Oolong teas are semi-oxidized (15 – 80%). The fresh leaves are laid out to wither, and then generally placed in horizontally turning baskets or manipulated by hand to begin oxidizing. After the leaves are deemed to be sufficiently oxidized, they are heated to stop the oxidation process. Some types (Tie Guan Yin, Tung Ting, Yuan Shen, Ali Shan) are then placed in cloth wrappers in which they are compressed on special rotating tables such that they roll up into little balls. Afterwards, they are again put into the rotating baskets. This tumbling process is repeated several times (up to thirty). For some types (Shui Xian, Wulong, Bao Zhong, Bai Hao, Feng Huang Dan Cong, & Da Hong Pao) the compression step is skipped, which produces long leaves with a spiral shape. The teas are finally dried and sorted by hand. Oolong teas combine the fresh, vegetal flavors and aromas of Green tea with the astringent, flowery aromas and flavors of Black tea.