Wormwood leaves are gathered on a warm dry day in spring and summer when the plant is in flower and dried in the shade. In traditional Chinese medicine, they are considered to have bitter, pungent and warm properties and to be associated with the liver, spleen and kidney meridians. The leaves are used as an antiseptic, expectorant, febrifuge and styptic. The herb is considered to increase the blood supply to the pelvic region and stimulate menstruation, help treat infertility, dysmenorrhea, asthma and coughs. Another use is in moxibustion, a form of healing in which the herb is burned in cones or sticks or on the tip of an acupuncture needle. Boiling water can be poured onto the ground up leaves and used in a decoction, alone or with other substances, and the fresh leaf can be crushed and blended and a juice extracted. A volatile oil can be extracted from the leaves and used in the treatment of asthma and bronchitis for which purpose it is sprayed onto the back of the throat and brings rapid relief. The leaves have an antibacterial action and have been shown to be effective against Staphylococcus aureus, Bacillus dysenteriae, Bacillus subtilis, Bacillus typhi, Escherichia coli and Pseudomonas.
(Imformations are from WikipediaA : https://en.wikipedia.org/wiki/Artemisia_argyi)