Single Record

Species: Clematis occidentalis [Clematis occidentalis var. grosseserrata] [Clematis grosseserrata] [Atragene grosseserrata]

Comments: If we credit voucher labels, Western blue clematis has been recorded several times, from both sides of the Valley: e.g., Wagon Wheel Gap (Mineral Co, 1952), east of the Great Sand Dunes (Saguache Co, 1975), Bishop Rock (Rio Grande Co, 1981), Penitente Canyon (Saguache Co, 1989). Most of these vouchers are labeled Clematis occidentalis or Clematis occidentalis var. grosseserrata. Ackerfield (2022) treats the taxon as Clematis grosseserrata and shows no locations in the Watershed. FNA treats it as C. occidentalis var. grosseserrata and shows a presence in Colorado as well as Utah, Wyoming, Montana, Idaho, Oregon, and Washington. BONAP includes it in C. occidentalis, with a distribution covering these states plus New Mexico, and then, disjunct, the Great Lakes region and Appalachia up to and including Maine. Allred et al. (2020) say, however, that all reports of C. occidentalis from New Mexico have turned out to be C. columbiana. Obviously, a review of herbarium specimens from the Watershed is needed. In iNaturalist, I have not seen a convincing observation of C. occidentalist from the Watershed, although a number are labeled as such. The confusion seems to lie in how the leaf shapes are interpreted.