Description: The medium brown to almost black thallus is coarse with cylindrical to slightly flattened branches arranged in an alternate pattern and a discoidal holdfast. The main axis is stiff and up to 5 mm (0.2 in) wide, and the whole individual can be up to 2 m (6.5 ft) tall. This species is low in sulfuric acid so it does not self-destruct like other species of >em>Desmarestia. Habitat: This perennial is found on rock (including cobble) in the low intertidal to subtidal zones from protected to semi-exposed habitats. Similar taxa: Chordaria.