bull kelp n Also bull-head kelp [The name bull kelp appears somewhat earlier in reference to a genus of large brown seaweeds (Durvillaea) of the southern hemisphere. The large spherical pneumatocysts of Nereocystis luetkeanus may have inspired the expansion to bull-head kelp, but as Durvillaea spp lack them entirely, this does not explain the older form of the name.]
A large brown seaweed (Nereocystis luetkeanus) of the Pacific coast.
1875 Nature (London) 12.166 AK, The “bull-head kelp” (Nereocystis?) is excessively abundant in the Aleutians, and extends north to Nunivak and the Pribiloff Islands. 1895 Auk 12.105 sCA, As a rule they [=fulmars] prefer to obtain their food in open water where they are much oftener seen than along the immense beds of kelp (Macrocystis pyrifera) and ‘bull kelp’ (Nerecystis lutkena) that fringe the shores for miles along the southern coast. 1913 Jrl. Franklin Inst. 176.357 Pacific, It [=giant kelp] is sometimes known locally as ribbon kelp, sometimes as bull kelp. 1931 Corona Daily Independent (CA) 17 Apr /4 (newspaperarchive.com), The location of this sporting event was in the “bull kelp” bed about twelve miles off shore. 1940 Fairbanks Daily News–Miner (AK) 6 June 8/4, Mustard pickles and sweet pickles made from the ordinary kelp known as bull kelp are the specialty of Mrs. Doc Silvers of Dundas Bay. 1982 Mod. Maturity June–July 51 cwCA, But look carefully; it’s easy to mistake the dark-brown floats of bull kelp for the heads of sea otters or harbor seals. 2007 in 2016 DARE File—Internet, We drew floorplans for our imaginary houses. . . Bullhead kelp were our children, complete with stringy hair. 2012 Walla Walla Union–Bulletin (WA) 8 Oct sec A 4/4, It disappears . . then slowly pops up for a closer look—a head of bull kelp.