WhatsInTCM

Usnea (Fine filaments intertwined in clumps, grayish-green, with segmental cracks)

[Naming]

Usnea

[Source]

Shen Nong’s Herbal Classic of Materia Medica, Middle Grade‧Usnea

[Frequency of Use]

F

[Botanical Origin]

It is the filamentous thallus of Usnea plants, specifically Usnea longissima Ach. and Usnea diffracta Vain.

[Characteristics]

Fine filaments intertwined in clumps, 10-40 cm long, with dichotomous branching. The base of the main branch is relatively thick, with a diameter of 0.8-1.5 mm. The branches become more numerous and finer closer to the front end. The surface is grayish-green or yellowish-green, with numerous obvious segmental cracks. The cross-section has a linear, strong central axis with elasticity, and an algal ring outside it. It has a slight odor and a slightly sweet taste.

[Category]

Fungi and Algae