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average indicator status of all plants in the sample and was performed as follows: Each Indicator Status was assigned a <br />corresponding multiplier ranging from 1 to 5, i.e., OBL species were assigned a multiplier of 1 and UPL species were <br />assigned a multiplier of 5. The Prevalence Index was calculated as (the sum of the total percent cover of each indicator <br />e status multiplied by its corresponding multiplier) / (the sum of the total percent cover for each indicator status). A <br />prevalence index less than 3 indicates that hydrophytic vegetation is present. The Prevalence Index test is used in cases <br />where wetland plant communities fail the dominance test and indicators of wetland hydrology and hydric soil are present. <br />Soils <br />In accordance with the Regional Manuals, soil test pits were excavated to depths needed to document hydric soil <br />indicators or to confirm the absence of indicators (30+ cm in most cases). A soil auger was used for sampling soil <br />materials below 30 cm if needed to confirm the presence of hydric soil indicators. Using a Munsell Soil Color Chart <br />(1975), the color of each soil horizon encountered was recorded on the Wetland Determination Data Form — Arid West <br />Region. Presence of mottles, oxidized root channels, or other evidence of anaerobic conditions (organic streaking in <br />sandy soils for example) was noted. Soil texture was also recorded for each horizon, as was depth to saturated soil (if <br />any). Additionally, Field Indicators of Hydric Soils in the United States (NRCS 1998) was used to provide supplemental <br />soils information. <br />*Hydrology <br />In areas of concave topographic position sufficiently low to become periodically inundated during flood events, direct and <br />secondary evidence of flooding (i.e. drift lines, watermarks, sediment deposits, etc.) were noted on the Wetland <br />Determination Data Form — Arid West Region wherever encountered. In the soil pits described above, depth to free <br />water was recorded where it was present, as was depth to saturated soil. <br />RESULTS <br />Vegetation <br />Wetlands in the study area can be classified as Palustrine, Riverine and Lacustrine. The water source for all of the <br />wetlands delineated is predominantly groundwater and snowmelt/runoff from the surrounding watershed, i.e., the "Grassy <br />Creek" watershed (12 -digit watershed hydrologic unit code 140500010511), which is within the Upper Yampa, Colorado <br />sub basin (hydrologic unit code 14050001) (USDA/NRCS, 1999). <br />*Natural Area NWI Classifications (Cowardin, 1979): <br />SYSTEM Lacustrine, SUBSYSTEM Limnetic, CLASS Open Water, WATER REGIME Permanently Flooded, <br />WATER CHEMISTRY Fresh. <br />