Saussurea weberi
Author: Hulten


Weber saussurea


Asteraceae (Sunflower Family)

Close up of Saussurea weberi by Susan Spackman Panjabi.
Click image to enlarge.

Close up of Saussurea weberi by Susan Spackman Panjabi.
Click image to enlarge.
Close up of Saussurea weberi by Susan Spackman Panjabi.
Click image to enlarge.
Close up of Saussurea weberi by David Elin.
Click image to enlarge.

Ranks and Status

Global rank: G2G3
State rank: S2
Federal protection status: None
State protection status: None

[+] Description and Phenology

Saussurea weberi by Janet Wingate
Click image to enlarge.

General description: Saussurea weberi is a dwarf perennial herb that is 5-20 cm high, arising from a woody rootstock. The lance-shaped leaf blades are coarsely toothed, up to 8 cm long, and have a broad petiole. The alternate leaves are crowded on the stem, reduced, and lacking petioles towards the top. Herbage is covered with long, tangled hairs when young but becomes glabrous with age. The purple flowering heads are borne in a dense cluster subtended by leaves at the top of the stem. The broad involucral bracts of the heads have rounded tips and are 11-15 mm long. All of the flowers are tubular (disk flowers); ray flowers are absent. The achene has long plumose pappus bristles.

Look Alikes: None, this species is the only member of this genus to occur in Colorado. It is similar to S. densa of farther north but the two do not co-occur in Colorado.

Phenology: Flowers late July through August (Colorado Natural Heritage Program occurrence records).

[+] Herbarium Photos

Images of Saussurea weberi housed at the Colorado State University Herbarium.

Click image to enlarge.

Click image to enlarge.

Click image to enlarge.

Click image to enlarge.

[+] Habitat

Habitat of Saussurea weberi by Susan Spackman Panjabi.
Click image to enlarge.

In Colorado, this alpine species is found on wet ledges, in dry alpine turf, gravelly tundra, and scree slopes; exposed sites with poorly developed soils derived from Leadville Limestone and Manitou Dolomite (O'Kane 1988, Spackman et al. 1997). Sites can be perennially wet to quite dry. Associated species include Betula glandulosa, Salix planifolia, Luzula spicata, Danthonia intermedia, Rydbergia grandiflora, Thalictrum alpinum, Potentilla uniflora, Paronychia pulvinata, Draba crassa, Salix brachycarpa, Carex nova, Salix reticulata, Deschampsia cespitosa, Gentianella acuta, Carex rupestris, Trifolium parryi, Zigadenus elegans, Potentilla subjuga, Packera cana, Calamagrostis purpurascens, Cerastium strictum, Erigeron pinnatisectus, Phleum commutatum, Oxytropis viscida, Oligosporus groenlandicus, Bistorta vivipara, Rhodiola integrifolia, Hymenoxis grandiflorum, Trifolium dasyphyllum, Gentian algida, Pedicularis groenlandica, Zigadenus elegans, Caltha leptosepala, Juncus drummondii, Luzula spicata and Gentiana prostrata. 

Elevation Range: 10,938 - 14,262 feet (3,334 - 4,347 meters)

[+] Distribution

Distribution of Saussurea weberi in Colorado according to mapped land ownership/management boundaries (CNHP 2017, COMaP).
Click image to enlarge.

Distribution of Saussurea weberi in Colorado.
Click image to enlarge.

Colorado endemic: No
Global range: Regional endemic of southwest Montana, northwest Wyoming, and central Colorado (USDA NRCS 2017).
State range: Known from Custer, Lake, Park, and Summit counties in Colorado. Also known from Wyoming and Montana.

[+] Threats and Management Issues

Summary results of an analysis of the status of Saussurea weberi based on several ranking factors. This species was concluded to be "Effectively Conserved”. From Rondeau et al. 2011. etc
Click image to enlarge.

The primary threat at this time is considered to be mining (Rondeau et al. 2011). It is not known if all of the occurrences are or are not threatened by these activities. Saussurea weberi is thought to have a naturally limited range and is not known to have suffered significant population or habitat loss as a result of human activities. However, distribution information may not be complete and little is known about the basic ecology and biology or environmental requirements of S. weberi, and there are limited data regarding population trends. The species' rarity is likely due in part to discontinuous habitat availability across a limited geographic range and restricted habitat requirements, which are also responsible for its inherent ecological and geographic vulnerability. Human activities may pose threats to individual occurrences and, if not properly managed, may adversely impact the long-term survival of the species. Saussurea weberi is vulnerable to management practices that affect the quality and quantity of its habitat. Rangewide threats to Saussurea weberi are due mainly to potential climate change and environmental stochasticity. Ultimately, warming associated with global climate change may pose the greatest threat to this and other alpine species. Human-related threats are generally low across the range of S. weberi and in most of Region 2, although some of the occurrences on USFS lands in Colorado may be at greater risk, as are the two occurrences on private land in Colorado. Primary threats include off-road vehicle (ORV) use, mining activities (including associated road and other mine-related construction), and other construction, including residential development on private land. All of the occurrences in Wyoming and Montana are within designated wilderness areas, which greatly reduce the potential for damage from ORVs, since motorized vehicles are not permitted in wilderness areas. Activities such as livestock and non-motorized recreational activities currently pose minor threats, as many occurrences are not in active grazing allotments and most occurrences are not in areas that favor grazing. Livestock and non-motorized recreational activities may potentially pose more serious threats in the future if management policies change or the intensity of use increases. Invasive weeds do not appear to pose a threat at present. Management-related threats to USFS Region 2 occurrences are generally low, but include potential for damage by ORVs, mining activities and associated road construction, livestock trampling and possibly herbivory, and non-motorized recreational activities such as hiking (Glisson 2004).

[+] References

    • Achuff, P. L. and L. S. Roe. 1992. Botanical survey of the Goat Flat proposed Research Natural Area, Deerlodge National Forest. Unpublished report to the Deerlodge National Forest. Montana Natural Heritage Program, Helena, MT. 31 pp.
    • Colorado Native Plant Society. 1989. Rare plants of Colorado. Rocky Mountain Nature Association, Colorado Native Plant Society, Estes Park, Colorado. 73 pp.
    • Colorado Natural Heritage Program and the Geospatial Centroid. 2017. The Colorado Ownership and Protection Map (COMaP). Colorado State University, Ft. Collins, CO.
    • Dorn, R. D. 2001. Vascular Plants of Wyoming. 3rd edition. Mountain West Publishing. Cheyenne, Wyoming. 412 pp.
    • Dorn, R.D. 1984. Vascular plants of Montana. Mountain West Publishing, Cheyenne, Wyoming. 276 pp.
    • Fertig, W. 2000. Saussurea weberi state species abstract. Wyoming Natural Diversity Database summaries posted for plant species of special concern [pdf files]. Available: http://www.uwyo.edu/wyndd/ University of Wyoming, Laramie.
    • Fertig, W., C. Refsdal, and J. Whipple. 1994. Wyoming rare plant field guide. Wyoming Rare Plant Technical Committee, Cheyenne. No pagination.
    • Flora of North America Editorial Committee. 2006. Flora of North America North of Mexico. Vol. 19. Magnoliophyta: Asteridae, part 6: Asteraceae, part 1. Oxford University Press, New York. xxiv + 579 pp.
    • Glisson, B. 2004. Saussurea weberi Hultén (Weber's saw-wort): a technical conservation assessment. USDA Forest Service, Rocky Mountain Region. Online. Available: http://www.fs.fed.us/r2/projects/scp/assessments/saussureaweberi.pdf (Accessed 2006).
    • Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
    • Lackschewitz, K. H. 1976. Montana mountain flora: new records. Madrono 23:360-362.
    • Marriott, H. 1991. Field survey for Androsace chamaejasme var. carinata and Saussurea weberi, Northwest Wind River Range, Wyoming. Unpublished report to the Bridger-Teton National Forest. Wyoming Natural Diversity Database, The Nature Conservancy. 21 pp.
    • Montana Natural Heritage Program. Montana Plant Field Guide. Online. Available: http://mtnhp.org/plants/plantguide.asp (Accessed 2006).
    • Neely, B., S. Panjabi, E. Lane, P. Lewis, C. Dawson, A. Kratz, B. Kurzel, T. Hogan, J. Handwerk, S. Krishnan, J. Neale, and N. Ripley. 2009. Colorado Rare Plant Conservation Strategy, Developed by the Colorado Rare Plant conservation Initiative. The Nature Conservancy, Boulder, Colorado, 117 pp.
    • O'Kane, S. L. 1988. Colorado's Rare Flora. Great Basin Naturalist. 48(4):434-484.
    • Rondeau, R., K. Decker, J. Handwerk, J. Siemers, L. Grunau, and C. Pague. 2011. The state of Colorado's biodiversity 2011. Prepared for The Nature Conservancy. Colorado Natural Heritage Program, Colorado State University, Fort Collins, Colorado.
    • Spackman, S., B. Jennings, J. Coles, C. Dawson, M. Minton, A. Kratz, and C. Spurrier. 1997. Colorado rare plant field guide. Prepared for Bureau of Land Management, U.S. Forest Service and U.S. Fish and Wildlife Service by Colorado Natural Heritage Program.
    • Strickler, D. 1990. Alpine Wildflowers. The Flower Press, Columbia Falls, Montana. 112 pp.
    • U.S. Forest Service, Intermountain Region (USFS). 1990. Idaho and Wyoming endangered and sensitive plant field guide. U.S. Forest Service, Intermountain Region, Ogden, UT. 192 pp.
    • USDA, Natural Resources Conservation Service, PLANTS Database [USDA PLANTS]. http://plants.usda.gov/. Accessed 2017.
    • Watson, T. J. and K. H. Lackschewitz. 1980. The genus Saussurea (Asteraceae-Cynareae) in Montana. Northwest Science 54(2):106-108.
    • Weber, W. A. and R. C. Wittmann. 2012. Colorado Flora, Eastern Slope, A Field Guide to the Vascular Plants, Fourth Edition. Boulder, Colorado. 555 pp.
    • Weber, W. A. and R. C. Wittmann. 2012. Colorado Flora, Western Slope, A Field Guide to the Vascular Plants, Fourth Edition. Boulder, Colorado. 532 pp.

Last Updated

2017-01-24