SPECIES EVALUATION Frasera coloradensis, Priority 1. Frasera coloradensis (Rogers) D. M. Post (FRCO7). Colorado green gentian, Colorado frasera. CNHP G3 / S3, Track A FS: R2. -- G3 N3. CO S3. PSICC-Comanche Confi- Criteria Rank dence Rationale Sources of Information Doesn’t match any of the described ratings, distribution in R-2 doesn’t look like CNHP records, Johnston 1981, Naumann 1 any of the diagrams. One polygon on the R-2 map. Concepts such as “dispersal 1991, Weber and Wittmann 2001b. Distribution NA L among patches” and “population isolation” are not important for vascular . within R2 Species only occurs in four counties in southeastern Colorado. CNHP records, Johnston 1981, Naumann 2 1991, Weber and Wittmann 2001b. Distribution A H outside R2 Pollen viability is high; seed dispersal by a combination of wind, gravity, and Naumann 1991. 3 small animals. The limits on germination and population establishment are Dispersal C H apparently environmental, limestone substrate and climate. Capability Seeds are apparently highly viable; some were successfully germinated in a laboratory. Or Rating B. There are 25-30 occurrences, with population sizes ranging from 3 Naumann 1991. 4 to over 1,500 individuals (see graph on next page). Abundance in C M R2 Population sizes are stable over several decades. Naumann 1991, my observations. 5 Plants of Frasera coloradensis are not preferred by grazing animals, and under Population B H light to moderate grazing pressures cattle will not touch them. Under heavy grazing Trend in R2 pressures Frasera coloradensis could be clipped, but it would still not be preferred. Associated with surface outcrops of light-colored limestone, calcareous shale, or Naumann 1991, my observations. 6 calcareous sandstone, on gentle knolls, escarpments, ledges, knobs, roadcuts, Habitat Trend B H streamcuts, or fault scarps. These habitats have been stable for several decades. in R2 Or rating C. These habitats are somewhat vulnerable, but plants of Frasera Naumann 1991, my observations. 7 coloradensis often occur in microsites where there is not much grass, so these sites Habitat B M would not be often visited by cattle under moderate to light grazing pressures. Vulnerability or Grazing by cattle is the major disturbance factor in these habitats; on the National Modification Grassland, this is managed at a moderately low level, but it may or may not be so on private lands. High reproductive rates have been documented, and the species does not seem to Naumann 1991, my observations. 8 be susceptible to disease, predation, or competition. Life History and C M Demographics

1 SPECIES EVALUATION National Forests in the Rocky Mountain Region where species is KNOWN (K) or LIKELY (L)* to occur: *. Likely is defined as more likely to occur than not occur on the National Forest or Grassland. This generally can be thought of as having a 50% chance or greater of appearing on NFS lands. COLORADO NF/NG K L K L K L Arapaho-Roosevelt NF NEBRASKA NF/NG WYOMING NF/NG White River NF Samuel R. McKelvie NF Shoshone NF Routt NF Halsey NF Bighorn NF Grand Mesa Uncompahgre Gunnison NF Nebraska NF Black Hills NF San Juan NF Ogalala NG Medicine Bow NF Rio Grande NF SOUTH DAKOTA NF/NG Thunder Basin NG Pike-San Isabel NF Black Hills NF KANSAS NF/NG Comanche NG K Buffalo Gap NG Cimarron NG Pawnee NG Ft. Pierre NG

Taxonomy. Frasera coloradensis is accepted as a species by all botanists; it was originally called 10000 coloradensis when first described, and a few botanists would prefer that name. Discussion. Frasera coloradensis is an endemic 1000 species, but it seems fairly secure. Populations and habitats have apparently been stable for some time, and there are no documented threats. There does not seem to be a viability concern with Frasera coloradensis. 100

References

Harrington, Harold D. 1954. Manual of the plants of Population (logarithmic) 10 Colorado: For the identification of the ferns and flowering plants of the state. Denver, CO: Sage Books. 666 pp. 1 Johnston, Barry C.; and William Harmon. 1981. Status 1 10 100 report: Frasera coloradensis (Rogers) D. M. Post. Lakewood, CO: USDA Forest Service, Rocky Area, acres (logarithmic) Mountain Region, 27 pp. Naumann, Tamara. 1991. Status report for Frasera coloradensis. Denver, CO: Colorado Natural Areas Program, 43 pp. + Maps + Appendix. Post, Douglas M. 1958. Studies in : I. Nodal anatomy of Frasera and Swertia perennis. Botanical Gazette 120(1):1-14. Rogers, C. M. 1949. A new Swertia from Colorado. Madroño 10:108-110. Spackman, Susan; Bill Jennings; Janet Coles; Carol Dawson; Mark Minton; Andrew Kratz; Carol Spurrier; Christopher S. Johnson; and Mike Barry. 1999. Colorado rare field guide. http://ndis.nrel.colostate.edu/ndis/rareplants/cover.html, last updated March 1, 1999. Weber, William A.; and Ronald C. Wittmann. 2000. Catalog of the Colorado flora: A biodiversity baseline. Boulder, CO: University of Colorado Museum. Revised March 11, 2000. http://www.colorado.edu/CUMUSEUM/research/botany/Catalog/Catalog.htm, downloaded September, 2002. Weber, William A.; and Ronald C. Wittmann. 2001b. Colorado flora: Eastern Slope, Third Edition. Boulder, CO: University Press of Colorado. 521 pp.

Author and date: Barry C. Johnston, Botanist, Grand Mesa-Uncompahgre-Gunnison National Forests, 216 N. Colorado St., Gunnison, CO 81230-2197. (970) 642-4467. [email protected]. Last modified September 26, 2002.

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