Trentepohlia abietina (Flotow) Hansgirg forms bright orange or orange-brown, soft, felt-like patches on tree bark.

The patches consist of rounded or swollen cells on the surface. Arising from these are erect and unilaterally- or irregularly-branched filaments of cylindrical cells.

Cells appear slightly orange in colour due to masking of the green chlorophyll by a carotenoid pigment.