Ampelopsis grossedentata

Ampelopsis grossedentata, commonly known as moyeam, is a species of plant in the Vitaceae family. It is mainly distributed in central and southern China, but can also be found in some southeast Asian countries. The leaves and stems are used to make a herbal tea called 'moyeam'. The product has been popular in China for generations and is now consumed in some other countries. The English name 'moyeam' comes from the Chinese name '茅岩莓' (Pinyin:máo yán méi). Most moyeam is grown in Zhangjiajie, a mountainous region in Hunan Province in central China. Moyeam germinates in the spring and fades in the autumn. There is no significant difference between its primary and secondary roots. Stems and leaves are glabrous, and stem diameter is about 0.2–0.4 cm (0.079–0.157 in). The largest annual production is in early summer, followed by autumn. Average annual growth is 0.7–0.8 m (2.3–2.6 ft). The dorsal leaves are gray in the spring. Leaflets are thin, papery, or herbaceous, long, narrow, oblong, oval or needle-shaped. Their margins are coarsely toothed. Young stems and leaves are light reddish purple. The method of processing this plant was developed by the Tujia minority group 600 years ago. It involves plucking, withering, rolling, and fermenting the leaves. The fresh leaves should be withered within five hours to avoid oxidization and loss of nutrients. The rolling step produces its distinctive 'white frost' color and enhances the flavor. Unoxidized 'white' moyeam is also produced, but the more demanding production process for white moyeam (similar to the method by which green tea is produced) makes it more expensive than traditional moyeam. Its distinctive taste is slightly bitter with a strongly sweet aftertaste; the slightly grassy flavor is somewhat different from other common teas in China.