Panarctic Flora

912202 Heracleum lanatum Michx.

• Michx., Fl. Bor.-Amer. 1: 166 (1803). Holotype (P): Canada: Quebec, Chicoutoumé, leg. A. Michaux. - Heracleum sphondylium subsp. lanatum (Michx.) Á. Löve & D. Löve, Taxon 31: 350 (1982).
• Heracleum maximum Bartr., Travels Carolina: 344 (1791) nom. nud.? and illeg.?.
• Heracleum sphondylium subsp. montanum sensu Á. Löve & D. Löve (1975a), non (Schleich. ex Gaudin) Briq. in Schinz & R. Keller, Fl. Schweiz, ed. 2, 1: 372 (1905).

2n= 22 (2x). - Far East (N, S), Canada, U.S.A. - Several reports.

Geography: Amphi-Pacific - North American: ALA CAN.

Notes: Heracleum lanatum belongs to a widely circumscribed H. sphondylium group. The chromosome counts referred by Löve and Löve (1975a) must be checked against primary sources because the Löves at that time synonymized H. lanatum with the European and Russian H. sphondylium subsp. montanum as proposed by R.K. Brummitt. This synonymization has not been generally accepted. The Löves later combined a subspecies of H. sphondylium based on H. lanatum. We find H. lanatum evidently different from H. sphondylium.

Kartesz and Gandhi (1994: 442) argued that H. maximum Bartr. 1791 is a validly published name for this species in spite of some non-binomial names used in the work, and that this name should replace the later name H. lanatum. They cited supporting arguments by Merrill (1945) and Wilbur (1971). As Bartram's work is not "oppressed" by the Code (McNeill et al. 2006), the arguments of Kartesz and Gandhi are valid. However, Cronquist in Cronquist et al. (1977) assumed that the name "doubtless applies to the plant traditionally called H. lanatum" but that Bartram's comments are insufficient as a description and that H. maximum Bartr. therefore is invalid as a 'nomen nudum'. Kartesz and Gandhi did not refer to Cronquist's rejection. We provisionally retain the name H. lanatum for the Checklist.

Murray: Collections in arctic Alaska are associated with perennial springs.