I was recently asked about a plant used by the Hani People of Southern Yunnan, an area I have traveled a fair bit, thus these folks that I was a good person to ask. Here is some information I found about this plant for your reading enjoyment. For the record I am pretty sure I have seen this plant, though I was unable to find a photo in my collection.
There seems to be some nomenclature issues both with the botanical Latin and the Chinese, the latter of which is very common. The various different Chinese names are probably a little less critical for most of our readers, especially since this herb is not a commonly used herb in Chinese medicine. The 3 botanical Latin names I found were the initial name given to me in the question, Conoclinium coelestinum and in my research I also found the plant under 2 other names, Eupatorium adenophorum and Ageratina adenophora. However, in looking at the botany a little closer, it would seem that it is most likely Ageratina adenophora (Eupatorium adenophorum is no longer accepted) that is being referred to rather than Conoclinium coelestinum. It’s primary Chinese name is zi jing ze lan (紫茎泽兰), which means “purple stemmed ze lan” (ze lan is the Chinese name for a related or similar looking plant used in Chinese medicine known as Eupatorium japonicum). The English name given is “Crofton Weed.” I will revisit this information when I have more to say, but at the moment the information below should be understood to refer to Ageratina adenophora rather that Conoclinium coelestinum.
Here is some brief information about the Chinese uses of this plant. Flavor and nature: acrid, bitter, cool. Enters the urinary bladder, liver and kidney channels. Quickens blood and transforms stasis, quickens blood and regulates the menses. Courses wind and resolves the exterior [possibly diaphoretic], regulates the menses and quickens blood, transforms toxin and disperses swelling. Used to treat wind-heat “colds” [flu], damp diseases with fever, irregular menstruation, blocked [stopped] menstruation, flooding [menstruation], toxic swelling of unknown etiology, hot-toxic sores, rubella itching. Taken internally as decoction 6-15g daily, also used externally.