Corkscrew willow tree xylem. Scanning electron micrograph (SEM) of a cross section through the branch of the Corkscrew Willow Tree (Salix matsudana 'Tortuosa'). This micrograph shows the xylem vascular tissue for transporting water and mineral nutrients through the roots to the main body of the tree. This deciduous tree is also known as the Tortuosa or Dragon's Claw Willow because of its contorted and twisted branches, leaves and twigs. Magnification x1850 (x455 at 10cm wide).