treatments/Cirsium cymosum var. canovirens

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Cirsium cymosum   var. canovirens Sida. 21: 212. 2004.

Graygreen thistle


Larger heads 15–25 mm diam. Outer phyllaries usually much shorter than inner; glutinous ridge prominent, well developed, appearing dark brown on dry specimens. 2n = 34 (as C. canovirens).

Flowering spring–summer (Apr–Aug). grasslands , sagebrush steppe , pinyon-juniper woodlands , dry coniferous forests , roadsides ;600–2600 m;Calif.; Idaho; Mont.; Nev.; Oreg.; Wyo.;

Variety canovirens occurs from the dry mountains and valleys of eastern Oregon and the rain shadow slopes of the northern Sierra Nevada eastward across the northern Great Basin to Idaho, southern Montana, and western Wyoming. D. J. Keil and C. E. Turner (1993) recognized a polymorphic Cirsium canovirens that included C. subniveum (here treated as C. inamoenum). My subsequent investigations indicate that the merger of those taxa was erroneous, based in part on mis-identified specimens.