The "Oo-yomogi" (Artemisia montana) belongs to Asteraceae (the Aster family). It is a perennial herb that is distributed northward from Kinki district of Honshu to Hokkaido, as well as the Korean Peninsula, central-eastern China and Sakhalin. This herb grows in mountains on the Japan Sea side and can reach 1.5-2 m in height. The leaves are deep pinnately and opposite with winged petioles. They are larger than the Mugwort's and covered with long white wooly hairs on the abaxial sides. The panicles are borne on the terminal stems and the inconspicuous flowers bloom from August to September. The young leaves are used for herb mochi after boiling and the wooly hairs are used for moxa. It is called "山地蒿" (shan di hao) in Chinese.
In Korean, it's called "san-ssuk" (산쑥). This is a compound word consisting of "mountain" (san: 산) + "Japanese mugwort" (ssuk: 쑥).
Photos 19-21 show the parasitic insect "Cottony cushion scale" (Phenacoccus pergandei).