ATTACHMENT SS2

REGION 2 SENSITIVE SPECIES EVALUATION FORM

Species: Equisetum sylvaticum / Woodland Horsetail

Criteria Rank Rationale Literature Citations Region 2 represents the southcentral portion of Woodland horsetail’s distribution. • Dorn 1982 1 A In Wyoming, it is known only from the Black Hills National Forest (Crook County) and Distribution • Dorn 2001 within R2 the Bighorn Mountains (Sheridan County) in Bighorn National Forest. It also occurs in • Evert and Hartman 1984 South Dakota. • Fertig 1999 • Fertig 2000a Woodland horsetail is found in wet meadows, marshes, streambanks, and moist • Fertig 2000b woods, often on subacidic soils (Lellinger 1985) from 4000-5900 feet in elevation. • Fertig 2000c

• Larson and Johnson 1999

• Nature Serve 2002

• Neighbours and Culver 1990 • University of Wyoming 1998 Confidence in Rank High • Welp et al. 2000 Outside of Region 2, Woodland horsetail occurs from Alaska to Newfoundland south to • Fertig 2000a 2 C Washington, Wyoming, South Dakota, Iowa, and West Virginia. Distribution • Great Plains Flora outside R2 Association 1986 • Hitchcock et al. 1969 Confidence in Rank High • Lellinger 1985 • Nature Serve 2002 3 C Woodland horsetail has a limited spore dispersal period, and spores are short-lived. • Fertig 2000a Sexual reproduction is limited by the gametophyte’s narrow habitat tolerance. Dispersal • USDA Forest Service 2002 Capability Woodland horsetail also colonizes recently burned areas by wind-dispersed spores. Wood horsetail primarily reproduces by vegetative means; the majority of shoots arise from rhizomes. Woodland horsetail survives repeated fires by means of deeply buried rhizomes that are apparently almost indestructible. The extensive rhizome system penetrates well into mineral soil or clay, allowing revegetation even after severe fire. Its phenotypic plasticity enables it to survive the environmental changes associated with postfire succession. Such adaptations offer resistance to disturbances as well as the ability to disperse over unsuitable habitats.

Confidence in Rank Medium

USDA-Forest Service R2 Sensitive Species Evaluation Form Page 1 of 5 ATTACHMENT SS2

Species: Equisetum sylvaticum / Woodland Horsetail

Criteria Rank Rationale Literature Citations Woodland horsetail is known from 3 occurrences in Wyoming, all of which have been • Fertig 2000a 4 A located since 1983 (most recently in 1999). One population at Preacher Rock Bog Abundance in • NatureServe 2002 R2 numbered in the thousands in July 1999 as indicated by stem counts (ramets). The • University of Wyoming 2002 total area of occupied habitat, however, is quite limited (less than 15 acres) and the total number of genets may be significantly lower than ramets. Population counts are not available from the Black Hills.

It is currently ranked “S1” in Wyoming. It is present but not ranked in South Dakota.

Confidence in Rank High Not known. • - 5 D Population Trend in R2

Confidence in Rank High Not known. • - 6 D Habitat Trend in R2

Confidence in Rank High Woodland horsetail may be vulnerable to habitat loss from wetland draining, logging, • Fertig 2000a 7 BD or high recreation use. It occurs on Black Hills and Bighorn national forests, which are Habitat • University of Wyoming 1998 Vulnerability managed for multiple use. or Modification Confidence in Rank Low

USDA-Forest Service R2 Sensitive Species Evaluation Form Page 2 of 5 ATTACHMENT SS2

Species: Equisetum sylvaticum / Woodland Horsetail

Criteria Rank Rationale Literature Citations Woodland horsetail is a perennial, deciduous, homosporous pteridophyte. Fertile • Fertig 2000a 8 D stems are at first unbranched and lack chlorophyll but become branched and green Life History • Hitchcock et al. 1969 and after spores are released. Strobili are usually 1 inch (3 cm) long and are borne on • University of Wyoming 1998 Demographics short stalks at the apices of fertile stems. The spores germinate to produce a distinct • USDA Forest Service 2002 gametophytic generation. Spores are produced in strobili in May and early June. Woodland horsetail has extensive creeping rhizomes, which may outweigh aerial shoots by a ratio of 100 to 1.

Life history information on this species, including life history stages, population structure, longevity, mortality, pollination biology and spore/gamete biology, are not available.

Confidence in Rank High Initial Evaluator(s): Date: February 6, 2002 Scott Laursen and Bonnie Heidel National Forests in the Rocky Mountain Region where species is KNOWN (K) or LIKELY(L)1 to occur: Colorado NF/NG Kansas NF/NG Nebraska NF/NG South Dakota Wyoming NF/NG

NF/NG

y y

y y y Known Likel Known 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 X Routt NF Nebraska NF Ft. Pierre NG Black Hills NF X 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

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 5 ATTACHMENT SS2 Dorn, R.D. 1983. Lycopodium complanatum and L. annotinum found in the Black Hills. American Fern Journal 73: 62.

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

Evert, E. F. and R. L. Hartman. 1984. Additions to the Vascular Flora of Wyoming. Great Basin Naturalist 44: 482-483.

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: Equisetum sylvaticum. Wyoming Natural Diversity Database. Available on the internet at www.uwyo.edu/wyndd

Fertig, W. 2000b. Target plant species and potential plant conservation sites in the Wyoming portion of the Black Hills Ecoregion. Report prepared for The Nature Conservancy Midwest Science Division by the Wyoming Natural Diversity Database, Laramie, WY.

Fertig, W. 2000c. Rare vascular plant species in the Wyoming portion of the Utah-Wyoming Rocky Mountains Ecoregion. Prepared for the Wyoming Nature Conservancy by the Wyoming Natural Diversity Database, Laramie, WY.

Great Plains Flora Association. 1986. Flora of the Great Plains. Univ. Kansas Press, Lawrence, KS.

Hitchcock, C.L., A. Cronquist, and M. Owenbey. 1969. Pt. 1. Vascular Cryptograms, Gymnosperms, and Monocotyledons, IN: Hitchcock, C.L., A. Cronquist, M. Owenbey, and J.W. Thompson (eds). Vascular Plants of the Pacific Northwest. University of Washington Publications in Biology 17(1): 1- 914.

Larson, G.E. and J.R. Johnson. 1999. Plants of the Black Hills and Bear Lodge Mountains. South Dakota State University College of Agriculture and Biological Sciences & South Dakota Agricultural Experiment Station, Brookings, SD.

Lellinger, D.B. 1985. A Field Manual of the Ferns and Fern Allies of the United States and Canada. Smithsonian Institution Press, Washington, D. C.

NatureServe. 2002. Explorer – an encyclopedia of life. Plant and animal data posted at www.natureserveexplorer.org, Arlington, VA.

Neighbours, M. and D. Culver. 1990. 1989 Floristic survey of Preacher Rock Bog, Bighorn National Forest, Wyoming. Report prepared for the Tongue Ranger District, Bighorn National Forest, by the Wyoming Natural Diversity Database, Laramie, WY.

U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (2002, February). Fire Effects Information System, [Online]. Available: http://www.fs.fed.us/database/feis/2002.

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

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.

USDA-Forest Service R2 Sensitive Species Evaluation Form Page 4 of 5 ATTACHMENT SS2

USDA-Forest Service R2 Sensitive Species Evaluation Form Page 5 of 5