Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by origin]
6. biological material
7. plant material
8. grass (plant material)

Anotations

Scope note:

Material derived from the long flat leaves of tall reedlike marsh plants of the genus Typha, used in making mats and chair seats, and since they swell when wet, leaves are used for caulking cracks in barrels and boats.