Description: Thallus has a stiff, woody stipe to 1.5 m (60 in.) long and blade-like sporophylls attached along the flattened distal margins of the stipe, which usually terminates in a small, smooth blade with a faint midrib. This tough kelp can reach 2.3 m (7.5 ft) tall. Habitat: It is a long-lived perennial, usually found only on rock, including cobble, in the subtidal zone (7-20 m, 23-66 ft) of more exposed coasts.