ATTACHMENT SS2

REGION 2 SENSITIVE SPECIES EVALUATION FORM

Species: Cymopterus williamsii / Williams’ Spring-parsley, Williams’ Wafer-parsnip

Criteria Rank Rationale Literature Citations Williams’ spring-parsley is a state endemic restricted to the Bighorn Mountains of • Beauvais et al. 2000 1 DA north-central in Bighorn, Johnson, Natrona, and Washakie Counties. There Distribution • Dorn 2001 within R2 is one historic record collected in 1900 that may lie within the Bighorn National Forest, • Fertig 1993 but this species is not otherwise known from Bighorn National Forest and national • Fertig 1999 forest lands in Region 2. • Fertig 2000a • Fertig 2000b Cymopterus williamsii occurs primarily on open, south or east-facing ridgetops and • Girard 1992 upper slopes with exposed limestone outcrops or talus at 6000-8300 feet. Soils tend to • Hartman and Constance 1985 be thin, sandy, and often restricted to small cracks or pockets in limestone bedrock. • Hartman and Nelson 1995 Barren rock can provide up to 50% of total cover. This species is usually absent or very uncommon where grass cover is high or where Cercocarpus ledifolius and Pinus • Neighbours and Marriott 1991 ponderosa are dominant. It also tends to be absent from lower slopes or valley • University of Wyoming 1998 bottoms with deeper or better-developed soils. Common associates include Astragalus • Welp et al. 1998 miser var. decumbens, A. spatulatus, Lesquerella alpina, Paronychia depressa, and • Welp et al. 1998 Hymenoxys acaulis. Such habitats represent a variety of substrates and vegetation • Welp et al. 2000 types that are extensive though discontinuous on the Bighorn Mountains landscape, resulting in a patchy distribution.

Confidence in Rank High It does not occur outside Region 2 (see above). • - 2 A Distribution outside R2 Confidence in Rank High Not known. • - 3 D Dispersal Capability

Confidence in Rank High

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Species: Cymopterus williamsii / Williams’ Spring-parsley, Williams’ Wafer-parsnip

Criteria Rank Rationale Literature Citations Cymopterus williamsii is known from 23 extant occurrences (last observed in 1999) • Fertig 2000a 4 DA and 1 historical record. Only the latter is on or near national forest lands so its Abundance in • WYNDD 2001 R2 abundance on Region 2 is unknown. Several of the recently-documented occurrences are in close proximity and might be better recognized as metapopulations, rather than individual occurrences. Populations are often quite large and the species may be one of the dominant in specific microsites. Approximately 72,000 plants were located during 1992 surveys on BLM lands in the southern Bighorn Range (Fertig 1993). It is ranked “S3” in Wyoming based on the number of occurrences and low threat.

Confidence in Rank Medium Populations are probably stable. Long-term monitoring is recommended to determine • Fertig 2000a 5 B trends. Population Trend in R2

Confidence in Rank Low The rugged ridgetops on which this occurs have most likely not diminished in habitat • - 6 B quality for this species. Such landscapes do not offer significant potential for human Habitat Trend in R2 use.

Confidence in Rank Medium Threats are low. Cattle and sheep do not graze this . Localized habitat loss, such • Fertig 2000a 7 C as a limestone quarrying, would have an impact. This species occurs on lands Habitat Vulnerability managed for multiple use by the BLM Buffalo, Casper and Worland Field Offices. One or or two populations are found within the BLM's North Fork Wilderness Study Area. Modification Confidence in Rank Medium Williams' spring parsley is a tufted, perennial herb. The inflorescence is a ball-like, • Fertig 2000a 8 D compound umbel of small yellow flowers. Flowering occurs from May through mid- Life History and June. Fruiting occurs from June to July. Demographics Other life history information on this species, including life history stages, population structure, longevity, mortality, pollination biology and seed biology, are not available.

Confidence in Rank High Initial Evaluator(s): Date: February 18, 2002 Bonnie Heidel and Scott Laursen

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National Forests in the Rocky Mountain Region where species is KNOWN (K) or LIKELY(L)1 to occur:

Colorado NF/NG NF/NG NF/NG South Dakota Wyoming NF/NG

NF/NG

y y

y y y Known Known Likel Likel Known Likel Known Likel Known Likel Arapaho-Roosevelt NF Cimmaron NG Samuel R.McKelvie NF Black Hills NF Shoshone NF White River NF Halsey NF Buffalo Gap NG Bighorn NF ? Routt NF Nebraska NF Ft. Pierre NG Black Hills NF Grand Mesa, Ogalala NG Medicine Bow NF Uncompahgre, Gunnison NF San Juan NF Thunder Basin NG Rio Grande NF Pike-San Isabel NF Comanche NG

Literature cited Beauvais, G.P., W. Fertig, and G.P. Jones. 2000. Rare species and the vegetation of Washakie County, Wyoming. Report prepared for the Washakie County planner by the Wyoming Natural Diversity Database, Laramie, WY.

Dorn, R.D. 2001. Vascular Plants of Wyoming, third edition. Mountain West Publishing, Cheyenne, WY.

Fertig, W. 1993. Field Survey for Cleome multicaulis, Cymopterus williamsii, and Sullivantia hapemanii in north-central Wyoming. Report prepared for the Casper District, BLM, by the Wyoming Natural Diversity Database, Laramie, WY.

Fertig, W. 1999. The status of rare plants in the Bighorn Landscape. Report prepared for The Nature Conservancy Wyoming Field Office by the Wyoming Natural Diversity Database, Laramie, Wyoming.

Fertig, W. 2000a. State Species Abstract: Cymopterus williamsii. Wyoming Natural Diversity Database. Available on the internet at www.uwyo.edu/wyndd

1 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.

USDA-Forest Service R2 Sensitive Species Evaluation Form Page 3 of 4 ATTACHMENT SS2 Fertig, W. 2000b. Rare vascular plant species in the Wyoming portion of the -Wyoming Rocky Mountains Ecoregion. Prepared for the Wyoming Nature Conservancy by the Wyoming Natural Diversity Database, Laramie, WY.

Fertig, W., C. Refsdal, and J. Whipple. 1994. Wyoming Rare Plant Field Guide. Wyoming Rare Plant Technical Committee, Cheyenne Wyoming.

Girard, M. 1992. Sensitive and Watch Plant Species of the Bighorn National Forest. Bighorn National Forest, 1969 S. Sheridan Ave., Sheridan, WY.

Hartman, R. L. and B. E. Nelson. 1995. Final report on the general floristic inventory of the southern Powder River Basin and Eastern Plains, Wyoming. Unpublished report prepared for the BLM Wyoming State Office by the Rocky Mountain Herbarium.

Hartman, R. L. and L. Constance. 1985. Two new species of Cymopterus (Umbelliferae) from western . Brittonia 37 (1): 88-95.

Neighbours, M. and H. Marriott. 1991. Candidate sensitive plant species, Platte River Resource Area, Bureau of Land Management. Prepared for the BLM by the Wyoming Natural Diversity Database, Laramie, WY.

University of Wyoming – Rocky Mountain Herbarium. 1998. Atlas of the Flora of Wyoming. Posted electronically thru 1998 at: http://www.esb.utexas.edu/tchumley/wyomap/ and unposted accession information at the Rocky Mountain Herbarium through 2001.

Welp, L., W. Fertig, and G. Jones. 1998. Ecological Evaluation of the Potential Crazy Woman Creek Research Natural Area Within the Bighorn National Forest, Johnson County, Wyoming.

Welp, L., W. Fertig, and G. Jones. 1998. Ecological Evaluation of the potential Pheasant Creek Research Natural Area Within the Bighorn National Forest, Johnson County, Wyoming. Unpublished report prepared by the Wyoming Natural Diversity Database, Laramie, WY.

Welp, L., W.F. Fertig, G.P. Jones, G.P. Beauvais, and S.M. Ogle. 2000. Fine filter analysis of the Bighorn, Medicine Bow, and Shoshone National Forests in Wyoming. Wyoming Natural Diversity Database, Laramie, WY.

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