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Peabody Twentymile Coal Company 2004 Fish Creek AVF Riparian Vegetation Monitoring staked in the field with steel T-posts, numbered with aluminum tags and GPS surveyed. Due to extensive agricultural use at this site and the end goal of establishing the effects of subsidence, factors used to define community types were modified to better suite this study. Forest Service defined community types outlined in the GTR are based on vegetation communities common in natural riparian areas in which vegetation has not been significantly altered by anthropogenic activities (i.e. agriculture). The area to be surveyed at Twentymile Coal Company has been heavily influenced by agricultural activities and therefore, the native vegetation community types identified and used by the USFS are not applicable. Furthermore, the Forest Service methodology focuses on ascertaining the effectiveness of management practices in order to draw comparisons with potential natural communities that could exist in an ideal healthy riparian complex for a given area. Since monitoring at Twentymile Coal Company focuses-on composition and distribution, rather than estimated potentials, the vegetation community descriptions and methodologies have been modified to fit this site's conditions and evaluation purposes. To facilitate implementation and achieve consistent results on an annual basis, vegetation community sub-types were developed in 2003 based on dominant vegetation characteristics, while ignoring minor species components. These sub- types were then consolidated into community types based on shared inherent qualities (Table 1). For example, sparsely vegetated mud flats and eroded stream banks may have Carex species, Juncus species, or a combination of both. Since both species are strongly influenced by the effects of seasonal flooding and their proximity to ground water, both were included in the "Riparian" community type. Likewise, smooth brome (Bromus Inermis) and slender wheatgrass (Elymus trachycaulus) dominated grasslands both occur in similar ecological settings at this site, so they were grouped together in the "improved Pasture - Mesic° vegetation community type. Two additions were made to the 2003 classification system to more accurately describe transect composition in 2004. Specifically, the 2004 monitoring efforts incorporated a "Riparian -Open Water' classification, and the "Big Sage' community type was changed to "Sage Brush" to integrate a new "Black Sage' (Artemisia nova) community sub-type. Vegetation community composition was determined by traversing permanently established transects and recording the number of paces for each community sub-type encountered. The sub-types were grouped into community types and Habitat Management, Inc. Page 2 10/8/2004