Albizia julibrissin (合欢) is a commonly used herb in Chinese medicine to calm the spirit. Both the flower and bark are used, and they are both used to calm the spirit, but they also have some differences. The bark has a longer history of use, first being mentioned in the Ben Cao Jing and then later being found in Perscriptions Worth a Thousand Pieces of Gold, by Sun Si-miao, who has the exact same entry as the Ben Cao Jing.
The Ben Cao Jing says the bark (合欢皮) is sweet and neutral. It quiets the five viscera and the heart-mind. Brings happiness without anxiety and taken long-term makes the body light, brightens the eyes, and reduces desires. (I’m not exactly sure about this last translation, open to suggestions.)
The Grand Dictionary of Chinese Medicinals says it is sweet, neutral and enters the heart and liver channels. It quiets the spirit and resolves depression, harmonizes the blood and disperses welling-abscesses. It treats disquieted heart spirit, anxiety depression, sleepnessless, lung welling-abscess, welling-abscess swelling, and injuries from knocks and falls.
The flower (合欢花) first appeared in the Augmented Materia Medica (1116 CE), the Grand Dictionary of Chinese Medicinals says it is sweet, bitter, and neutral and enters the heart and liver channels. It soothes depression, quiets the spirit, rectifies qi, brightens the eyes, and quickens the network vessels. It is used to treat anxiety depression with sleeplessness, disquieted heart spirit, forgetfulness, chest distention with torpid intake, wind-fire eye disease, lumbar pain, and pain from knocks and falls.
This plant is common in many parts of North America as well as China. Anybody in Europe know if it has been planted there? I have gathered it in Oregon, California, and Massachusetts. I generally prefer the flowers over the bark for most conditions, but quality can be an issue, so it is important to be sure you are getting good quality, or harvesting it yourself. The fresh plant tincture is delightful and has been a staple in many preparations I have made for patients for years.
In his Shen Nong Ben Cao Jing Shu (神农本草经疏) from 1625 Miao Xi-yong has a few interesting things to say about the bark of albizia.
Albizia receives its qi from the earth to grow, therefore its flavor is sweet, its qi is even, and it is without toxins. It enters the hand shao-yin and foot tai-yin channels. Earth is the mother of all living things. Albizia nourishes the five viscera, the heart is the sovereign and governing official, [it is] the root of harmony in the body. If the spleen is vacuous then the five viscera are restless, [if the] heart qi is restless then one will encounter abundant depression. Sweet governs boosting the spleen, the spleen is, in fact, the nature of quietness within the five viscera. Sweet can slow, [if the] heart qi is relaxed, then the spirit light will itself be free and joyous and without worry, [if the] spirit light is free and smooth, then perception will shine and the person will be omnipresent, therefore desires will all be satisfied!