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Ashley National Forest Assessment: Terrestrial Ecosystems, System

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Ashley National Forest Assessment: Terrestrial Ecosystems, System Ashley National Forest Assessment Terrestrial Ecosystems, System Drivers, and Stressors Report Prepared by: Allen Huber, ecologist Colette Webb, silviculturist Chris Plunkett, soil, water, air program manager Brad Gillespie, fuels management specialist (WO Enterprise) Chris Gamble, fuels specialist Joe Flores, fire management officer Dustin Bambrough, ecosystems staff officer for: Ashley National Forest September 2017 In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident. Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA’s TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English. To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at http://www.ascr.usda.gov/complaint_filing_cust.html and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: [email protected]. USDA is an equal opportunity provider, employer, and lender. We make every effort to create documents that are accessible to individuals of all abilities; however, limitations with our word processing programs may prevent some parts of this document from being readable by computer-assisted reading devices. If you need assistance with this document, please contact the Ashley National Forest at 435- 781-5118. Resource Report Name Ashley National Forest Assessment Contents Introduction ..................................................................................................................................... 1 Spatial Scale .................................................................................................................................... 1 Ecosystem Characteristics ............................................................................................................... 7 Rare and Unique Habitat Types .................................................................................................. 7 Calcareous or Rich Fens .......................................................................................................... 8 Peatlands or Fens (Glacial Canyons) ..................................................................................... 10 Peatlands or Fens (Limestone) .............................................................................................. 11 Composition and Distribution of Vegetation ............................................................................ 13 Alpine .................................................................................................................................... 13 Coniferous Forest .................................................................................................................. 21 Aspen ..................................................................................................................................... 31 Sagebrush .............................................................................................................................. 43 Pinyon and Juniper Woodlands ............................................................................................. 65 Desert Shrub .......................................................................................................................... 69 Structural Stages of Vegetation ................................................................................................. 78 Alpine .................................................................................................................................... 78 Aspen ..................................................................................................................................... 82 Coniferous Forest .................................................................................................................. 89 Pinyon Juniper Woodlands .................................................................................................. 111 Desert Shrub ........................................................................................................................ 113 Landscape Disturbances .......................................................................................................... 119 Geomorphic ......................................................................................................................... 119 Insects and Disease .............................................................................................................. 121 Fire....................................................................................................................................... 139 Literature Cited ............................................................................................................................ 154 Appendices .................................................................................................................................. 175 Appendix A. Description of Lodgepole Pine Structure .......................................................... 175 Appendix B. Description of Douglas-fir Structure ................................................................. 176 Appendix C. Description of Mixed Conifer Structure ............................................................ 176 Tables Table 1. National Hierarchical Framework of Ecological Units (domain, division, province, and section) on the Ashley National Forest.................................................................................... 2 Table 2. National Hierarchical Framework of Ecological Units, subsection level, on the Ashley National Forest ........................................................................................................................ 3 Table 3. Landtype associations on the Ashley National Forest ....................................................... 3 Table 4. Vegetation types on the Ashley National Forest ............................................................... 5 Table 5. Vegetation types evaluated in this assessment .................................................................. 5 Table 6. Vegetation types and acres in the alpine communities on the Ashley National Forest .. 13 Table 7. Alpine plant communities in the Alpine Moraine and Uinta Bollie landtype associations ............................................................................................................................................... 13 Table 8. Coniferous forest and associated seral aspen and coniferous. Woodland forest and persistent aspen are not displayed. ........................................................................................ 21 Table 9. Comparison of the mixed conifer and Engelmann spruce subalpine habitat types on the Ashley National Forest .......................................................................................................... 27 Table 10. Vegetation type and acres in aspen communities on the Ashley National Forest ........ 31 Table 11. Landtype associations that support aspen communities on the Ashley National Forest 31 i Resource Report Name Ashley National Forest Assessment Table 12. Vegetation type and acres in sagebrush communities on the Ashley National Forest . 44 Table 13. Landtype associations that support mountain big sagebrush (Artemisia tridentata var. vaseyana) on the Ashley National Forest .............................................................................. 44 Table 14. Landtype associations that support Wyoming big sagebrush (Artemisia tridentata var. wyomingensis) on the Ashley National Forest ...................................................................... 45 Table 15. Landtype associations that support black sagebrush (Artemisia nova) on the Ashley National Forest ...................................................................................................................... 46 Table 16. Vegetation type and acres for desert shrub communities on the Ashley National Forest ............................................................................................................................................... 69 Table 17. Landtype associations with known natural geomorphic disturbances ......................... 120 Table 18. Landtype associations
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