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Saussurea weberi

Hulten

Weber's Saw-wort

G3Vulnerable Found in 1 roadless area NatureServe Explorer →
G3VulnerableGlobal Rank
MediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.154379
Element CodePDAST8B060
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderAsterales
FamilyAsteraceae
GenusSaussurea
Concept Reference
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.
Taxonomic Comments
Previously treated as synonym of Saussurea densa, Saussurea weberi is now recognized as distinct by Kartesz' Synthesis (Kartesz 1999) and FNA (2006).
Conservation Status
Rank MethodLegacy Rank calculation - Excel v3.1x
Review Date2019-06-04
Change Date2019-06-04
Edition Date2019-06-04
Edition AuthorsOlivero, A. (2002), rev. A. Treher (2016), rev. J. Handwerk and A. Tomaino (2019), rev. Treher (2020)
Threat ImpactMedium
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences6 - 80
Rank Reasons
Saussurea weberi extinction risk is likely due in part to discontinuous habitat availability across a limited geographic range and restricted habitat requirements. It occurs in Colorado, Wyoming, and Montana, where it is confined to small areas of suitable alpine habitat. Motorized and non-motorized recreation, including hikers, 4-wheel drive and OHV users, and past and future mining are the predominant threats to this species.
Range Extent Comments
Saussurea weberi is a regional endemic of southwest Montana, northwest Wyoming, and central Colorado (USDA NRCS 2017). It occurs in the Gros Ventre and northern Wind River Ranges (Fremont, Sublette and Teton Counties) of Wyoming; Custer, Lake, Park, and Summit Counties in Colorado; and the Anoconda-Pintler Range of Montana.
Occurrences Comments
There are 14 principal occurrences documented in the Colorado Natural Heritage Program database as of 2019. There are 2 occurrences documented in Montana (NatureServe Network Database as of June 2019). In Wyoming, known from 1 (Fertig 2000).
Threat Impact Comments
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-moderate, 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).
Ecology & Habitat

Description

Saussurea weberi is a dwarf perennial herb that is 5-20 cm high and 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.

Diagnostic Characteristics

The clustered, purple, rayless flowering heads, together with the high elevation habitat, are distinctive. The similar S. DENSA, occurring in the northwest mountains, has narrow, pointed involucral bracts.

Habitat

This species generally occurs on rocky, exposed limestone slopes, talus, and ridges, in high elevation, subalpine to alpine sites. Habitats include gravelly tundra slopes amid scree (often on solifluction lobes on exposed sites, with poorly developed, limestone- and dolomite-derived soils), alpine talus slopes on limestone-derived substrates, and moderately dry alpine meadows and adjacent slopes on northwest aspects, in well-developed, calcareous soils. Also occasionally found on sandstone or granite substrates. Communities include stable tundra associations on solifluction lobes (where co-occurring species include grasses, sedges, and small willows), alpine wetlands (where co-occurring species include Salix brachycarpa, Salix glauca, Betula glandulosa, and mosses), moderately dry to moist alpine meadows, alpine cushion plant communities, and, occasionally, Engelmann spruce woodland to stunted krummholz. However, many sites (e.g. disturbed fell fields) are sparsely vegetated.
Terrestrial Habitats
Forest/WoodlandWoodland - ConiferGrassland/herbaceousAlpineBare rock/talus/scree
Palustrine Habitats
HERBACEOUS WETLAND
Other Nations (1)
United StatesN3
ProvinceRankNative
WyomingS2Yes
MontanaS2Yes
ColoradoS2Yes
Threat Assessments
ThreatScopeSeverityTiming
3 - Energy production & miningLarge (31-70%)Moderate or 11-30% pop. declineLow (long-term)
3.2 - Mining & quarryingLarge (31-70%)Moderate or 11-30% pop. declineLow (long-term)
6 - Human intrusions & disturbanceLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)
6.1 - Recreational activitiesLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (1)
Montana (1)
AreaForestAcres
North Big HoleBeaverhead-Deerlodge National Forest52,227
References (19)
  1. 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.
  2. Ackerfield, J. 2015. Flora of Colorado. Botanical Research Institute of Texas, Fort Worth, TX. 818 pp.
  3. Colorado Native Plant Society. 1989. Rare plants of Colorado. Rocky Mountain Nature Association, Colorado Native Plant Society, Estes Park, Colorado. 73 pp.
  4. Dorn, R.D. 1984. Vascular plants of Montana. Mountain West Publishing, Cheyenne, Wyoming. 276 pp.
  5. Dorn, R. D. 2001. Vascular Plants of Wyoming. 3rd edition. Mountain West Publishing. Cheyenne, Wyoming. 412 pp.
  6. Fertig, W. 2000. <i>Saussurea weberi</i> 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.
  7. Fertig, W., C. Refsdal, and J. Whipple. 1994. Wyoming rare plant field guide. Wyoming Rare Plant Technical Committee, Cheyenne. No pagination.
  8. Flora of North America Editorial Committee (FNA). 2006a. Flora of North America north of Mexico. Vol. 19. Magnoliophyta: Asteridae, part 6: Asteraceae, part 1. Oxford University Press, New York. xxiv + 579 pp.
  9. Glisson, B. 2004. <i>Saussurea weberi</i> 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).
  10. 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.
  11. Lackschewitz, K. H. 1976. Montana mountain flora: new records. Madrono 23:360-362.
  12. Marriott, H. 1991. Field survey for <i>Androsace chamaejasme</i> var. <i>carinata</i> and <i>Saussurea weberi</i>, Northwest Wind River Range, Wyoming. Unpublished report to the Bridger-Teton National Forest. Wyoming Natural Diversity Database, The Nature Conservancy. 21 pp.
  13. Montana Natural Heritage Program. Montana Plant Field Guide. Online. Available: http://mtnhp.org/plants/plantguide.asp (Accessed 2006).
  14. 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.
  15. Strickler, D. 1990. Alpine Wildflowers. The Flower Press, Columbia Falls, Montana. 112 pp.
  16. The Colorado Native Plant Society. 1997. Rare Plants of Colorado, second edition. Falcon Press Publishing Co.,Inc. Helena, Montana. 105pp.
  17. USDA, Natural Resources Conservation Service, PLANTS Database [USDA PLANTS]. http://plants.usda.gov/. Accessed 2017.
  18. 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.
  19. Watson, T. J. and K. H. Lackschewitz. 1980. The genus <i>Saussurea</i>SAUSSUREA (Asteraceae-Cynareae) in Montana. Northwest Science 54(2):106-108.