A Classification of Riparian Wetland Plant Associations of Colorado A Users Guide to the Classification Project September 1, 1999 By Gwen Kittel, Erika VanWie, Mary Damm, Reneé Rondeau Steve Kettler, Amy McMullen and John Sanderson 2 Clockwise from top: Conejos River, Conejos County, Populus angustifolia-Picea pungens/Alnus incana Riparian Woodland Flattop Wilderness, Garfield County, Carex aquatilis Riparian Herbaceous Vegetation South Platte River, Logan County, Populus deltoides/Carex lanuginosa Riparian Woodland California Park, Routt County, Salix boothii/Mesic Graminoids Riparian Shrubland Joe Wright Creek, Larimer County, Abies lasiocarpa-Picea engelmannii/Alnus incana Riparian Forest Dolores River, San Miguel County, Forestiera pubescens Riparian Shrubland Center Photo San Luis Valley, Saguache County, Juncus balticus Riparian Herbaceous Vegetation (Photography by Gwen Kittel) 3 Prepared by: Colorado Natural Heritage Program 254 General Services Bldg. Colorado State University Fort Collins, CO 80523 heritage@lamar.colostate.edu This report should be cited as follows: Kittel, Gwen, Erika VanWie, Mary Damm, Reneé Rondeau, Steve Kettler, Amy McMullen, and John Sanderson. 1999. A Classification of Riparian Wetland Plant Associations of Colorado: User Guide to the Classification Project. Colorado Natural Heritage Program, Colorado State University, Fort Collins, CO. 80523 For more information please contact: Colorado Natural Heritage Program, 254 General Service Building, Colorado State University, Fort Collins, Colorado 80523. (970) 491-1309 email: heritage@lamar.colostate.edu 4 ACKNOWLEDGEMENTS This project would not have been possible without the help, support and guidance of the Riparian Task Force. This cooperative group consists of The Nature Conservancy, the Colorado Natural Heritage Program, the Environmental Protection Agency, the US Forest Service, the US Bureau of Land Management, the US Bureau of Reclamation, US Park Service, US Natural Resources Conservation Service, The US Fish and Wildlife Service, the US Geological Survey, the Colorado Department of Health, the Colorado Division of Parks and Outdoor Recreation, the Colorado Department of Wildlife, and the Denver Board of Water Commissioners. I’d like to thank our funding sources, which, over the coarse of nine years, have contributed a total of $846,000. Grants ranged from large (>$50,000) to small (<$500), but every penny was needed, used and appreciated! Contributors are: EPA/State of Colorado, The Nature Conservancy, US Forest Service, Bureau of Land Management, Bureau of Reclamation, National Fish and Wildlife Foundation, Denver Water Board, City of Boulder, Colorado Natural Areas Program, Colorado Department of Health, Colorado Riparian Association, and the Colorado Native Plant Society. I need to thank and acknowledge Betsy Neely of The Nature Conservancy’s Colorado Field Office and Patrick Bourgeron, formerly of The Nature Conservancy’s Western Regional Office, for originating the project and designing the original sampling framework. Special thanks are in order to key folks who found funding, and contributed to the project by providing maps, field vehicles, training seminars, access information, hot showers, and an occasional backyard to camp in. These folks are: Brenda Mitchell, Jay Thompson, Leonard Coleman, Dave Wheeler, Dean Erhardt, Mike Cassell, Fred Bunch, John Kosak, Dave Gilbert, Barry Johnson, Amanda Clements, Tony Hoag, Dennis Murphy, Karen Hamilton, Sarah Fowler, Deb Mellbloom, Doug Robotham, and many, many others. I’d like to thank all the field crew members for putting up with long working hours, rain, bugs, extreme heat, occasional snow, cold, many days without showers, and many a long hike. These are all dedicated, hard working folks who went that extra mile every time. Some came to the project as veterans with years of experience; others were just starting their careers as field biologists. All gave their heart and soul to the cause. Some work on data entry and editing as well as field work. Some were with the project for multi-years, others only a few weeks. They were all were wonderful to work with and fun to be with in the field. I appreciate their hard-work, dedication, and neat handwriting! These wonderful folks are: Marion Reid, Sylvia Gindele, Brian Stanford, Nan Lederer, Margaret Condron, Sam Hammer, Todd Barker, Maureen DeCoursey, Susan Spackman, Reneé Rondeau, Dan Randolph, Julie Burt, Erika VanWie, Amy McMullen, Lea Spears, Mary Damm, Bill Grantham, Danielle Zoellner, Lisa Tasker, Sandy Scheck, Kathy Carsey, Camille Richard, Marty Aitken, Mindy Smith, Doug Grant, Steve Kettler, Mark Duff, Maggie March, John Sanderson, and Denise Culver. In addition, a hearty “thank you” goes to the many volunteers also assisted with fieldwork, data entry, mapping and transcribing records back in the office. I must also thank the many landowners, private, public and tribal, who granted us access to their lands, streams and creeks. It is thanks to their willingness and good land stewardship that made this project a success and allowed the classification to cover the full scope of Colorado riparian wetland resources. And lastly I must thank Dr. Dennis Knight, for turning me on to riparian ecosystems. 5 TABLE OF CONTENTS ACKNOWLEDGEMENTS........................................................................................................................... 4 SUMMARY ........................................................................................................................................................ 6 INTRODUCTION........................................................................................................................................... 7 METHODS........................................................................................................................................................ 8 Pre-Field Site Selection............................................................................................................... 8 Ariel Photograph Interpretation .................................................................................................. 9 Field Data Collection ................................................................................................................ 10 Site Ranking Criteria................................................................................................................. 12 Data Analysis and Classification Development........................................................................ 13 The United States National Vegetation Classification ...............................................................................13 A CLASSICATION OF RIPARIAN WETLAND PLANT ASSOCIATIONS..................................17 List of Riparian Wetland Plant Associations of Colorado........................................................ 17 List of CNHP Ranks ................................................................................................................. 22 Map of Plot Locations used to build the Riparian Classification (1990-1998), COError! Bookmark not defined. BASIN BY BASIN SUMMARY...................................................................................................................23 Arkansas River Basin ....................................................................................................................................24 Colorado River Basin....................................................................................................................................26 Gunnison River Basin...................................................................................................................................28 Lower San Juan River Basin.........................................................................................................................30 North Platte Watershed................................................................................................................................32 Rio Grande and Closed Basin Watersheds ................................................................................................34 Routt National Forest ...................................................................................................................................38 San Juan National Forest..............................................................................................................................40 San Miguel and Dolores River Basins ........................................................................................................43 South Platte Watershed ................................................................................................................................45 White River Basin..........................................................................................................................................48 Yampa River Basin........................................................................................................................................50 USER GUIDE to PLANT ASSOCIATION COMMUNITY CHARACTERIZATION ABSTRACTS (CCAs) .....................................................................................................................................51 LITERATURE CITED .................................................................................................................................54 APPENDIX 1. Key to Riparian Wetland Plant Associations of Colorado............................................69 APPENDIX 2. Riparian Field Form and Manual. .....................................................................................70 APPENDIX 3. Location, Rank, and Plant Association for each plot.....................................................71 6 SUMMARY This report presents the final Classification of Natural Riparian/Wetland Plant Associations for Colorado. This is the culmination of a nine year project to develop a comprehensive, field-based, classification of riparian wetland plant associations for the state of Colorado. Over 1880 quantitative plots were collected between 1990 and 1999, using a systematic, stratified-random method applied to all 12 watersheds in the state. One hundred fifty (150) native plant associations are described. These include conifer forests, deciduous woodlands, willow shrublands, non-willow shrublands, herbaceous meadows, alkaline flats, acidic fens, and alpine peat bogs that occur on USGS designated perennial and ephemeral streams at the 1:12,000 scale. Riparian wetlands include broad meandering river floodplains with complex mosaics of several plant associations, narrow stream reaches, to dry gullies. The classification also covers active alluvial rivers, beaver activity-driven ecosystems, and stable, subalpine wetlands. The classification does not described tamarisk and Russian olive dominated riparian areas, or areas dominated by other non-native plant species. However, with over 1880 plots, not all riparian areas sampled were in pristine condition. Sampling occurred on Federal, State, County, City and private land. Private land was only accessed with the permission of the landowner. Reference reaches were located in each watershed. Significant findings and Reference Reaches are summarized for each watershed. This classification covers an estimated 80-90% of Colorado’s riparian wetland diversity, so not all of the riparian associations that occur on the landscape are be described in this report. Some plant associations are very rare and unique to Colorado, known from five or fewer places in the state. Others are quite common, and are known from literately hundreds of streams. Of the one-hundred fifty riparian plant associations 11% (17) are ranked G1—critically imperiled globally; 17% (26) are ranked G2—imperiled globally, 29%(49) are ranked G3—vulnerable, 24% (36) are ranked G4—apparently secure globally, 15% (23) are ranked G5—demonstrably secure globally, and 1% (5) remained unranked. Colorado’s riparian areas cover less than 3 percent of the land area in the state, yet they house 40% of all the known plant species in the State, (1220 taxa), some of the rarest wetland plant associations known in the west, and provide habitat for nearly 80% of the wildlife species that live and migrate through Colorado This report includes: • A review of the project, office and field methods. • Review of findings and Reference Reaches in each River basin. • Table of 150 plant associations and their conservation ranks; CNHP rank definitions. • Vegetative Key to the Riparian Wetland Plant Associations of Colorado (Appendix 1). • Riparian field form used and its manual (Appendix 2). • A list of all plot locations, site rank and plant association (Appendix 3). 7 INTRODUCTION Riparian areas, highly used and abused in Colorado, are of great importance for maintaining water quality and quantity, stabilizing stream banks, and providing habitat for fish and other wildlife species (Hansen et al. 1988, Brinson et al. 1981). Riparian areas are the biological and physical link between terrestrial and aquatic ecosystems (Youngblood et al. 1985). These areas are used extensively for domestic livestock grazing, gravel mining, recreational purposes, and as transportation corridors. The ecology of riparian areas and their response to various land management practices is variable and often poorly understood. Consequently, resource management and conservation decisions for many riparian areas can be far from optimal. Our knowledge of riparian plant associations in Colorado has been both limited and fragmented. Patchy and scattered inventory work, using a variety of methodologies, has been conducted in Colorado. Areas include the Piceance Basin (Baker 1982), along the more accessible portions of the main stem of the Yampa River (by the Colorado Natural Areas Program), and the Yampa River within Dinosaur National Monument (Fisher et al. 1983). The Nature Conservancy has funded classification and surveys of riparian vegetation in west-central and southwestern Colorado (Baker 1986), and the northern Front Range (Cooper and Cottrell 1990). Plant community and habitat classification by the National Forests (Hess and Alexander 1986, Hess and Wasser 1982, Komarkova 1979, Komarkova et al. 1988, DeVelice et al. 1985) have not specifically focused on riparian areas. Elsewhere in the Rocky Mountain Region, riparian classification has been conducted in eastern Idaho and western Wyoming (Youngblood et al. 1985), eastern Wyoming (Jones 1990, Jones and Walford 1995), New Mexico (Muldavin 1992, Durkin et al. 1994, 1995), Montana (Hansen et al. 1988, 1989, 1995), Nevada (Manning and Padgett 1989, Manning and Padgett 1995), and Utah (Padgett et al. 1989). No single project or document describes what riparian wetland resources occur in Colorado, or how they may be related to this body of literature. The state wide classification project was designed to produce such a document. This project constitutes the first comprehensive riparian classification effort for Colorado. Since 1990, basin-wide, systematic riparian classification has been conducted each year, focusing on the 12 major watersheds of Colorado. At the same time, two National Forests and one National Grassland were sampled with the same methodology. Completed watersheds and Forest Service lands include: the Yampa and San Miguel/Dolores River basins (Kittel and Lederer 1993), the White and Colorado River basins (Kittel et al. 1994), the Gunnison River Basin (Kittel et al. 1995), the San Juan and Routt National Forests (Richard et al. 1996, Kettler and McMullen 1996), the South Platte watershed (Kittel et al. 1998), part of the Comanche National Grassland (Culver et al 1996), the Rio Grande and Closed Basins (Kittel et al. 1999), and the upper (I-25 corridor up to the continental divide) Arkansas River basin (Kittel et al. 1996). In 1998, we completed basin wide coverage of the entire state by continuing the method in the North Platte River basin, the lower San Juan River basin (below San Juan National Forest boundaries to the state line), and the lower Arkansas (roughly the I 25 corridor east to the state line, including the Cimarron River watershed). In this report, we present the final classification of riparian wetland vegetation for Colorado. Homogeneous stands of riparian vegetation are classified into Plant Associations based on similar floristic composition and environmental setting. The classification is part of the United States 8 National Vegetation Classification System (USNVS), developed and maintained by The Nature Conservancy (Grossman et al. 1998, Anderson et al. 1998). The classification is based on a hierarchical physiognomic and ecological structure (Grossman et al. 1998). In this report, we crosswalk Alliances and Plant Associations with Wetland and Deepwater Habitats of the United States (Cowardin et al. 1979). This classification is subject to peer review, field testing, and revision. As new data are collected from different basins, information will be incorporated into the classification. Information pertaining to rare or high quality occurrences of common plant associations will be incorporated into the Biological and Conservation Database of Rare and Imperiled Natural Communities, updated and maintained by the Colorado Natural Heritage Program (CNHP), and the Terrestrial Vegetation for the United States (Anderson et al. 1998). This project is a cooperative effort by the Riparian Task Force, a group of state and federal government agency representatives, which in cooperation with The Nature Conservancy's Colorado Program and the Colorado Natural Heritage Program, supports the project through in-kind services, financial support, and technical assistance. The Riparian Task Force, formalized in 1993 by a Memorandum of Understanding (MOU), consists of steering and technical committees that meet once a year to review methods and results, and to discuss the continued support for the statewide classification project. METHODS Riparian areas are defined as the interface between the riverine aquatic ecosystem and the adjacent upland ecosystem (Gregory et al. 1991, Risser 1990, Knopf et al. 1988, Brinson et al. 1981). These areas are frequently flooded, or are at least seasonally saturated by a fluctuating water table, and have plant species, soils, and topography that differ considerably from those of the adjacent uplands (Elmore and Beschta 1987, Jones 1990). Riparian areas studied during this project include vegetation occurring along natural water courses, poorly drained overflow areas, and associated natural bodies of water, such as oxbow lakes. The classification focuses on perennial and intermittent (streams that were marked perennial for at least 1 mile of their length) as defined on U.S. Geological Survey 1:24,000 and 1:100,000 topographic maps. Pre-Field Site Selection To sample as much of the diversity within each basin as possible in one field season, we used a stratified-random approach based on the Austin and Heyligers (1989) gradsect concept. Two environmental gradients thought to influence riparian vegetation were chosen to stratify the study area. Each mile of every stream within the study area was placed within a cell-type, a combination of the two stratifying variables. Two environmental variables used were: 1) stream order as a surrogate for basin size, channel size and stream volume (Schumm 1977, Knighton 1984), and 2) elevation as an important predictor of climate. Using USGS 1:100,000 topographic maps we denoted 1,000 ft (300 m) elevation bands from 5,000 ft (1,525 m) to over 10,000 ft (3,050 m) and first through fifth order stream classes, calculated for each mile of perennial stream using Strahler's (1952) system. 9 The total perennial and intermittent (streams that were marked perennial for at least 1 mile of their length) stream miles in the basin were tallied by cell type and their percentage for the basin calculated. Aerial photographs were used to eliminate areas of heavy disturbance (explained in more detail below). Over 200 one-mile long stream reaches were randomly selected in each study area, representing all the classification cell types, weighted by their abundance in the basin. For example, if 20% of the stream miles above 10,000 ft (3,050 m) were first order streams, then 20% of the randomly selected one-mile sites would be of that type. Thus the number of sampled stream miles per cell type was representative of the basin. In addition to sampling a representative selection of potential habitats, we also tried to sample riparian areas which have not been drastically altered by human activity in the sampling regime, thereby limiting the classification to plant associations native to Colorado, whose descriptions can serve as a reference point for management and restoration needs. This was not always possible, especially at lower elevations, and, of course, was subject to our own interpretation of natural and potential vs. changed vegetation due to human activities. We assumed that current wildlife populations and fire frequencies have been altered ubiquitously across the landscape and is constant “background noise” in our data set. The term “relatively undisturbed” refers to the difference between the most altered reach to the least altered reach within the watershed, as opposed to some theoretical “pristine” criteria. In any case, by observing riparian areas systematically across the watershed and the state, we have gained a pretty good idea as to the status, condition and trend of riparian ecosystems within the study area and across Colorado. Riparian corridors were ranked by their condition (amount of human-induced disturbance) at two scales. First, from small-scale color infrared aerial photographs (1989, 1990 NAPP 1:40,000, 1983 1:24,000) to block out obvious severely altered riparian reaches (see list of specific criteria starting on page 11). The amount of disturbance on surrounding lands can be a strong predictor of the amount of non-native species in the understory within the riparian corridor (Rondeau and Kittel 1994). Areas indicating heavy disturbance were eliminated prior to random selection of reaches for sampling. Second, each randomly chosen reach was evaluated again for its condition in the field (mainly for the amount of grazing impact and presence of non-native plant species, criteria that cannot be adequately assessed from small-scale photographs). Aerial Photograph Interpretation Disturbance criteria used for both small (aerial photography) and large (on the ground) scale assessments were: 1. Drastic disturbance where riparian vegetation has been removed or fragmented such that less than 50% of the riparian corridor remains in tact. Signs such disturbance at small scales are: agricultural/urban conversion, constricting or encroaching irrigated fields, square-edge fields, road and railroad embankments, channelized river reaches, power line maintenance roads, within channel and floodplain gravel mining, surrounding hillslope activities such as logging, and mining, and proximity to dams and reservoirs. 2. Heavy recreational use, such as off-road vehicle use, high density camping impacts, social trails and the like. 10 3. Chronic heavy livestock use (improper grazing practices) where hillside trailing occurs, accelerated bank erosion/destabilization, or abundant increaser species are present; basically sites with severe improper livestock management as outlined in Valentine (1990). 4. Road maintenance activities, including grading, bridge repair/improvements, road widening, snow-removal practices that impact vegetation; channel bed re-configuration for irrigation head gates, gravel/sand mining sites, or other dumping grounds. All riparian corridors were classified into four condition categories from the small scale (1:40,000) aerial photography assessment criteria: 1. Excellent-- riparian corridor and the surrounding area appear natural with no major disturbances. Within the corridor itself, the area appears unfragmented and the vegetation follows a natural pattern, and the corridor is large (>1 mile long); 2. Good--riparian corridor exhibits excellent vegetative cover but the surrounding area is somewhat altered, the corridor maybe large (>1 mile long) but somewhat disturbed, or the corridor smaller (<1 mile) but in excellent condition; 3. Fair-- the riparian corridor is fragmented, and/or the surrounding lands disturbed, the corridor may be very small (<1/4 mile long ), or larger (>1 mile) but disturbed for 50% or greater of its length; and 4. Poor-- riparian corridor disturbed, vegetation that is sparse or highly fragmented and the surrounding land slightly to drastically altered, the area may be very small (<1/4 mile) or very large (>1 mile) with severe disturbance for >80% of its length. Deep canyons are an exception to the above criteria, as they tend to have naturally low amounts of riparian vegetation. If the surrounding land looked undisturbed, a canyon reach would be ranked “good” also. BLM 1:100,000 topographic and land ownership maps were overlain with the aerial photographs. River miles were tallied by ownership (federal, state, and private) and condition category. During field site visits, we further evaluated randomly chosen reaches for the amount of improper grazing (difficult to asses from aerial photographs) and weedy species. Sites were eliminated from sampling if they were severely degraded by improper grazing as well as if they were dominated by non-native plant species such as tamarisk or salt cedar (Tamarix ramosissima) or Russian-olive (Elaeagnus angustifolia). Areas with non-natives present, such as Kentucky bluegrass (Poa pratensis), but where native flora dominated the overstory vegetation, were included in the sampling regime. Field Data Collection Field site visits were conducted June 1st through October 15th. Private land was accessed only with landowner permission. Each randomly chosen reach was assessed in the field for quality condition. Once a site has passed the “relatively undisturbed test” (explained in the previous section), we proceed to collected the following data at each plot: • elevation (from 7.5 min. topographic maps) • aspect and stream bearing • valley floor width (from topographic maps) • stream gradient (measured with a hand level and stadia rod) • channel depth and width (measured at bankfull or average annual high water mark) Bankfull stage or Bankfull channel is the height of the average 1-3 year return flow, also called the average annual high water mark of the active channel (Knighton 1984, Wolman and Leopold 1957). We use 11 this demarcation along the bank as a reference point for measuring stream channel width and depth, and the height and distance of a riparian community from the active channel. • Stream reaches were placed into Rosgen's Stream channel classification (Rosgen 1994). This system is based on the channel width to depth ratio, available floodplain width, channel gradient and sinuosity, among other criteria. • Hydrologic and geomorphic features (beaver dams, point bars, etc.) • History of use (from landowner or manager) when obtainable • Woody vegetation was quantitatively sampled for percent cover using 30-50 m long line- intercept transects, oriented parallel to the stream channel. Transects were subjectively located within a homogeneous portion of each stand to best represent the vegetation of the site. • Herbaceous vegetation was sampled using 10-20 0.10 m2 micro-plots, located about every third meter along a transect and 1 meter to the side, alternating sides. • Woody and Herbaceous vegetation was measured as percent canopy cover by vascular plant species to the nearest 10% in the following cover classes: 5-15%, 16-25%, 26-35%, 36-45%, 46- 55%, 56-65%, 66-75%, 76-85%, 86-95%, and >95%. Plant cover 5% or less was estimated into two categories, <1% and 1-5%. • Total canopy cover by life form (trees, shrubs, graminoids, and forbs). Overhead tree cover was measured along the transect using a clinometer to find the vertical intercept of the tree canopy. • Ground cover of bare soil, litter, wood, gravel, rock, bryophyte, and non-vascular plants • Soils were described from a single pit within each stand sampled. Pit depth varied according to the amount of coarse fragments present (average depth 70 cm). Noted from each horizon: thickness, texture, color, % mottling/gleying, matrix color, % coarse fragments, % organic matter, overall thickness, and parent material, when possible. • Height above the active channel using a hand held level and stadia rod. • Distance from transect to active channel (using a measuring tape or hip-chain). • Landscape position (point bar, floodplain, abandoned channel, terrace, etc.). • Signs of wildlife or domestic livestock utilization. • Signs of disturbance (flooding, fire, wind throw, logging, etc.). • Successional relationships where trends could be inferred. • Adjacent riparian and upland vegetation. • Reference site and plot 35 mm color slides. • Size of occurrence mapped on 7.5 min. USGS topographic maps with aid of 9 x 9 in. 1:40,000 NAPP color infra red aerial photos. Plant species scientific nomenclature follows Kartez (1994), except for the genera Salix (willows), which follows Dorn 1995. All plants not identified in the field, particularly of difficult genera such as Salix, Carex, and Juncus, were collected, pressed, and identified (to species level when possible) at the University of Colorado and Colorado State University Herbaria. Voucher specimens will be deposited at the University of Colorado Herbarium, the University of Wyoming Rocky Mountain Herbarium, and the Colorado State University Herbarium. 12 Site Ranking Criteria A Site Quality Rank was given to each riparian area sampled. These range from A (highest) through D (poorest) for overall riparian health and condition. In 1995 overall riparian quality was an average of the following four criteria: Quality--overall size, connectedness to surrounding natural ecosystems, degree of alteration; Condition--abundance of non-native plant species, degree of soil compaction, amount of species composition change by livestock grazing, degree of human disturbance, appropriateness of current management for riparian ecosystem health; Viability—are extrinsic factors necessary for long term survival of this ecosystem (e.g. hydrological processes, overall trend of site under current management) present?; Defensibility--extrinsic and intrinsic factors affecting the long term existence of the ecosystem; any known threats or site specific problems are defined; adjacent land use compatibility is included. In 1997, riparian quality ranking criteria was revised, using the same scale (A through D) and again an average of the following criteria: Size—the extent of the community, now and relative to its presettlement extent. Condition—An integrated measure of the quality of biotic and abiotic factors (structure and processes) at the local, within site (riparian mosaic) scale, including the occurrence and the degree to which they affect the continued existence of the stand. This includes: stand age, ecological processes, species composition, and abiotic physical factors (e.g. stability of substrate, water quality and soil compaction); and Landscape Context—An integrated measure of the quality of biotic and abiotic factors at the landscape scale, structures and processes surrounding the site area including the riparian area itself. Note the adjacent land use(s), the degree of habitat fragmentation in the surrounding landscape. What hydrologic manipulation has occurred within the watershed? See Appendix 3 for examples of the 1995 and 1997 plot forms (page 3 of the forms has site ranking criteria). For example, an A- ranked occurrence of a riparian plant association has no, or very few, non- native plant species present, the channel and banks are stable and show no signs of trampling or sloughing, and the soils are not compacted. The association is surrounded by other riparian associations of similar quality, creating a connected, high quality mosaic. The surrounding hillslopes and areas up and down stream are in natural condition and have not been drastically altered (no dams or diversions upstream, no logging or mining up stream of adjacent hillslopes). A B-ranked occurrence of a riparian plant association may have all of the above `A' criteria but is very small in size, or has a higher abundance of non-native plant species present, or may be an area in high condition with surrounding land use that fragments the occurrence. A C-ranked occurrence is of poor condition, generally with abundant non-native plant species present and/or the area is highly fragmented, and/or the area is very small. Again surrounding land use and condition plays a role in the overall riparian occurrence rank. Riparian areas recommended for special management or protection are examples of "A" or "B" ranked occurrences. These ecologically significant sites are valuable as reference areas for long-term research and comparison with impacted areas. High-quality riparian areas found in the Rio Grande and Closed Basin are proposed as some of the best examples of rare or common riparian plant associations in the State. The Colorado Natural Heritage Program will be entering these areas into the Biological and Conservation Database and ranking these sites for final protection recommendation. 13 Data Analysis and Classification Development Agglomerative cluster analysis was employed using Euclidean distance (a similarity index distance measure) and average clustering method to determine groups of plots with similar species abundance (Figures 4, 5 and 6)(see Ludwig and Reynolds 1988 for further explanation of this method). Plant Associations derived from the cluster analyses were compared with riparian plant association stand data and descriptions from riparian classification work in Colorado, New Mexico, Arizona, Utah, Montana, Idaho and Wyoming (Johnston 1987, Muldavin 1992, Durkin et al. 1994, 1995, Szaro 1989, Padgett et al. 1989, Hansen et al. 1988, 1989, and Youngblood et al. 1985, respectively). Associations were considered either 1) synonymous --where associations matched in species composition, constancy, average cover, environmental setting, 2) similar --when canopy structure, genera, and physical setting were similar, but species composition was different, 3) a new type not described in the literature, or 4) unclassifiable due to insufficient data. Plant association names are based on each canopy stratum dominant and codominant plant species, characterized by high constancy (frequency of species occurrence) and high relative abundance (percent canopy cover) values. A slash separates canopy layers (e.g., tree/shrub/herb). A dash indicates co-dominance within a given canopy layer (e.g., Populus angustifolia-Pseudotsuga menziesii). Plant associations that appear synonymous with those in the literature (by stand table and description comparison) are given the same names. Some published names are long and awkward; we propose shorter names herein. The United States National Vegetation Classification (USNVS) Riparian plant associations presented here are incorporated into the United States National Vegetation Classification System (USNVS), developed and maintained by The Nature Conservancy (Grossman et al. 1998, Anderson et al. 1998). This system is based on key elements to best incorporate existing systems and information, and to best fit the needs of conservation. The classification: 1) is vegetation-based, 2) uses a systematic approach, 3) emphasizes natural vegetation, 4) emphasizes existing vegetation, 5) uses a combined physiognomic-floristic hierarchy, identifying vegetation units at scales practical for conservation, and 6) is appropriate for mapping at multiple scales (emphasis by the author). The classification is based on existing, relatively undisturbed (by human impacts) vegetation in all seral stages. A plant association, the most specific level in this hierarchical classification, is defined as “natural vegetation with definite floristic composition, uniform physiognomy, and uniform habitat” (Mueller-Dombois and Ellenberg 1974). This is not the same as the USDA Forest Service adopted concept of a “plant association” (Daubenmire 1952), a term reserved for only the potential climax vegetation. Plant associations in the USNVS system are defined as a product of the prevailing environmental setting (where possible, barring human influence or pre-European settlement) including past natural disturbances (such as fire, flooding, or bison grazing) and are "real, extant ... kinds of vegetation, rather than a theoretical end point that is seldom reached on most sites" (Baker 1984). Along riparian corridors, flooding and sediment deposition and scouring create an environment that is frequently disturbed. Thus most riparian communities are frequently set back in successional time, and the floodplain mosaic is often a series successional stages. Thus many of the plant 14 associations described here would be equal to “community types” described by USDA Forest Service publications (e.g. Padgett et al. 1989). The Hierarchical Physiognomic and Floristic Classification of the United States National Vegetation Classification System (USNVS) is structured as follows: • Division-- the first level in the classification system separates the Earth into either vegetated (>1%) or non-vegetated categories. • Order-- Dominant life form (tree, shrub, dwarf shrub, herbaceous, or non-vascular). • Class-- Relative percent canopy cover of the life form in the upper most strata during the peak of the growing season (Forest, woodland, shrubland, and barrens). • Subclass--Predominant leaf phenology of the classes defined by tree, shrub, or dwarf shrub stratum (evergreen, deciduous, mixed evergreen-deciduous), and the average vegetation height for herbaceous stratum (tall, medium, short). • Group-- A combination of climate, leaf morphology, and leaf phenology (e.g. Subtropical drought-deciduous forest, Temperate rainforest). • Subgroup-- Separates natural/semi-natural types from the planted/cultivated types. • Formation--Ecological groups with broadly defined environmental (e.g. hydrology) and additional physiognomic factors (e.g.). • Alliance--aggregation of Plant Associations and characterized by a diagnostic species, which as a rule, occur in the dominant or uppermost stratum of the vegetation (Picea pungens Seasonally Saturated Alliance). • Plant Association-- the basic floristic unit of this classification system, characterized by a diagnostic species that occur in the overstory and understory of the vegetation (e.g. Picea pungens/Alnus incana Seasonally Saturated Forest). 15 Cross-reference of the US National Vegetation Classification (USNVC) (Grossman et al. 1998 and Anderson et al. 1998) and the Wetland and Deep Water Habitat Types of the U.S. (Cowardin et al. 1979). ____________ USNVC COWARDIN DIVISION: Vegetated (>1%) Order: Tree Dominated Class: II. Open Tree Canopy (25-60%) Subclass: A. Evergreen Open Tree Canopy Group: 4. Temperate or subpolar Subgroup: (N). Natural/Semi-natural Formation: e. Seasonally flooded/ saturated Floristic level (1) Alliance Floristic level (2) Plant Association Subclass: B. Deciduous Open Tree Canopy Group: 2. Cold-deciduous Subgroup: (N). Natural/Semi-natural Formation: c. Seasonally flooded/ saturated Floristic level (1) Alliance Floristic level (2) Plant Association Subclass: C. Mixed evergreen-deciduous Group: 3. Cold-deciduous Subgroup: (N). Natural/Semi-natural Formation: b. Seasonally flooded/saturated Floristic Level (1) Alliance Floristic Level (2) Plant Association Order: Shrub Dominated Class: Shrubland Subclass: B. Deciduous Shrubs Group: 2. Cold-deciduous Subgroup: (N). Natural/Semi-natural Formation: b. Subalpine or subpolar Floristic level (1) Alliance Floristic level (2) Plant Association Formation: c. Seasonally flooded/saturated Floristic level (1) Alliance Floristic level (2) Plant Association Order: Herb/Nonvascular Class: Herbaceous Dominated Subclass: A. Perennial graminoid (>50% relative graminoid cover) Group: Temperate or subpolar grassland Subgroup: (N). Natural/Semi-natural Formation: k. Seasonally flooded/ saturated Palustrine system-Forested class Needle-leaved evergreen subclass (Dominance type) Palustrine system-Forested class Broad-leaved deciduous subclass (Dominance type) Palustrine system-Forested class Broad-leaved deciduous subclass (Dominance type) Palustrine-Scrub-Shrub Shrubland Deciduous--class (Dominance type) (Dominance type) Palustrine-Emergent Persistent Wetlands Cross reference of USNVC and Cowardin, Continued. USNVC COWARDIN 16 Floristic level (1) Alliance Floristic level (2) Plant Association Subclass: Perennial Forb vegetation (50% relative >forb cover) Group: 2. Temperate or subpolar Subgroup: (N). Natural/Semi-natural Formation: e. Saturated temperate forb vegetation Floristic level (1) Alliance Floristic level (2) Plant Association Subclass: Hydromorphic rooted vegetation. Group: Temperate Subgroup: (N.) Natural/Semi-natural Formation: a. Non-tidal Hydromorphic rooted vegetation. Floristic level (1) Alliance Floristic level (2) Plant Association (Dominance type) Riverine System-Upper Perennial Persistent-Emergent Wetlands (Dominance type) Riverine System-Upper Perennial Persistent-Emergent Wetlands (Dominance type) ______________________________________________________________________________ 17 A CLASSICATION OF RIPARIAN WETLAND PLANT ASSOCIATIONS A classification of natural, native riparian vegetation has been developed for Colorado. This classification is based entirely on data collected in the field, between 1990 and 1998. Field sites were chosen to represent the diversity of habitats available in Colorado (see Method section for more information). The table below lists the 150 plant associations developed and described in this classification. A full description of each association can be found on the 3.5” floppy disk included in this report. See the table below for the corresponding file name. See Figure 1, for a map of Colorado and the 1880 plot locations. A Field Key to the associations is located in Appendix 1. Example field forms and the manual to the forms used are located in Appendix 2. A list of location, rank, and plant association for 1883 plots is located in Appendix 3. List of Riparian Wetland Plant Associations of Colorado. (See page 23 for Global and State Rank Definitions). CNHP Element Code State Name Global Rank State Rank CCA Filename (see enclosed floppy disk) CONIFEROUS FORESTS CRFEXXXXX1 Abies concolor-(Picea pungens)-Populus angustifolia/Acer glabrum G2 S2 abcopipu.doc CRFEABLA0B Abies lasiocarpa-Picea engelmannii/Alnus incana ssp. tenuifolia G5 S5 ablaalin.doc CRFEABLA0A Abies lasiocarpa-Picea engelmannii/Calamagrostis canadensis G5 S3 ablacaca.doc CRFCABLA0I Abies lasiocarpa-Picea engelmannii/Carex aquatilis G3 S3 ablacaaq.doc CRFFPIEN0A Abies lasiocarpa-Picea engelmannii/Equisetum arvense G5 S2 ablaeqar.doc CRFEABLA0B Abies lasiocarpa-Picea engelmannii/Mertensia ciliata G5 S5 ablameci.doc CRFFABLA0B Abies lasiocarpa-Picea engelmannii/Ribes spp. G5 S3 ablarisp.doc CRFEABLA0F Abies lasiocarpa-Picea engelmannii/Salix drummondiana G5 S4 ablasadr.doc CRFEXXXXX7 Abies lasiocarpa-Picea engelmannii-Populus angustifolia/Lonicera involucrata G4 S3 ablapoan.doc CWBAJUSC1A Juniperus scopulorum/Cornus sericea G4 S2 junsccose.doc CRFEPIPU0A Picea pungens/Alnus incana ssp. tenuifolia G3 S3 pipualin.doc CRFAPIPU1A Picea pungens/Betula occidentalis G2 S2 pipubeoc.doc CRFEPIPU0G Picea pungens/Cornus sericea G4 S2 pipucose.doc List of Riparian Plant Associations for Colorado, Continued. 18 CRFEPIPU0H Picea pungens/Equisetum arvense G3? S2? pipueqar.doc CEGL002638 Pinus ponderosa/Alnus incana ssp. tenuifolia G2 S2 pipoalin.doc CWFAPSME1B Pseudotsuga menziesii/Betula occidentalis G3? S3 psmebeoc.doc CRFEPSME0A Pseudotsuga menziesii/Cornus sericea G4 S2 psmecose.doc CWFAPSME0B Pseudotsuga menziesii/Quercus gambelii G5 S4 psmequga.doc CWFAPSME0C Pseudotsuga menziesii/Symphoricarpos oreophilus G5 S4 psmesyor.doc MIXED DECIDUOUS-CONIFEROUS FORESTS CRFEXXXX6 Populus angustifolia-Picea pungens/Alnus incana G3 S3 popialin.doc CRFEPOAN4A Populus angustifolia-Juniperus scopulorum G2G3 S2 poanjusc.doc CRFDPOAN3M Populus angustifolia-Pseudotsuga menziesii G2? S2 poanpsme.doc DECIDUOUS FORESTS CWFDACNE2B Acer negundo/Betula occidentalis G1G2 S1 acnebeoc.doc CWFDACNE2C Acer negundo/Cornus sericea G3? S2 acnecose.doc CWFDACNE2D Acer negundo/Prunus virginiana G3 S2 acneprvi.doc CWFDACNE2F Acer negundo-Populus angustifolia/Celtis reticulata G1Q S1Q acpocere.doc CWFDACNE2A Acer negundo-Populus angustifolia/Cornus sericea G2 S2 acpocose.doc CCNHPXXX11 Populus angustifolia Sand Dune Forest G1 S1 poansand.doc CWFDPOAN3K Populus angustifolia/Alnus incana ssp. tenuifolia G3? S3 poanalin.doc CWFDPOAN3I Populus angustifolia/Betula occidentalis G3? S2 poanbeoc.doc CWFDPOAN3H Populus angustifolia/Cornus sericea G4 S3 poancose.doc CWFDPOAN3E Populus angustifolia/Crataegus rivularis G2? S2? poancrri.doc CCNHPXXX27 Populus angustifolia/mixed Salix species G3 S3 poanmixsalixspp.d oc CRFEPOAN5A Populus angustifolia/Prunus virginiana G2G3 S1 poanprvi.doc CWFDPOAN3G Populus angustifolia/Rhus trilobata G3 S3 poanrhtr.doc CCNHPXXXX2 Populus angustifolia/Salix drummondiana-Acer glabrum G1? S1? poansadr.doc CWFDPOAN3F Populus angustifolia/Salix eriocephala var. ligulifolia- Shepherdia argentea G1 S1 poansali.doc CWFDPOAN3C Populus angustifolia/Salix exigua G4 S4 poansaex.doc List of Riparian Plant Associations for Colorado, Continued. 19 CRFDPOAN3N Populus angustifolia/Salix irrorata G2? S2 poansair.doc CCNHPXXXX3 Populus angustifolia/Salix lucida var. caudata G1Q S1Q poansalu.doc CWFDPOAN3M Populus angustifolia/Symphoricarpos spp. G2Q S2Q poansyal.doc CRFAPOBA0A Populus balsamifera GU SU poba.doc CPFAPODE3B Populus deltoides /Panicum virgatum G1G2 S1 podepavi.doc CPFAPODE3C Populus deltoides ssp. monilifera-(Salix amygdaloides)/Spartina pectinata G1G2 S1 podesppe.doc NOT TRACKED Populus deltoides ssp. monilifera/Bromus inermis NA NA podebrin.doc CPFAPODE3E Populus deltoides ssp. monilifera/Carex lanuginosa G1? S1 podecala.doc CEGL000678 Populus deltoides ssp. monilifera/Muhlenbergia asperifolia G2Q S1Q podemuas.doc CPFDPODE3G Populus deltoides ssp. monilifera/Prunus virginiana G1Q S1Q podeprvi.doc CPFAPODE3D Populus deltoides ssp. monilifera/Symphoricarpos occidentalis G2G3 S2 podesyoc.doc CWFDPODEWA Populus deltoides ssp. wislizenii/Rhus trilobata G2 S2 poderhtr.doc CCNHPXXX19 Populus deltoides/Pascopyron smithii-Panicum obtusum G1G2Q S1S2 Q podepasmpaob.do c CPFAPODE3A Populus deltoides/Salix exigua G4? S3 podesaex.doc CCNHPXXX16 Populus deltoides/Sporobolus airoides G2Q S2Q podespai.doc CCNHPXXX17 Populus deltoides/Sporobolus asper G1Q S1Q podespas.doc CCNHPXXX18 Populus deltoides/Sporobolus cryptandrus G1G2Q S1S2 Q podespcr.doc CEGL000944 Populus fremontii/Salix goodingii G2 S1 pofrsago.doc CRFEPOTRTA Populus tremuloides/Acer glabrum G2 S1S2 potracgl.doc CRFFPOTRTK Populus tremuloides/Alnus incana ssp. tenuifolia G3 S3 potralin.doc CEGL000648 Populus tremuloides/Betula occidentalis G2G3 S2 potrbeoc.doc CRFEPOTRTF Populus tremuloides/Cornus sericea G3 S2S3 potrcose.doc CRFFPOTRTG Populus tremuloides/Tall forb G5 S5 potrtafo.doc SHRUBLANDS CRSAALIN2A Alnus incana ssp. tenuifolia/Equisetum arvense G3? S3 alineqar.doc CWSFALIN0B Alnus incana ssp. tenuifolia/Mesic forb G3G4Q S3 alinmefo.doc CRSAALIN2C Alnus incana ssp. tenuifolia/Mesic graminoid G5Q S3 alinmegr.doc CWSFALIN0C Alnus incana ssp. tenuifolia-Cornus sericea G3G4 S3 alincose.doc CWSFALIN0A Alnus incana ssp. tenuifolia-mixed Salix species G3 S3 alinsal.doc CRSAALIN0C Alnus incana ssp. tenuifolia-Salix drummondiana G3 S3 alinsadr.doc CWSDARTRTB Artemisia tridentata/Leymus cinereus G2G3 S1 artrleci.doc CCNHPXXX23 Baccharis salicina G1G2Q S1S2 Q bacsal.doc CRSABEGL1A Betula glandulosa/Mesic forb-Mesic graminoid G3G4 S3 beglmefo.doc CRSABEOCOA Betula occidentalis/Mesic forb G3 S2 beocmefo.doc CRSABEOC0B Betula occidentalis/Mesic graminoid G3 S2 beocmegr.doc CCNHPXXX21 Celtis laevigata var. reticulata G1G2Q S1S2 Q cela.doc List of Riparian Plant Associations for Colorado, Continued. 20 CWSFCOSE0A Cornus sericea G4 S3 cose.doc CWFAPSME1A Corylus cornuta G3 S1 coco.doc CRSACRRI0A Crataegus rivularis G2Q S2Q crri.doc CWSFFOPU0A Forestiera pubescens G1G2 S1 fopu.doc CWFEFRAN0A Fraxinus anomala/Quercus gambelii GUQ S1Q franquga.doc CRWAPEFL0A Pentaphylloides floribunda/Deschampsia cespitosa G4 S3S4 pefldece.doc CPSAPRVI0A Prunus virginiana G4Q S3 prvi.doc CWSEQUGA0B Quercus gambelii/Symphoricarpos spp. G5 S3S4 qugasysp.doc CWSFRHTR0A Rhus trilobata G2 S2 rhtr.doc CWSDSAVE4A Sarcobatus vermiculatus/Distichlis spicata G4 S1 savedisp.doc CWSFSHAR0B Shepherdia argentea G3G4 S1 shar.doc CWPSSYOC0A Symphoricarpos occidentalis G4G5 S3 syoc.doc CRWASABE2A Salix bebbiana/Mesic graminoid G3? S2 sabe.doc CRWASABO0B Salix boothii/Carex utriculata G4 S3 sabocaut.doc CRWASABO0D Salix boothii/Mesic forb G3 S3 sabomefo.doc CRWASABR0C Salix brachycarpa/Carex aquatilis G2G3 S2S3 sabrcaaq.doc CRWASABR0B Salix brachycarpa/Mesic forb G4 S4 sabrmefo.doc CRWASADR0A Salix drummondiana/Calamagrostis canadensis G3 S3 sadrcaca.doc CRWASABR0C Salix drummondiana/Carex aquatilis G2G3 S2S3 sadrcaaq.doc CRWASADR0D Salix drummondiana/Mesic forb G4 S4 sadrmefo.doc CRWASAER1A Salix eriocephala var. ligulifolia G2G3 S2S3 saer.doc CRWASAEX0B Salix exigua/Bare ground G5 S5 saexbagr.doc CRWASAEX0C Salix exigua/Mesic graminoid G5 S5 saexmegr.doc CRWASAER1A Salix exigua-Salix eriocephala var. ligulifolia G2G3 S2S3 saexsaer.doc CRWASAGE2D Salix geyeriana/Calamagrostis canadensis G5 S3 sagecaca.doc CRWASAGE2E Salix geyeriana/Carex aquatilis G3? S3 sagecaaq.doc CRWASAGE2C Salix geyeriana/Carex utriculata G5 S3 sagecaut.doc CRWASAGE2F Salix geyeriana/Mesic forb G3 S3 sagemefo.doc CRWASAGE2B Salix geyeriana-Salix monticola/Calamagrostis canadensis G3 S3 sagesamocaca.doc CRWASAMO0A Salix geyeriana-Salix monticola/Mesic forb G3 S3 sagesamomefo.doc CRWASALU1A Salix lasiandra (var. caudata or var. lasiandra) G3Q S2S3 salu.doc CRWASAMO0B Salix monticola/Calamagrostis canadensis G3 S3 samocaca.doc CRWASAMO0E Salix monticola/Carex aquatilis G3 S3 samocaaq.doc CRWASAMO0D Salix monticola/Carex utriculata G3 S3 samocaut.doc CRWASAMO0C Salix monticola/Mesic forb G3 S3 samomefo.doc CRWASAMO0F Salix monticola/Mesic graminoid G3 S3 samomegr.doc CRWASAPL2F Salix planifolia/Calamagrostis canadensis G3 S3 saplcaca.doc CRWASAPL2G Salix planifolia/Caltha leptosepala G4 S4 saplcale.doc CRWASAPL2D Salix planifolia/Carex aquatilis G5 S4 saplcaaq.doc CCNHPXXX26 Salix planifolia/Mesic forb G4 S4 saplmefo.doc CRWASAWO0C Salix wolfii/Calamagrostis canadensis G3 S2S3 sawocaca.doc CRWASAWO0A Salix wolfii/Carex aquatilis G4 S3 sawocaaq.doc CRWASAWO0D Salix wolfii/Carex utriculata G4 S3 sawocaut.doc List of Riparian Plant Associations for Colorado, Continued. 21 CRWASAWO0B Salix wolfii/Mesic forb G3 S3 sawomefo.doc HERBACEOUS VEGETATION CPWAANGE0A Andropogon gerardii-Sorghastrum nutans G2 S1S2 angesonu.doc CCNHPXXX22 Bothriochloa springfieldii G1G2Q S1S2 Q bolato.doc CRWCCACA4A Calamagrostis canadensis G4Q S4 caca.doc CRWCCALE4A Caltha leptosepala G4 S4 cale.doc CRWECAC06A Cardamine cordifolia-Mertensia ciliata-Senecio triangularis G4 S4 cacomeci.doc CRWCCAAQ0A Carex aquatilis G5 S4 caaq.doc CRWCCAAQ0B Carex aquatilis–Carex utriculata G4 S4 caaqcaut.doc CRWCCALA3A Carex lanuginosa G3? S3 carlan.doc CRWACAMI0A Carex microptera G4 S2? cami.doc CPWCCANE2A Carex nebrascensis G4 S3 cane.doc CRGBCAPR1A Carex praegracilis G3 S2 capr.doc CRWCCASA0A Carex saxatilis G3 S2 casa.doc CRWECASC7B Carex scopulorum-Caltha leptosepala G4 S4 casccale.doc CPWCCASI0A Carex simulata G4 S1 carexsimulata.doc CRWCCARO6A Carex utriculata G5 S4 caut.doc CRWECAVE5A Carex vernacula GU SU carver.doc CRWACAVE0A Carex vesicaria G2 S1 cave.doc CRGBDECE0F Deschampsia cespitosa G4? S4 dece.doc CPWBDIST0A Distichlis spicata var. spicata G5 S3 disp.doc CWWAELPA3A Eleocharis palustris G5 S4 elepal.doc CRFEABLA0E Eleocharis quinqueflora G4 S3S4 elqu.doc CWWAJUBA0A Juncus balticus var. montanus G5 S5 juba.doc CWWCMUAS0A Muhlenbergia asperifolia G3? S3? muas.doc CEGL001573 Panicum obtusum-Buchloe dactyloides G?Q S1S2 Q paobbuda.doc CPGAAGSM0B Pascopyrum smithii-Bouteloua gracilis G5 S4 passmi.doc CWWBPHCO1A Phragmites australis G4 G3 phau.doc CPWDSCTA0A Scirpus acutus-Scirpus tabernaemontani G3 S2S3 scacscta.doc CPWDSCMA0A Scirpus maritimus G4 S2 scma.doc CWINBSCU0A Scirpus pungens G3G4 G3 scpu.doc CWWCSPGR0A Spartina gracilis GU SU spagra.doc CWWCSPPE0A Spartina pectinata G3? S1 spapec.doc CPWBSPAI0A Sporobolus airoides G3Q S3 spoair.doc CPWDTYAN0A Typha angustifolia-Typha latifolia G5 S3 tyantyla.doc 22 Colorado Natural Heritage Program's Element and Occurrence Ranks Global rarity ranks (G) refer to a species' rarity throughout it range, state rarity ranks (S) refer to a species’ rarity throughout the state. Note that GA and GN are not used and GX means extinct. These ranks should not be interpreted as legal designations. Rarity Ranks (applied to an element only) G/S1 Critically imperiled; usually 5 or fewer occurrences in the state; or may be a few remaining individuals; often especially vulnerable to extirpation. G/S2 Imperiled; usually between 5 and 20 occurrences; or with many individuals in fewer occurrences; often susceptible to becoming endangered. G/S3 Vulnerable; usually between 20 and 100 occurrences; may have fewer occurrences, but with a large number of individuals in some populations; may be susceptible to large-scale disturbances. G/S4 Common; usually > 100 occurrences, but may be fewer with many large populations; may be restricted to only a portion of the state; usually not susceptible to immediate threats. G/S5 Very common; demonstrably secure under present conditions. G/SU Status uncertain, often because of low search effort or cryptic nature of the element. T Trinomial, specifies the rank of that species and sub species. S#B Refers to the breeding season imperilment of elements that are not permanent residents. S#N Refers to the non-breeding season imperilment of elements that are not permanent residents. Where no consistent location can be discerned for migrants or non-breeding populations, a rank of ZN is used. SZ Migrant whose occurrences are too irregular, transitory, and/or dispersed to be reliably identified, mapped, and protected. SH Historically known from the state, but not verified for an extended period, usually > 15 years; this rank is used primarily when inventory has been attempted recently. SR Reported to occur in the state, but unverified. S3S4/G3G4 Watchlisted: Specific occurrence data are collected and periodically analyzed to determine whether more active tracking is warranted. Watchlisted species are noted in the lists by an asterisk (*) next to the species name. Notes: When a question mark follows a numerical rank (e.g., S2?), it indicates uncertainty about the accuracy of this rank. When two numbers appear in a state or global rank (e.g., S2S3), the actual rank of the elements falls between the two numbers. When a ‘Q’ follows a rank, it indicates uncertainty about the taxonomic status of the element. 23 BASIN BY BASIN SUMMARY The following section has, in alphabetical order, a summary of each study area (watershed or National Forest) significant riparian biodiversity and high quality riparian area locations. A list of the best condition reaches found is included to serve as Reference Reaches for each area. The table below is a list of the study areas, the year field data was collected, and the corresponding interim report. Study Area Year(s) Field Data Collected Interim Report Arkansas River Basin 1995, 1998 Kittel et al. 1996 Colorado River Basin 1993 Kittel et al. 1994 Gunnison River Basin 1994 Kittel et al. 1995 Lower San Juan River Basin 1998 Kittel et al. 1999b North Platte River Basin 1998 Kittel et al. 1999b Rio Grande and Closed Basins 1997 Kittel et al. 1999a Rio Grande National Forest** 1995 Kittel et al. 1999a Routt National Forest* 1993, 1994 Kettler and McMullen 1996 San Miguel and Dolores River Basin 1991 Kittel and Lederer 1993 San Juan National Forest* 1993, 1994, 1995 Richard et al. 1996 South Platte River Basin 1995, 1996 Kittel et al. 1997 White River Basin 1992 Kittel et al. 1994 Yampa River Basin 1990, 1991 Kittel et al. 1993 *National Forests were surveyed under individual contracts, and were conducted independently of the basin-wide surveys. The data were collected by the same field methods. **Rio Grande National Forest data was incorporated into the 1997 basin-wide survey field work, data analyses, and report. Additional quantitative data collected by the Heritage Program used in the development of the classification. Kittel, G. M. 1994. Montane riparian vegetation in relation to elevation and geomorphology along the Cache la Poudre River, Colorado. Thesis. University of Wyoming, Laramie, WY. Sanderson and Kettler. 1996. A preliminary wetland vegetation classification for a portion of Colorado’s West Slope. Report submitted to the Colorado Department of Natural Resources and the U.S. Environmental Protection Agency. Colorado Natural Heritage Program, Colorado State University, Ft. Collins, CO. Sanderson, J. and M. March. 1996. Extreme rich fens of South Park, Colorado: their distribution, identification, and natural heritage significance. Report submitted to Park County, the Colorado Department of Natural Resources, and the U.S. Environmental Protection Agency. Colorado Natural Heritage Program, Colorado State University, Ft. Collins, CO. Culver, D. R., M. A. March, S. M. Kettler, C.A. Pague. et al. 1996. Natural heritage inventory of significant animals and plants and classification of riparian associations, Timpas Grazing District and Kim Grazing Association, Pike-San Isabel National Forest, Cimarron and Comanche National Grasslands. Natural Heritage Technical Report #96-1. Colorado Natural Heritage Program, Colorado State University, Ft. Collins, CO. 24 Arkansas River Basin The Arkansas watershed has several excellent condition foothill riparian with relatively rare (at least state rare) plant associations. These include the river birch/mesic forb (Betula occidentalis/mesic forb) (G3/S2) and hazelnut (Corylus cornuta) (G3/S1) shrublands, and the narrowleaf cottonwood/river birch (Populus angustifolia/Betula occidentalis) (G3?/S2) and narrowleaf cottonwood-Douglas fir (Populus angustifolia-Pseudotsuga menziesii) (G2?/S2) woodlands. Several excellent condition examples of these types were located in the Rampart Range. Steep canyon walls and a desert-like climate provide difficult access for recreation and low forage production for livestock, allowing some riparian areas to remain undisturbed for much of the growing season. The best sites in the upper Arkansas area were not grazed or only lightly grazed, and were areas off-limits to all-terrain vehicular use. Several new riparian plant associations were discovered in the lower (plains) Arkansas watershed. Six new plains cottonwood associations, one new herbaceous association and one new riparian shrubland were discovered and are described in the Community Characterization Abstracts. New associations are listed below: Newly described Riparian Plant Associations from the Lower Arkansas River Basin Global Rank State Rank Celtis laevigata var. reticulata G1G2 S1S2 Baccharis salicina G1G3 S1S2 Bothriochloa springfieldii G1G2 S1S2 Populus fremontii/Salix gooddingii G2 S1 Populus deltoides/Muhlenbergia asperifolia G2Q S1Q Populus deltoides/Pascopyron smithii-Panicum obtusum G1G2 S2 Populus deltoides/Sporobolus asper G1Q S1Q Populus deltoides/Sporobolus cryptandrus G1G2 S1S2 Nearly the entire mainstem of the Arkansas River is choked with the invasive, non-native shrub/tree, Tamarix ramnossima (tamarisk, salt cedar). The bedrock geology of the Arkansas River is siltstone and limestone, making the soil and water naturally basic. Control of the river flow and irrigation return flows have significantly altered the ecology of the Arkansas River. Tamarisk can better thrive and out-compete the native cottonwoods and grasses under these altered conditions. Luckily, a few stands of relict native riparian vegetation were found, and restoration efforts to remove the tamarisk are underway, giving a limited view of the potential natural riparian vegetation of the lower Arkansas River basin. Many high quality examples of common riparian associations were observed in the upper watershed (see table below). The best sites located in 1995 and 1998 by CNHP Riparian Crew are listed below. While not all streams and rivers in the watershed were surveyed, the following locations can be used as Reference Reaches for the Arkansas River Watershed. This list is restricted to only A ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. 25 REFERENCES REACHES of the ARKANSAS RIVER BASIN Plot # Owner SURVEYSITE County Elev. feet LAT LONG Site Conditi on Rank Plant Association 95AM14 BLM Unnamed tributary to Badger Creek Fremont 7080 38.49 105.84 A Populus angustifolia-Juniperus scopulorum 95AM19 STATE PARK/ DOW Four mile Creek at Dome Rock Teller 8200 38.84 105.23 A Salix geyeriana-Salix monticola/Mesic Forbs 95AM31 BLM East Beaver Creek Fremont 6600 38.61 105.02 A Populus angustifolia-Pseudotsuga menziesii 95AM34 BLM East Fork Arkansas River Lake 10240 39.33 106.22 A Salix eriocephala var. ligulifolia 95AM39 BLM Iowa Gulch (upper) Lake 11400 39.23 106.20 A Salix wolfii/Carex aquatilis 95AM53 BLM Little Cottonwood Creek at Brown's Canyon Chaffee 7800 38.75 106.05 A Populus angustifolia-Pseudotsuga menziesii 95AM54 BLM Green Creek Chaffee 8280 38.51 106.18 A Populus angustifolia-Juniperus scopulorum 95RR04 BLM Beaver Creek-just below E-W confluence Fremont 6480 38.60 105.02 A Betula occidentalis/Mesic Forbs 95RR07 BLM Four mile Creek above Long Gulch Fremont 6280 38.62 105.22 A Salix exigua/Bare Ground 95RR15 BLM Felch Creek Fremont 7000 38.55 105.17 A Populus angustifolia/Prunus virginiana 95RR16 BLM Cripple Creek Teller 7950 38.69 105.21 A Unclassified: Populus acuminata 95RR19 STATE Four mile Creek at Cabin Creek Teller 8300 38.84 105.21 A Betula occidentalis/Mesic Forb 95RR20 BLM Wilson Creek Teller 7280 38.67 105.17 A Populus angustifolia/Salix irrorata 95RR27 BLM Grape Creek at Isinglass Gulch Fremont 6550 38.32 105.35 A Juniperus scopulorum/mesic graminoid 98DZ01 USFS Stout Creek at Bushnell Lakes Fremont 9480 38.37 105.86 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 98DZ02 USFS Middle Taylor creek at Hermit Peak Custer 10400 38.10 105.62 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 98DZ04 USFS South Colony creek at Rainbow trail Custer 9620 37.99 105.49 A Alnus incana/Mesic Forbs 98GK01 Private Rock Basin Lincoln 4640 38.77 103.28 A Eleocharis palustris 98GK02 Private Rock Basin Lincoln 4640 38.77 103.28 A Pascopyron smithii Grassland 98GK08 Private Big Sandy at Arroyo Cheyenne 4540 38.84 103.13 A Populus deltoides subsp. monilifera/Panicum virgatum 98LT03 State/U SFS Arkansas River at the Numbers boating put in. Chaffee 8600 39.00 106.21 A Populus angustifolia-Pseudotsuga menziesii 98LT05 USFS Middle Cottonwood creek about 2.5 miles below Cottonwood Pass Chaffee 10940 38.80 106.42 A Betula glandulosa/Mesic Forbs-Mesic Graminoids 98LT06 USFS South Cottonwood creek at Sheep Mountain Chaffee 9320 38.79 106.26 A Populus tremuloides/Acer glabrum 98MD05 USFS Two creek at Badger creek Fremont 8800 38.61 105.81 A Alnus incana/Mesic Forbs 98MD06 USFS Middle Cottonwood creek about 2.5 miles below Cottonwood Pass Chaffee 10940 38.80 106.42 A Betula glandulosa/Mesic Forbs-Mesic Graminoids 98MD07 USFS Middle Cottonwood creek above North Fork Chaffee 10920 38.80 106.39 A Salix planifolia/Carex aquatilis 98MD08 USFS South fork of Clear creek below Virginia Peak Chaffee 10560 38.96 106.46 A Salix planifolia/Carex aquatilis 98MD11 USFS South Prong at Table Mountain Fremont 8120 38.32 105.82 A Populus angustifolia/Betula occidentalis 98MD14 USFS Middle Fork of the South Arkansas at Vulcan Mountain Chaffee 10200 38.56 106.31 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 98MD15 USFS Dry Creek at Little Horn Peak Custer 9040 38.05 105.54 A Populus tremuloides/Tall Mesic Forbs 98MD16 USFS Grape creek at Snowslide Mountain Custer 9300 37.93 105.62 A Populus tremuloides/Alnus incana 98MD17 USFS Beaver creek at Cisneros trailhead Custer 9000 37.98 105.08 A Populus tremuloides/Alnus incana 98MD18 USFS Cucharas creek at Blue Lakes Huerfano 10560 37.31 105.15 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 98MD19 USFS Unnamed tributary of Wahatoya creek at Wahatoya camp. Huerfano 8600 37.41 104.97 A Abies concolor-Picea pungens-Populus angustifolia/Acer glabrum 26 Colorado River Basin The Colorado River basin covers a wide diversity of riparian habitats, and consequently, a wide number of plant associations occur within this watershed. The diversity represents the Colorado Plateau and Southern Rocky Mountain Ecoregions. Because much of the state is dominated by the Southern Rocky Mountain ecoregion, only one riparian association was unique to the Colorado River basin. The single-leaf ash (Fraxinus anomala) shrubland (GUQ/S1Q) occurs only in desert canyons and arroyos, a representative of the Colorado Plateau Ecoregion. It was sampled only once in a dry tributary near Grand Junction. More stands probably occur in draws and arroyos in the far western part of the state, and the association is expected to continue into Utah. The Colorado River basin does contain some fair and good condition stands of some of Colorado’s rarest riparian types. Along the main stem of the Colorado River below Glenwood Springs, are fine examples of the globally rare narrowleaf cottonwood/skunk brush (Populus angustifolia/Rhus trilobata) (G3/S3) and the Rio Grande cottonwood/Skunk brush (Populus deltoides ssp. wislizenii/Rhus trilobata) (G2/S2) riparian woodlands. Unfortunately, while some of the best stands in the state, they cannot be called A-ranked because the hydrology of the Colorado River has been significantly altered from historic flow patterns. One association, the box elder/chokecherry (Acer negundo/Prunus virginiana) type (G3/S2), has the center of its distribution in the Colorado watershed, in and around the Roan Plateau. It is known only from the Colorado and White River basins. Several high quality, if more common, riparian associations were located within the watershed. Three locations stand out for their large size and pristine riparian and surrounding upland areas. 1) Parachute Creek, on the Roan Plateau, had many unusual and excellent quality riparian associations, and several rare plant species; 2) Deep Creek, draining the Flat Tops Wilderness Area, has an excellent example of a montane river ecosystem without roads or other developments, and 3) Paradise Creek, on the western side of Rocky Mountain National Park, is one of the most pristine and untouched subalpine watersheds known to CNHP ecologists. Few of the riparian plant associations located in these sites are rare, however they are without questions some of the finest examples of functioning Colorado Plateau and Southern Rocky Mountain riparian ecosystems in the state (see locations and plant association names in the table below). The following list indicates the location of the best examples of riparian associations found by the CNHP riparian team in 1993. While not every stream and river in the watershed was surveyed, this list can be used as a list of References Reaches for the Colorado River Basin. This list is restricted to only A ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. REFERENCE REACHES of the COLORADO RIVER BASIN Plot # Owner SURVEYSITE County Elev. feet LAT LONG Site Conditio n Rank Plant Association 93DR05 USFS EAST BRANCH UPPER VASQUEX CREEK Grand 10440 39.81 105.83 A Salix planifolia/Carex aquatilis 93DR06 RMNP UPPER CO RIVER, LITTLE YELLOWSTONE CANYON Grand 9550 40.46 105.81 A Salix drummondiana/Mesic Forbs 93DR12 BLM MUDDY CREEK AREA CAMP Grand 7720 40.18 106.38 A Unclassified: Carex foenea Alliance 93DR13 BLM SULPHER GULCH Grand 7550 40.09 106.27 A Scirpus pungens 93DR15 Private SULPHER SPRINGS Grand 7750 40.09 106.27 A Scirpus pungens 27 93DR17 USFS UPPER CATARACT CREEK Eagle 10950 39.43 106.25 A Salix planifolia/Caltha leptosepala 93DR20 USFS WEST CROSS CREEK Eagle 10190 39.46 106.51 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 93GK02 Private CONN CREEKABOVE CASCADE CANYON Garfield 6280 39.51 108.24 A Acer negundo/Prunus virginiana 93GK05 BLM/Pri vate LEFT FORK CARR CREEK Garfield 6560 39.56 108.53 A Populus angustifolia/Rhus trilobata 93GK20 Private East Middle Fork Parachute Creek GARF 6800 39.62 108.06 A Populus angustifolia/Cornus sericea 93GK21 Private East Middle Fork Parachute Creek GARF 6800 39.62 108.06 A Populus angustifolia/Betula occidentalis 93GK22 Private East Middle Fork Parachute Creek GARF 6800 39.62 108.06 A Acer negundo/Prunus virginiana 93GK44 USFS WEST FORK RED DIRT CREEK Eagle 9720 39.84 107.08 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 93GK45 USFS MIDDLE FORK DERBY CREEK Garfield 10680 39.94 107.16 A Salix planifolia/Caltha leptosepala 93GK46 USFS DRY SWEETWATER CREEK (LOWER) Garfield 8880 39.82 107.24 A Abies lasiocarpa-Picea engelmannii/Ribes spp. 93RR02 Private CONN CREEK (UPPER) Garfield 6560 39.51 108.25 A Acer negundo/Prunus virginiana 93RR07 BLM HUNTER CANYON Mesa 5825 39.34 108.57 A Pseudotsuga menziesii/Quercus gambelii 93RR08 BLM HUNTER CANYON Mesa 5640 39.34 108.57 A Fraxinus anomala 93RR18 BLM- NAVAL OIL SHALE EAST FORK FALLS Garfield 7120 39.57 108.02 A Acer negundo-Populus angustifolia/Cornus sericea 93RR48 BLM CO R @ JACKFLATS Eagle 6380 39.81 106.96 A Populus angustifolia-Juniperus scopulorum 93RR53 USFS DEEP CRK-CLARK RIDGE Garfield 8720 39.79 107.57 A Salix monticola/Carex utriculata 93RR57 USFS SAINT JOHN CREEK Summit 10740 39.57 105.88 A Salix planifolia/Caltha leptosepala 93RR59 RMNP TIMBER CREEK-RMNP Grand 9400 40.38 105.84 A Picea pungens/Alnus incana 93RR60 RMNP LULU CRK Grand 10250 40.46 105.86 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 93RR61 RMNP PARADISE CREEK Grand 9600 40.23 105.74 A Calamagrostis canadensis 93RR63 USFS KEYSER CRK AT SIMPSON CRK Grand 9180 39.91 106.01 A Salix wolfii/Carex aquatilis 93RR64 USFS TROUT CREEK Grand 8920 40.32 106.04 A Salix wolfii/Carex utriculata 93RR65 USFS FALL CREEK Eagle 9520 39.51 106.42 A Salix wolfii/Carex utriculata 93RR66 USFS FALL CREEK Eagle 9520 39.51 106.42 A Carex utriculata 93SS07 USFS Deep Creek-Ballixbury Spring Garfield 8320 39.72 107.19 A Cornus sericea 93SS08 USFS Deep Creek-Mayres Spring Garfield 8280 39.72 107.19 A Cornus sericea 93SS11 USFS Bull Lake Stream Garfield 10280 39.94 107.12 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 93SS12 USFS Middle Fork Derby Creek Garfield 9740 39.90 107.12 A Salix planifolia/Carex aquatilis 93SS13 USFS Middle Fork Derby Creek Garfield 9740 39.90 107.12 A Carex utriculata 93SS20 USFS South Fork Ranch Creek Grand 10120 39.90 105.73 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 93SS24 NPS North Inlet Grand 9200 40.29 105.74 A Carex aquatilis-Carex utriculata 93SS25 NPS Colorado River in Kawuneechee Valley Grand 8760 40.32 105.86 A Salix geyeriana/Calamagrostis canadensis 93SS27 USFS BAKER GULCH Garfield 10760 40.39 105.92 A Eleocharis quinqueflora 93SS28 USFS WILLIANS FORK AT KINNEY CREEK Grand 8800 39.83 106.05 A Salix geyeriana/Carex utriculata 93SS33 USFS BUCKHORN CREEK Grand 9120 40.24 106.29 A Alnus incana/Mesic Forb 93SS37 BLM BERRY CREEK Eagle 8320 39.67 106.57 A Salix drummondiana/Mesic Forbs 93SS39 USFS THIRD GULCH Eagle 9560 39.55 106.83 A Salix drummondiana/Mesic Forbs 93SS46 USFS S. FRK. RED SANDSTONE CRK Eagle 11120 39.71 106.34 A Carex scopulorum-Caltha leptosepala 93SS47 USFS S. FRK. RED SANDSTONE CRK Eagle 11120 39.71 106.34 A Eleocharis quinqueflora 93SS48 USFS MITCHELL CRK Eagle 9920 39.39 106.32 A Salix planifolia/Carex aquatilis 93SS50 USFS TWO ELK CREEK Eagle 8160 39.57 106.39 A Alnus incana-Cornus sericea 28 Gunnison River Basin While no new plant associations were discovered in the Gunnison basin, several rare and unusual types were clarified, and phases of more common plant associations became apparent. One globally rare association, the narrowleaf cottonwood/strap leaf willow-buffaloberry (Populus angustifolia/Salix eriocephala var. ligulifolia-Shepherdia argentea) (G1/S1), previously known from only two sites, was found at two new locations. Unfortunately these occurrences are heavily degraded, occur below dams, and are currently or have been heavily utilized by livestock in the past. This plant association was once a common cottonwood forest of lower reaches of the Gunnison, Uncompahgre, and North Fork rivers (Baker 1984). The Uncompahgre Plateau stands out as a unique area of the Gunnison watershed for riparian diversity. Many of the roads accessing the Plateau run along mesa tops, leaving the floodplains below intact. The lower reaches of the Plateau are important harbors of disappearing low-elevation riparian ecosystems, for example, the Populus angustifolia/Rhus trilobata association appears to be restricted to lower reaches of the Uncompahgre Plateau (Kittel and Lederer 1993). Many of these lower reaches are over-grazed to some extent, but may be recoverable with different management practices. In addition, several stands dominated by Pseudotsuga menziesii were found along steep, north-facing drainages. These stands are similar to ones sampled in the San Miguel River watershed (Kittel and Lederer 1993). Willow associations thought to be limited to the northern part of the state were found in abundance in the Gunnison watershed. Booth's willow (Salix boothii) dominated shrublands were previously known only from the Yampa River basin, and were not found in the White or Colorado River watersheds (Kittel and Lederer 1993, Kittel et al. 1994). In the Gunnison basin, we found some of the largest Salix boothii willow-wetlands seen in the state. In addition, Salix monticola, Rocky Mountain willow, is a common species throughout the high, central regions of Colorado, forms large stands with other willows with the Gunnison River basin. The following list indicates the location of the best examples of riparian associations found by the CNHP riparian team in 1994. While not all streams and rivers in the basin were surveyed, the following list can be used as a list of References Reaches for the Gunnison watershed. This list is restricted to only A ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. REFERENCE REACHES for the GUNNISON RIVER BASIN Plot # Owner SURVEYSITE County Elev. feet LAT LONG Site Condition Rank Plant Association 94GK06 USFS Little Monitor & Monitor Creeks Montrose 6760 38.55 108.29 A Salix exigua/Mesic Graminoids 94GK07 BLM Curecanti Creek at bald Mountain Gunnison 9560 38.66 107.38 A Salix planifolia/Caltha leptosepala 94GK09 USFS Grouse Spring Creek at Snowline Ridge Gunnison 8720 38.91 107.24 A Populus tremuloides/Alnus incana 94GK14 USFS Fall Crk (upper) Hinsdale 11400 38.13 107.42 A Carex aquatilis 94GK18 USFS Slate River up stream of Crested Butte Gunnison 8920 38.90 107.01 A Salix geyeriana/Carex aquatilis 94GK32 Private Unnamed trib to Pass Crk @ Swampy Pass Gunnison 10080 38.80 107.15 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 94GK33 USFS Unnamed trib to Pass Crk @ Swampy Pass Gunnison 10080 38.80 107.15 A Salix planifolia/Caltha leptosepala 94GK47 USFS Red Creek (upper) Ouray 9190 38.12 107.59 A Abies lasiocarpa-Picea engelmannii/Alnus 29 incana 94JB03 USFS East Fork Escalante Creek Mesa 6775 38.55 108.41 A Populus angustifolia/Cornus sericea 94JB06 USFS Traver Creek Montrose 6360 38.48 108.21 A Populus angustifolia/Rhus trilobata 94JB10 BLM Curecanti Creek @ Dry Fork Gunnison 9020 38.63 107.37 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 94JB11 USFS Snowshoe Creek Gunnison 7080 39.92 107.29 A Populus angustifolia-Picea pungens/Alnus incana 94JB17 USFS Independence Gulch Hinsdale 9840 38.10 107.33 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 94JB19 USFS Slate R. below Pittsburg Gunnison 9160 38.95 107.05 A Carex aquatilis 94JB21 USFS Brush Creek Gunnison 10800 38.71 16.59 A Carex aquatilis 94JB24 USFS Lake Fork Cochetopa Crk Saguache 11600 37.97 106.83 A Salix planifolia/Caltha leptosepala 94JB25 USFS Cochetopa Creek Saguache 10500 37.99 106.83 A Carex aquatilis 94JB26 USFS Stewart Creek Saguache 10450 38.02 106.84 A Salix geyeriana/Mesic Forbs 94JB27 USFS Cathedral Creek Saguache 10200 38.08 106.99 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 94JB29 USFS Mysterious Creek @ American Flag Mtn. Gunnison 10760 38.91 106.71 A Salix planifolia/Caltha leptosepala 94JB30 USFS Red Mtn Crk, West Headwaters Fork Gunnison 10920 38.98 106.57 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 94JB32 USFS Waterloo Gunnison 11500 38.91 106.42 A Salix planifolia/Caltha leptosepala 94JB47 USFS Oben Creek Ouray 9680 38.09 107.59 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 94JB48 USFS Oben Creek Ouray 8400 38.10 107.61 A Abies lasiocarpa-Picea engelmannii/Alnus incana 94JB49 USFS East Fork Dallas Crk. Ouray 9760 38.02 107.81 A Carex utriculata 94MD04 USFS Roubideau Creek @ Transfer Trail Montrose 7560 38.41 108.19 A Populus angustifolia-Picea pungens/Alnus incana 94MD14 USFS Fall Creek at Falls Gunnison 11160 38.16 107.42 A Calamagrostis canadensis 94MD15 USFS Firebox Creek (upper) Gunnison 10960 38.19 107.42 A Salix planifolia/Carex aquatilis 94MD27 USFS Mill Creek @ Castle view Gunnison 10360 38.70 107.14 A Salix drummondiana/Mesic Forbs 94MD29 USFS Flag Creek Gunnison 10280 38.88 106.73 A Salix boothii/Mesic Forbs 94MD30 USFS Bowman Creek Gunnison 10180 39.00 106.70 A Salix planifolia/Carex aquatilis 94MD38 USFS Porphyry Creek Gunnison 9200 38.48 106.38 A Alnus incana/Mesic Forbs 94RR01 USFS Big Dominguez Crk @ Carson Hole Mesa 7560 38.74 108.60 A Betula occidentalis/Mesic Forbs 94RR08 BLM Roubideau Creek at Bull Creek Montrose 6680 38.45 108.19 A Betula occidentalis/Mesic Forbs 94RR13 USFS Anthracite Creek at Dark Canyon Gunnison 6880 38.96 107.25 A Populus angustifolia/Alnus incana 94RR15 USFS East Soap Creek Gunnison 9000 38.68 107.26 A Abies lasiocarpa-Picea engelmannii/Alnus incana 94RR17 USFS Fall Creek @ water fall Gunnison 11160 38.16 107.42 A Salix planifolia/Carex aquatilis 94RR25 USFS Cascade Creek @Coal Creek Gunnison 7200 38.84 107.32 A Abies lasiocarpa-Picea engelmannii/Alnus incana 94RR30 USFS Brush Crk Gunnison 10800 38.71 106.60 A Salix planifolia/Carex aquatilis 94RR33 Private Lake Fork Cochetopa Creek Saguache 11360 37.98 106.81 A Carex aquatilis 94RR34 USFS Lake Fork Cochetopa Creek Saguache 11360 37.98 106.81 A Salix planifolia/Carex aquatilis 94RR35 USFS Pauline Creek Saguache 10920 38.08 106.90 A Carex aquatilis 94RR36 USFS West Brush Creek (upper) Gunnison 9550 38.92 106.88 A Carex utriculata 94RR39 USFS Waterloo Gulch Gunnison 11400 38.91 106.42 A Salix planifolia/Caltha leptosepala 94RR42 USFS E. Fk. Alder Crk @ Fossil Ridge Gunnison 10680 38.63 106.65 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 94RR47 USFS Porphyry Creek Gunnison 9400 38.48 106.37 A Alnus incana/Mesic Forbs 94RR50 USFS Red Creek Ouray 8240 38.12 107.62 A Populus angustifolia/Alnus incana 30 Lower San Juan River Basin One new plant association was discovered in the Lower San Juan Watershed, and three high quality occurrences of the rare (G1S1) Populus angustifolia/Salix eriocephala var. ligulifolia-Shepherdia argentea (narrowleaf cottonwood/strapleaf willow-silver buffalo berry) riparian woodland were documented in 1998 It was known previously from only four degraded stands (C and D rank) in the lower Gunnison and Uncompahgre watersheds. The new type, a Celtis laevigata var. reticulata (hackberry) riparian shrubland/woodland, was found along springs at the head of sandstone box canyons in Hovenweep National Monument. This community is more common further south in Arizona and New Mexico (Renee Rondeau, personal communication). Stands located in Colorado probably represent the northern-most extension of its range. Interestingly, the Celtis association was also located in the lower Arkansas River basin, on the far eastern edge of the state, as far south as possible without actually being in Oklahoma. While only two sites were considered to be in excellent condition (A-rank) within the study area, the B-rank (good) condition of the G1S1 riparian woodland mentioned above, it is the best known location in the state. In addition, several good occurrences (B-rank) of many other riparian types were located in the study area. Excellent (A-rank) and Good (B-rank) condition areas can be used as Reference Reaches for those habitats and riparian associations. This list is restricted to only A and B ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. REFERENCE REACHES of the LOWER SAN JUAN WATERSHED Plot Owner Survey Site County Township Range and Section Lat Long Rank Plant Association 98BG39 Southern Ute Indian Reservation Morgan Canyon La Plata T32N R13W Sec. 5 SE1/4 NE4/4 37 1 17 108 13 22 A Populus angustifolia/Rhus trilobata 98BG52 Hovenweep National Monument Cutthroat Castle at Hovenweep National Monument Montezum a T37N R19W Sec. 19 SE1/4 SW4/4 37 26 34 108 58 55 A Populus deltoides/Salix gooddingii 98BG33 Mesa Verde National Park School Section Canyon Montezum a T35N R15W Sec. 25 NE1/4 NW4/4 37 15 50 108 27 15 B Eleocharis palustris 98BG35 Mesa Verde National Park Echo Cliff Montezum a T34N R15W Sec. 20 NE1/4 SE4/4 37 9 56 108 29 43 B tamarix ramosissima 98BG36 Southern Ute Indian Reservation Los Pinos river at Rattlesnake Hill Archuleta T33N R7W Sec. 17 SE1/4 NE4/4 37 6 2 107 37 30 B Salix exigua/Mesic Graminoids 98BG37 Southern Ute Indian Reservation Los Pinos River at Rattlesnake Hill Archuleta T33N R7W Sec. 17 SE1/4 NE4/4 37 6 3 107 37 30 B Eleocharis palustris 98BG38 Southern Ute Indian Reservation Los Pinos river at Rattlesnake Hill Archuleta T33N R7W Sec. 17 SE1/4 NE4/4 37 6 2 107 37 32 B Populus angustifolia/Salix eriocephala var. ligulifolia-Shepherdia argentea 98BG41 Southern Ute Indian Reservation Los Pinos River at Rattlesnake Hill Archuleta T33N R7W Sec. 17 SE1/4 NE4/4 37 6 2 107 37 30 B Populus angustifolia/Salix eriocephala var. ligulifolia-Shepherdia argentea 31 98BG42 Southern Ute Indian Reservation La Plata river west of Breen La Plata T34N R11W Sec. 18 NW1/4 SE4/4 37 11 35 108 5 5 B Populus angustifolia/Betula occidentalis 98BG45 Southern Ute Indian Reservation Piedra river at Turkey creek Archuleta T33N R5W Sec. 2 SE1/4 NW4/4 37 7 50 107 21 40 B Salix exigua/Mesic Graminoids 98BG47 Southern Ute Indian Reservation San Juan river at Carracas Archuleta T32N R4W Sec. 23 SE1/4 Se4/4 37 0 27 107 16 20 B Shepherdia argentea 98BG51 Hovenweep National Monument Hackberry unit at Hovenweep National Monument Montezum a T36N R20W Sec. 2 Nw1/4 NE4/4 37 24 28 109 1 28 B Celtis laevigata 98BG54 Hovenweep National Monument Horseshoe Ruins at Hovenweep National Monument Montezum a T36N R20W Sec. 2 Nw1/4 SE/SW4/4 37 24 27 109 1 54 B Populus deltoides/Salix gooddingii 98DZ10 Southern Ute Indian Reservation Piedra river at Turkey creek Archuleta T33N R5W Sec. 2 SE1/4 NW4/4 37 7 50 107 21 40 B Populus angustifolia/Salix exigua 98BG40 Southern Ute Indian Reservation Johnson Canyon La Plata T32N R13W Sec. 5 NE1/4 NE4/4 37 2 23 108 13 24 B- Quercus gambelii 98DZ11 Southern Ute Indian Reservation San Juan river upstream of Navajo River Archuleta T32N R3W Sec. 2 SE1/4 SE4/4 37 2 52 107 8 12 B+ Populus angustifolia/Salix eriocephala var. ligulifolia-Shepherdia argentea 32 North Platte Watershed No new plant associations were discovered in the North Platte watershed in 1998. We focused on the valley floor, as some plots were taken on National Forest land in the upper watershed in 1993 and 1994 (see section on Routt National Forest). Two communities of interest, the Salix bebbiana (Bebb willow) riparian shrubland and the Salix boothii (Booth willow) riparian shrubland, were documented for the first time in the valley. These associations were expected to occur in the northern part of the state, and the North Platte watershed has plenty of habitat for these native, riparian shrublands. Overall the diversity of riparian areas observed in the watershed was about as expected for that part of the state. Much of the land visited was heavily utilized by livestock and consequently several sites were rejected for sampling. This negative interpretation may have been exacerbated by the unusually wet spring and the early sampling period (June 1998). While not all streams and rivers were surveyed in 1998, the following table indicated the location of some of the best riparian areas visited by CNHP riparian crews. High quality sites can serve as References Reaches for these plant associations in the North Platte watershed (see table below). This list is restricted to only A ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. REFERENCES REACHES of the NORTH PLATTE RIVER WATERSHED Plot Owner Survey Site Township Range and Section Lat Long Site Condition Rank Plant Association 98BG01 Routt NF Lone Pine Creek T10N R82W Sec. 22 NW1/4 NW4/4 40 45 49 106 36 27 A Alnus incana/Mesic Forbs 98BG02 Routt NF South Fork Hog Park Creek T12N R84W Sec. 26 NW1/4 NW4/4 40 59 26 106 50 16 A Salix drummondiana/Mesic Forbs 98BG04 CO State Forest Unnamed trib. St. Francis Creek T10N R78W Sec. 25 SW1/4 SE4/4 40 49 35 106 5 48 A Salix monticola/Calamagrostis canadensis 98BG05 Routt NF East Branch Willow Creek T5N R78W Sec. 15 Se1/4 SW4/4 40 23 43 106 7 47 A Salix bebbiana 98BG06 Routt NF East Branch of Willow creek near headwaters T5N R78W Sec. 33 NE1/4 NE4/4 40 22 14 106 8 36 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 98BG08 Routt NF Red Canyon downstream of confluence T9N R82W Sec. 34 NE1/4 SW4/4 40 42 19 106 35 45 A Calamagrostis canadensis 98BG09 Routt NF Red Canyon downstream of confluence. T9N R82W Sec. 34 NE1/4 SW4/4 40 42 19 106 35 45 A Salix drummondiana/Calamagrostis canadensis 98BG10 Routt NF Pinkham creek T11N R79W Sec. 13 NW1/4 SE4/4 40 55 18 106 12 15 A Populus tremuloides/Alnus incana 98BG11 Routt NF Pinkham creek T11N R79W Sec. 13 SW1/4 NW4/4 40 55 18 106 12 15 A Salix monticola/Mesic Forbs 98BG16 CO State Forest Kelly Creek T8N R77W Sec. 30 NW1/4 SE4/4 40 38 10 105 57 30 A Salix drummondiana/Mesic Forbs 98SS04 Routt NF Parkview Creek T5N R77W Sec. 23 NE1/4 SW4/4 40 23 6 106 5 15 A Salix geyeriana/Carex utriculata 33 98SS05 Mt. Zirkle Wilderness Area North fork of Roaring Fork creek T9N R82W Sec. 28 SE1/4 NE4/4 40 43 35 106 36 23 A Abies lasiocarpa-Picea engelmannii/Alnus incana 98SS08 Routt NF Middle Fork Arapaho Creek T5N R80W Sec 22 NW 1/4 40 23 36 106 21 37 A Abies lasiocarpa-Picea engelmannii/Alnus incana 98SS03 BLM Antelope Spring T8N R80W Sec. 24 SW1/4 NW4/4 40 38 55 106 19 40 A/B Carex aquatilis 34 Rio Grande and Closed Basin Watersheds A total of 70 plant associations were determined from over 200 sampled streams in the Rio Grande and Closed Basin watersheds This reflects the diverse array of habitats from high alpine meadows to the very unique alkaline playas on the San Luis Valley floor. Three new and one “resurrected” plant associations were discovered in the Closed Basin. The Populus angustifolia/Salix drummondiana-Acer glabrum (narrowleaf cottonwood/Drummond’s willow) is a new, globally rare plant association. It was discovered on one creek (Sand Creek), in a very large (over 4 continuous miles long) and pristine stand. This type has not been documented throughout the rest of Colorado. Further inventory is needed on the east flank of the Sangre de Cristo Mountains and in New Mexico. The Populus angustifolia (narrowleaf) Sand Dune Forest is also new and known only from the Closed Basin. This association is stands of old, mature cottonwoods (and nothing else) grows in sand dunes adjacent to Sand creek, just west of the eastern boarder of the Great Sand Dunes National Monument. It is a unique environmental setting. Shifting, wind-blown sand dunes, flooding, and channel migration are just a few of the annual disturbances this community must tolerate to survive. The cottonwoods occur in a series of bands, each slightly younger than the next. The oldest cottonwoods had huge trunks, few branches, and were about 40 feet tall. The youngest cottonwoods were only 2 feet tall and were a product of sucker shoots from the neighboring 10-20 feet tall cottonwoods. The Salix exigua-Salix eriocephala var. ligulifolia (coyote willow-strapleaf willow) shrubland was observed and described for the first time in 1997. It occurs along Trinchera and Sangre de Cristo Creeks in Costilla County. More stands were observed in 1998 along upper reaches of the Purgatory River, almost due east of stands located in the San Luis Valley on the other side of the Sangre de Cristo Mountains. The Abies concolor-Picea pungens-Populus angustifolia/Acer glabrum (white fir-blue spruce- narrowleaf cottonwood/Rocky Mountain maple) association was previously described by Baker (1986 and 1989) from the San Juan Mountains. This association had been lumped into the diverse riparian forest type called the Populus angustifolia-Picea pungens/Alnus incana (narrowleaf cottonwood-blue spruce/thin leaf alder) by Kittel et al. (1994). However, the lack of Alnus incana (thinleaf alder) and consistent presence of Abies concolor (white fir) and Acer glabrum (rocky mountain maple) in the Closed Basin and San Juan stands warrant splitting the type back out. Abies concolor (white fir) appears to be restricted to the southern part of the state, making the “new” association a flag for biodiversity of riparian areas in that part of the state. Excellent examples of all three can be seen on creeks draining the western flank of the Sangre de Cristo Mountains. Other interesting finds in the study area were: Colorado’s largest and most pristine stand of Sarcobatus vermiculatus/ Distichlis spicata (greasewood/saltgrass) on the San Luis Valley floor; the largest and most pristine example of the Populus angustifolia-Juniperus scopulorum (narrowleaf cottonwood-Rocky Mountain juniper) riparian woodland along Deadman Creek on 35 the Baca Ranch and a large example of a Carex simulata (analogue sedge) quaking fen along San Luis Creek in Saguache County. Only a handful of these fens occur in the state, and this one is very large and in very good condition. New riparian plant associations and exemplary examples of more common riparian communities found in the Rio Grande and Closed Basin watersheds, Colorado. Plant Associations Global State Creek Name, County, (Plot Numbers) Rank Rank Owner Abies concolor-Picea pungens-Populus angustifolia/Acer glabrum* G2 S2 Sand Creek, Saguache County (plots 97BG17 and 97GK27) RGNF/Private Populus angustifolia/Salix drummondiana-Acer glabrum* G1? S1? Sand Creek, Saguache Country (plots 97GK24-26) RGNF Populus angustifolia Sand Dune Forest* G1 S1 Sand Creek, Saguache and Alamosa Counties (plot 97MD11) Private Salix exigua-Salix eriocephala var. ligulifolia* G2G3 S2S3 Sangre de Cristo Creek, Costilla County (plots 97GK30-40) County Populus tremuloides/Betula occidentalis G2G3 S2 Rito Alto Creek, Saguache County (plot 97GK20) RGNF Cottonwood Creek, Saguache County (plot 97MD14) Private Populus angustifolia-Juniperus scopulorum G2G3 S2 Deadman Creek, Saguache County (plot 97GK12) Private Carex simulata G4 S2 San Luis Creek, Saguache County (plot 97GK18-19) Private La Jara Creek, Conejos County Plot (97EV32) State While not every stream and river in the basin was surveyed in 1995 and 1997, the following list can be used as list of References Reaches in the Rio Grande and Closed Basin watersheds. This list is restricted to only the A ranked stands sampled by CNHP riparian crews. Please consult the full list of all plots taken (Appendix 3) in this watershed for examples of other plant associations that may not be listed here. REFERENCE REACHES for the RIO GRANDE and CLOSED BASIN WATERSHEDS Plot # Owner SURVEYSITE County Elev. feet LAT LON G Site Conditi on Rank Plant Association 95RG04 USFS South Fork Rio Grande @ Highway Spgs. Rio Grande 8350 37.62 106.67 A Salix monticola/Calamagrostis canadensis 95RG08 USFS West Alder Creek Rio Grande 8400 37.72 106.66 A Alnus incana-Salix drummondiana 95RG09 USFS West Alder Creek Rio Grande 8400 37.72 106.66 A Alnus incana-Mixed Salix species 95RG10 USFS Trout Creek Mineral 9000 37.68 107.05 A Populus angustifolia-Picea pungens/Alnus incana 95RG11 USFS Trout Creek Mineral 9000 37.68 107.05 A Alnus incana-Salix drummondiana 95RG15 USFS Alamosa River Conejos 8650 37.38 106.35 A Alnus incana-Mixed Salix species 95RG17 USFS South Fork Cat Creek Rio Grande 8920 37.40 106.32 A Juncus balticus var. montanus 95RG18 USFS South Fork Cat Creek Rio Grande 8920 37.40 106.32 A Unclassified: Glyceria spp. Alliance 95RG22 USFS W. Fork Willow Creek (Del Norte) Rio Grande 9500 37.62 106.60 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 36 95RG39 USFS Big Hollow-Headwaters Rio Grande 11800 37.46 106.57 A Carex aquatilis 95RG42 USFS Beaver Creek Rio Grande 8380 37.74 106.68 A Alnus incana-Cornus sericea 95RG45 USFS North Fork Flume on the Conejos Conejos 10750 37.29 106.64 A Salix planifolia/Caltha leptosepala 95RG47 USFS No Name Confluence on El Rito Azul Conejos 10975 37.26 106.62 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 95RG49 USFS Middle Fork of the Conejos Conejos 10575 37.26 106.66 A Salix planifolia/Carex aquatilis 95RG50 USFS Saddle Creek Conejos 11800 37.30 106.56 A Caltha leptosepala 95RG51 USFS Saddle Creek Conejos 11800 37.30 106.56 A Salix planifolia/Caltha leptosepala 95RG53 USFS Treasure Creek Conejos 10740 37.37 106.65 A Salix planifolia/Mesic Forbs 95RG54 USFS South Fork of the Rio Grande above Big Meadow Reservoir Mineral 9430 37.53 106.82 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 95RG55 USFS South Fork of the Rio Grande above Big Meadow Reservoir Mineral 9430 37.53 106.82 A Abies lasiocarpa-Picea engelmannii/Ribes spp. 95RG56 USFS Hope Creek Mineral 9580 37.55 106.81 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 95RG58 USFS Nieve Canon Creek Mineral 10430 37.84 106.73 A Salix monticola/Carex aquatilis 95RG72 USFS Weminuche Creek Trib Hinsdale 9920 37.71 107.29 A Cardamine cordifolia-Mertensia ciliata- Senecio triangularis 95RG74 USFS Seep on Squaw Creek Hinsdale 10240 37.66 107.24 A Carex utriculata 95RG77 USFS Rio Grande Wetland East of Timber Hill Hinsdale 10010 37.76 107.08 A Carex utriculata 97BG02 USFS Dimick Gulch Saguache 8520 38.00 105.63 A Populus angustifolia-Juniperus scopulorum 97BG08 Private Cottonwood Creek near Cottonwood Town site Saguache 8400 37.88 105.63 A Pseudotsuga menziesii/Betula occidentalis 97BG09 USFS Saguache Creek @ Duckfoot Creek Saguache 9100 38.04 106.51 A Salix monticola/Calamagrostis canadensis 97BG14 USFS Blue Creek above Wagon Wheel Gap Mineral 10080 37.75 106.75 A Carex aquatilis 97BG15 BLM Nieland Creek Saguache 8840 38.25 105.88 A Populus tremuloides/Tall Mesic Forbs 97BG16 USFS Medano Lake Saguache 11520 37.86 105.49 A Salix brachycarpa/Mesic Forbs 97BG18 USFS Kelly Creek Saguache 9840 38.29 106.07 A Alnus incana/Mesic Graminoids 97BG20 USFS Slaughter House Creek Saguache 9680 38.29 106.17 A Populus tremuloides/Alnus incana 97EV13 Private Jacks Creek @ Cordova Homestead Saguache 8440 38.19 106.35 A Carex utriculata 97EV18 USFS Kerber Creek W of Bonanza Saguache 10520 38.33 106.18 A Abies lasiocarpa-Picea engelmannii/Mertensia ciliata 97EV20 USFS Piedrosa Creek @ Hot Creek Conejos 8480 37.25 106.25 A Pseudotsuga menziesii/Cornus sericea 97EV31 USFS Rito gato at Platoro Reservoir Conejos 10200 37.25 106.50 A Abies lasiocarpa-Picea engelmannii/Salix drummondiana 97EV32 STATE unnamed branch of La Jara Creek Conejos 9560 37.13 106.25 A Carex simulata fen 97EV35 USFS Mason Creek near Pearl Lakes Mineral 10760 37.80 107.28 A Salix planifolia/Carex aquatilis 97GK1 8 Private Rock Creek @ San Luis Creek Confluence Saguache 7900 38.25 105.88 A Carex simulata fen 97GK2 0 USFS Cottonwood Creek near Wilderness Boundary Saguache 8800 38.13 105.75 A Populus tremuloides/Betula occidentalis 97GK2 2 GSDNM Little Mendano Creek below Fire road Saguache 8600 37.75 105.50 A Alnus incana-Mixed Salix species 97GK2 3 USFS Medano lake Saguache 11520 37.75 105.38 A Cardamine cordifolia-Mertensia ciliata- Senecio triangularis 97GK2 4 USFS Sand Creek, 1.75 mi below Cleveland Gulch Saguache 8500 37.75 105.50 A Populus angustifolia/Salix drummondiana- Acer glabrum 97GK2 5 USFS Sand Creek, 1.75 mi below Cleveland Gulch Saguache 8500 37.75 105.50 A Populus angustifolia/Salix drummondiana- Acer glabrum 97GK2 6 USFS Sand Creek, 2 mi below Cleveland Gulch Saguache 8450 37.75 105.50 A Populus angustifolia/Salix drummondiana- Acer glabrum 97GK2 7 USFS/ Private Sand Creek, 2.25 mi below Cleveland Gulch Saguache 8240 37.75 105.50 A Abies concolor