Tracheids form the only xylem conducting tissue of vascular plants other than angiosperms, some Gnetales, and a few ferns such as bracken.Compare vessel.

• 除了被子植物，买麻藤属的一些植物和少数蕨类如：欧洲蕨，其余的维管植物的木质部运输组织都仅包括管胞形式。