Physaria congesta
Author: Rollins

Dudley Bluffs bladderpod

Brassicaceae (Mustard Family)

Close up of Physaria congesta by Jill Handwerk
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Close up of Physaria congesta by Janis Huggins
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Ranks and Status

Global rank: G1
State rank: S1
Federal protection status: USFWS Threatened
State protection status: None

[+] Description and Phenology

Physaria congesta by Annie Reiser. Please also see 1997 profile
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General description: Very small, densely tufted perennial, usually less than 2 cm across. Yellow flowers are in umbelliform racemes that barely exceed the basal leaves in height; the pedicels curved or sigmoid. Basal and cauline leaves are similar, spatulate, 1-5 mm wide, with no distinction between the blade and the petiole. Fruit are almost spherical. Plants have stellate hairs throughout. Very long, thin taproot (Spackman et al. 1997).

Look Alikes: The caudices of Lesquerella congesta are extremely short or non-existent; plants form a single tight and dense crown. The caudices of L. alpina are several; plants form a loose crown (Spackman et al. 1997.

Phenology: Floweris early April-May; fruiting late May-June.

[+] Habitat

Habitat of Physaria congesta by Peggy Lyon
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Habitat of Physaria congesta by Lisa Foy
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Barren, white shale outcrops of the Green River and Uinta Formations.  Outcrops are exposed along drainages through erosion from downcutting of streams (Spackman et al. 1997).  Dominant associated plant community is Pinyon-Juniper woodland.  Other associated taxa include: Purshia tridentata, Cercocarpus montanus, Gutierrezia sarothrae, and Achnatherum hymenoides.

Elevation Range: 6,119 - 6,555 feet (1,865 - 1,998 meters)

[+] Distribution

Distribution of Physaria congesta in Colorado.
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Colorado endemic: Yes
Global range: Known from Rio Blanco County, Colorado; it is found only along the Piceance and Yellow Creek drainages. Estimated range is 88 square kilometers (34 square miles), calculated in 2008 by the Colorado Natural Heritage Program in GIS by drawing a minimum convex polygon around the known occurrences.

[+] Threats and Management Issues

Summary results of an analysis of the status of Physaria congesta based on several ranking factors. This species was concluded to be "weakly conserved”. From Rondeau et al. 2011.
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Mining and oil and gas development are considered to be the primary threats to the species (Rondeau et al. 2011). Mining of oil shale and/or nahcolite solution could impact up to 100% of the occupied habitat. A new nahcolite plant at Yankee Gulch, across from Dudley Bluffs was built in 2000. The lease may extend into Ryan Gulch. Additionally, a new drill pad was observed near Dudley Bluffs in 2000 (CNAP 2000). Other threats include livestock grazing and trampling by wild horses. ORV's can cause severe damage if access is allowed into the habitat.

[+] References

    • Ackerfield, J. 2012. The Flora of Colorado. Colorado State University Herbarium. 433 pp.
    • Al-Shehbaz, I. A., and S. L. O'Kane. 2002. Lesquerella is united with Physaria (Brassicaceae). Novon 12:319-329.
    • Colorado Native Plant Society. 1989. Rare plants of Colorado. Rocky Mountain Nature Association, Colorado Native Plant Society, Estes Park, Colorado. 73 pp.
    • Elliott, B. A., S. Spackman Panjabi, B. Kurzel, B. Neely, R. Rondeau, M. Ewing. 2009. Recommended Best Management Practices for Plants of Concern. Practices developed to reduce the impacts of oil and gas development activities to plants of concern. Unpublished report prepared by the Rare Plant Conservation Initiative for the National Fish and Wildlife Foundation.
    • Goodrich, S., and E. Neese. 1986. Uinta Basin flora. U.S. Forest Service, Intermountain Region, Ogden, Utah. 320 pp.
    • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
    • 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.
    • Roberts, R. 1990. White River RMP/EIS Management Situation Analysis, Resource Area Profile.
    • Rocky Mountain Society of Botanical Artists. 2009. RARE Imperiled Plants of Colorado, a traveling art exhibition. Exhibition catalogue developed by the Denver Botanic Gardens and Steamboat Art Museum.
    • 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.
    • U.S. Fish and Wildlife Service. 1990. Endangered and threatened wildlife and plants: final rule to determine Lesquerella congesta and Physaria obcordata to be threatened species.
    • U.S. Fish and Wildlife Service. 1993. Dudley Bluffs bladderpod and Dudley Bluffs twinpod recovery plan. Denver, Colorado.
    • USDA, NRCS. 2013. The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.
    • 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.

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