1.药材鉴别药材呈圆锥形,略扭曲,直径1~3 cm,长8~25 cm。表面棕黄色或深黄色,表面具稀疏的疣状细根痕,上部较粗糙,有扭曲的纵皱或不规则的网纹,下部有顺纹和细皱。人工栽培品皱纹较细腻,质硬而脆,易折断,老根可见腐朽的木部外露。断面黄色,中心红棕色;老根中心枯朽状或中空,暗棕色或棕黑色。本品遇冷水或遇潮 1. Identification of medicinal herbs conical, slightly twisted, diameter 1 ~ 3 cm, length 8 ~ 25 cm. The surface of the yellowish brown or dark yellow, the surface is sparse verrucous fine root marks, the upper rough, warped longitudinal wrinkles or irregular texture, the lower part of the pattern and fine wrinkles. Cultivated wrinkles more delicate, hard and brittle, easy to break, the old roots can be seen decadent wood exposed. Section yellow, reddish brown center; old roots dry or hollow center, dark brown or brown-black. This product is cold or wet case