PL no. 



Half-sections of Horsetail Stems. 



1. Field Horsetail ; 2. Blunt-topped Horsetail ; 3. Great Horsetail : 4. Wood Horsetail ; 

 5. Marsh Horsetail ; 6. Mud Horsetail : 7. Dutch Rush ; 8. Variegated Horsetail. 



