Late Boneset aka Eupatorium serotinum. The flowers and leaves are anti-inflammatory and anti-spasmodic. They have been used to treat flu, colds, coughs, prostate problems, diabetes, bronchitis, indigestion, fevers, joint pain, sinus problems, and more. The late great herbalist Tommie Bass used it in his cough syrup recipe. It is also an important plant for our pollinators which flock to it. There were so many pollinators around this plant, it had three green tree frogs hidden within its leaves.
UPDATED:
I shared this with someone:
"I use Late Boneset - Eupatorium serotinum as a tea or tincture when a virus hits. Late Boneset has many medicinal properties. Based on my research, the chemical profile shows it is an anti-inflammatory, anti-pyretic (fever reducer), immune system modulator, analgesic, diaphoretic (induces a sweat), antimicrobial (antibacterial, antiviral, antifungal), digestive aid, and it gives support to the lymphatic system. It is safe for most people in medicinal dosages (small amounts, short time-periods) which differs from a consumption amount (consumed regularly as a meal or beverage). From a chemical standpoint, Late Boneset is considered safer than Boneset because it has a lower risk of hepatotoxicity (do not consume it as a food source, but in small amounts for a short time as a medicine). Some sensitive people may have allergies to the sesquiterpene lactones of BOTH Boneset - Eupatorium perfoliatum. and Late Boneset, so one may want to follow the "edibility test protocol." Anyone allergic to plants in the Asteraceae family should avoid it. I am not a medical doctor. I am just sharing my research, usage, and personal experiences."