Yao, although called wild kudzu, is not the wild variety of kudzu. It is also called Ye Ge. Wang Chong's "Lun Heng" states that "Ye" is the name of a place in the southeast, which is widely accepted. People in Guangdong call it Hu Man Cao, also known as Duan Chang Cao. When it enters the stomach of humans or animals, it sticks to the intestines and turns black and rotten after half a day, earning it the name "Rotten Intestine Grass". People in Yuezhou call it Huang Teng. According to the "Ling Nan Wei Sheng Fang", when one leaf is consumed, it causes blood to flow out of every pore, resulting in death. Li Shizhen also mentions that the Huang Teng mentioned is the root of wild kudzu. He also says that the people of Yunnan call it Huo Ba Hua because its flowers are red and it has a hot nature like fire. In Yuezhou, it is called Huang Teng. According to the "Ling Nan Wei Sheng Fang", the flowers are yellow when they grow in Lingnan, but red when they grow in southern Yunnan.
11. "Zhi Wu Ming Shi Tu Kao": Since ancient times, there has been no mention of Da Cha Yao and Huang Jing being the same, nor has it been specified as Duan Chang Cao. "Shen Nong Ben Cao Jing" calls it Ye Ge. Ye Ge has been considered by later generations to be Duan Chang Cao. The poisonous plant Duan Chang Cao is not the only one of its kind. "Southern Plants and Trees" mentions Ye Ge, also known as Hu Man Cao, but does not say it is Da Cha Yao. Since Su Gong, people have considered the sprouts as Da Cha Yao and the roots as wild kudzu, strongly criticizing Tao Hongjing's explanation, claiming that the leaves resemble persimmons and malva nuts, which would make it the large-leaved Duan Chang Cao in Lingnan today. Shen Cunzhong's "Yao Yi" also considers Da Cha Yao to be Duan Chang Cao, but also says that Duan Chang Cao is an extremely poisonous plant that is not used medicinally. It seems that the source of "Ben Cao" is a different plant, not Da Cha Yao. "Wu Pu Ben Cao" mentions that Da Cha Yao may come from Yi Zhou. After the Bi Ji and Jin Ma plants were lost to the southern court since the Kaiyuan period, it is understandable that Su Gong and others were not familiar with the Da Cha Yao from Yi Zhou. When I went to Yunnan, I sent someone to collect plants from the mountains and obtained two plants similar to Huang Jing and Yu Zhu. The labels indicated that they were Da Cha Yao and Han Da Cha Yao. Da Cha Yao has bamboo-like leaves, similar to Huang Jing but smaller. The leaves grow on one side, and the flowers and fruits grow on the other side. When discarded, they are still alive. It is likely that this is the "ground essence" mentioned by Lei Xu, also known as Pian Jing. People say it has a hook-like shape and is highly poisonous. Therefore, the name "hook" is not because the leaves resemble hooks. The Pian Jing is slightly less toxic but also has a peculiar shape. Da Cha Yao, a low-grade herb according to "Shen Nong Ben Cao Jing", is believed to be the same as Duan Chang Cao, the current Lingnan large-leaved Duan Chang Cao. Inquiring with people from Fujian and Guangdong, there are said to be two sizes of Duan Chang Cao. The larger ones have leaves similar to night-blooming jasmine and grow as vines, while the smaller ones have leaves similar to horse orchids and are even more fierce. Li Shizhen's mentioned Huang Teng is actually the root of Miao Cao. He also mentions that the people of Yunnan call it Huo Ba Hua. This is probably the plant described in "Qian Shu" as having red flowers like mulberries. They are all toxic plants, not just one species.
