Juncus effusus

This record represents the narrow concept of Juncus effusus not including six varieties that have been elevated to species following Kirschner (2002) and Zika (2013). The narrow concept recognizes four subspecies: J. effusus ssp. austrocalifornicus, J. effusus ssp. effusus, J. effusus ssp. pacificus, and J. effusus ssp. solutus. There is an additional subspecies not occurring in North America: J. effusus ssp. laxus (Kirschner 2002). The six elevated varieties include J. hesperius (previously J. effusus var. brunneus), J. conglomeratus (previously J. effusus var. conglomeratus), J. decipiens (previously J. effusus var. decipiens), J. exiguus (previously J. effusus var. exiguus), J. laccatus (previously J. effusus var. gracilis), and J. pylaei (previously Juncus effusus var. pylaei). In contrast, Kartesz (1994, 1999) recognized nine varieties of J. effusus, and FNA (2000, vol. 22) did not recognize subspecific taxa of J. effusus, noting, "The Juncus effusus complex has been variously recognized as containing several species or a single species with numerous infraspecific taxa. Unfortunately, North American treatments have dealt primarily with taxa in either the eastern or western portions of the continent. In considering the continent as a whole, little sense can be made of these treatments."