Loading...
HomeMy WebLinkAboutHEARTHFIRE (HOFFMAN) - OVERALL DEVELOPMENT PLAN - 31-95 - SUBMITTAL DOCUMENTS - ROUND 1 - ENVIRONMENTAL REPORTAPPENDIX B U.S.G.S. Topographic Map. and Site Map 2. Photograph of Spiranthes diluvialis taken by Terry Geiselman, August 10, 1995. Photograph of Spiranthes diluvialis taken by Terry Geiselman, August 16, 1995. Photographs of Spiranthes diluvialis located in northwest Fort Collins. The site is a wet meadow approximately 1/2 mile south of the western end of Michaud Road adjacent to the Pleasant Valley and Lake Canal. Known site verified by Stephen W. Johnson, Spiranthes expert with Riverside Technology, inc. IIA.95 A 4ftiewe APPENDIX A Spiranthes diluvialis Documentary Photographs 6.0 LIST OF PREPARERS Riverside Technology, inc. 2821 Remington Street Fort Collins, Colorado 80525 (970)223-2944 - FAX (970)223-2955 Stephen W. Johnson, Spiranthes diluvialis Surveyor/Water Quality Hydrologist Terry Geiselman, Spiranthes diluvialis Surveyor/Geologist 5.4.5 Soils According to the Soil Survey of Lorimer County Area, Colorado (USDA 1980), the soils at the Hoffman site are characterized as follows. Kim loam, 3 to 5 percent slopes: This gently sloping soil is on uplands and fans. It consists of deep, well drained soils that formed in mixed alluvium. Permeability is moderate, and the available water capacity is high. Included with this soil in mapping are small areas of soils that are more sloping or less sloping and small areas of soils that have a surface layer of clay loam. A water table is within the root zone during the growing season in a few small areas. Also included are a few small areas of Fort Collins, Stoneham, and Thedalund soils. Runoff is medium, and the hazard of erosion is moderate. These soils are used mainly for irrigated and dry -farmed crops and for pasture and native grasses. Tassel sandy loam, 3 to 25 percent slopes: This gently sloping to moderately steep soil is on uplands. It consists of shallow, well drained soils that formed in material weathered from sandstone. These soils are on uplands and are underlain by soft sandstone at a depth of 10 to 20 inches. Permeability is moderately rapid, and the available water capacity is low. Included with this soil in mapping are some small areas of soils that have sandstone fragments on the surface and outcrops of sandstone. Also included are small areas of Nelson soils. Runoff is medium to rapid, and the hazard of erosion is severe. These soils are used mainly for native grasses. Fort Collins loam, I to 3 percent slopes: This nearly level soil is on terraces and fans. It consists of deep, well drained soils that formed in alluvium. Permeability is moderate, and the available water capacity is high. Included with this soil in mapping are a few small areas of soils that are more sloping or less sloping. Also included are some small areas of Stoneham and Kim soils and a few small areas of soils that have a gravelly layer below a depth of 40 inches. These soils are used for irrigated and dry -farmed crops and pasture. Runoff is slow, and the hazards of wind and water erosion are slight to moderate. When the landform is a swale, the Kim loam and Tassel sandy loam are considered hydric, according to the Larimer County Area, Colorado, Comprehensive Hydric Soils List (SCS 1993). 5.4.6 Hydrology The wetland areas at the site appear to be primarily the result of a shallow water table and ground water discharge. No distinct stream or drainage channels are evident. The cattail marsh is a swale in the topography that extends below the existing water table. Ground water seeps along the south - facing hillside (near the northwest shoreline of Richards Lake) are the main water sources for the wet meadow areas. The direction of ground water movement appears to follow the slope of the topography (to the south) toward Richards Lake. 0&95A340het 6 5.4.1 Overstory and Understory Vegetation The Hoffman site is characterized by sparse woody overstory consisting of riparian trees such as the Russian olive (Elaeagnus angustifolia ) and cottonwood (Populus spp.) growing near ponded water. It should be emphasized, however, that this overstory comprises less than 1% of the total basal area of the site. The understory at the site consists of upland and wetland vegetation. Upland vegetation includes western wheatgrass (Agropyron smithii), smooth brome (Bromus inermis), and invader forbs, such as Tarnsymustard (Descurainia pinnata). Wetland vegetation included cattails (Typha latifolia), rushes (Juncus articus), and inland saltgrass (Distichlis spicata). The Hoffman site has some disturbed areas, including a prairie dog town and an oil well pump site. There are also dirt trails and roads, some of which can accommodate motorized vehicles. These areas are in upland sites and are dominated by forbs and upland grasses. 5.4.2 Plant Community and Description The vegetation at the site falls into two vegetation communities: an upland vegetation zone and a wetland vegetation zone. The vegetation in each of these zones is described above under "Overstory and Understory Vegetation." 5.4.3 Ecological Condition/Management History The majority of the Hoffman survey area consists of an upland prairie. The site contains naturally occurring topographic low areas or swales that have developed into wet meadows and a cattail marsh. No distinct stream channel goes through the site; hydrology for the site is mainly ground- water -based. The cattail marsh appears to have been excavated at some time in the past to allow for ponding of open water. The presence of old pumps and irrigation pipes indicates that the water was possibly used for irrigation or watering livestock. A ditch with an old headgate had been constructed between the cattail marsh and a pond located to the north of the site. In addition, there is another ditch between the cattail marsh and Richards Lake. No evidence of recent flow exists in either ditch. - Horses were observed at the site grazing in both the upland and wetlands areas. The site also supports a dispersed prairie dog colony. Areas where the colony is more concentrated are extensively grazed by the prairie dogs. 5.4.4 Geomorphology The site slopes gently downward to the south, with the elevation ranging from approximately 5,075 to 5,125 feet amsl. Sandstone outcrops occur near the north side of Richards Lake. This area has a steeper gradient and appears to be a ground water discharge zone which supports a wet meadow area. The cattail marsh is a swale in the topography that extends below the existing water table. There is no evidence of landslide or other movement of the land. The majority of the site is vegetated. 0$95A340 eo 5 Colorado (USDA 1980), the soils at the Hoffman site are characterized as silty clay or loam and are generally well drained. Soils preferred by S. diluvialis may be gleyed or mottled but are not generally highly anaerobic. The species can occur in some disturbed sites (such as old gravel mines that have been developed into wetlands, and along well -traveled footpaths built on old berms) and also occurs in grazed pastures with introduced pasture grasses. Vegetation with which S. diluvialis can be found includes grasses, sedges and rushes, shrubs, and riparian trees such as Salix (willow). S. diluvialis rarely occurs in deeply shaded sites and prefers partially shaded open glades or pastures and glades in full sunlight. Species in the Front Range with which S. diluvialis is commonly associated, as well as species with which S. diluvialis is not usually found, are as follows: VEGETATION WITH WHICH VEGETATION WITH WHICH S. DILUVIALIS IS USUALLY FOUND S. DILUVIALIS IS NOT USUALLY FOUND • Horsetail (Equisetum spp.) • Milkweed (Asclepias incarnata) • Verbena (Verbena hastata) • Agalinis (Agalinis tenuifolia) • Lobelia (Lobelia siphilitica) • Blue-eyed grass (Sisyrinchium spp.) • Triglochin (Triglochin spp.) • Carpet bentgrass (Agrostis stolonifera) • Reedgrass (Calamagrostis spp.) • Goldenrod (Solidago spp.) • Reed canary grass (Phalaris arundinacea) • Tamarisk or salt -cedar (Tamariix ramosissima) • Greasewood (Sarcobatus vermiculatus) • Teasel (Dipsacus sylvestris) • Common reed (Phragmites australis) Of the vegetation in the above list, only Tamarisk (Tamarix ramosissima was present on the site. Tamarisk is not usually associated with S. diluvialis. 5.3 Survey Area The site was surveyed on August 10, 1995, by Stephen Johnson and Terry Geiselman of RTi. The boundaries of the site had previously been determined during a jurisdictional wetland survey. The wetland survey was conducted by RTi in June, 1995 and documented in a report entitled "Jurisdictional Wetlands Delineation Survey for the Hoffman P.U.D. Site, Fort Collins, Colorado." The boundaries of the site were determined using the U.S.G.S. topographic map for Fort Collins, City of Fort Collins plats, and a map provided by Jim Sell Design. After the boundaries were defined, the site was transversed with the two surveyors (Mr. Johnson and Mr. Geiselman) spaced 10 to 50 feet apart (depending on the observed site habitat and the related likelihood of S. diluvialis occurring). If, based on observed vegetation and hydrology, a site seemed more conducive to supporting S. diluvialis habitat, it was traversed more slowly, with the space between the surveyors narrowing. If a site seemed more unconducive to supporting S. diluvialis habitat, i.e., contained a prairie dog town or upland vegetation, the space between the surveyors was increased, with the surveyors sometimes walking up to 50 feet apart. 5.4 Site Ecoloeical Features The site ecological features are described in the order suggested by the survey report outline in the USFWS "Interim Survey Requirements for Spiranthes diluvialis." 0a93A34&UN 4 5.0 ECOLOGICAL AND SITE FEATURES The Hoffman site comprises 84.18 acres. The site was systematically surveyed on August 10, 1995 for occurrences of S. diluvialis. A survey methodology, developed to ensure that the survey was adapted to the site, involved the following steps: (1) Evaluate whether a survey is needed. (2) Establish orchid habitat survey criteria using current information. (3) Locate the survey boundaries in the field. (4) Conduct a field survey and characterize the site ecological features. The following sections provide details on the above -described steps. 5.1 Evaluate Whether a Survey is Needed According to the U.S. Fish and Wildlife Service (USFWS) document entitled "Interim Survey Requirements for Spiranthes diluvialis' (USFWS 1992), surveys are required for appropriate sites below 6,500 feet elevation in the following areas in Colorado: (1) Boulder and Jefferson Counties (2) The South Platte River 100-year floodplain and perennial tributaries from the Front Range as far east as Brush, Morgan County (3) The Fountain Creek 100-year floodplain and perennial tributaries from the Front Range to the southern boundary of El Paso County (4) The Yampa River 100-year floodplain and its perennial tributaries from Steamboat Springs west to the Utah border None of these requirements applies to the Hoffman site. The site is in Latimer County and is not in 100-year floodplains or along any perennial tributaries. However, the 1993 discovery of a S. diluvialis population in Northwest Fort Collins demonstrates that the orchids may exist in areas not defined in the USFWS "Interim Survey Requirements for Spiranthes diluvialis' (USFWS 1992). For this reason, Mr. Robert L. Wilkinson, Senior Environmental Planner for the City of Fort Collins Natural Resources Department, requires that a survey be conducted. The majority of the Hoffman survey area consists of an upland prairie. The general slope and drainage pattern of the site is from north to south (0-3%). The site contains naturally occurring topographic low areas or swales that have developed into wet meadows and a cattail marsh. No distinct stream channel goes through the site; hydrology for the site is mainly ground -water -based. The cattail marsh appears to have been excavated at some time in the past to allow for ponding of open water. The presence of old pumps and irrigation pipes indicates that the water was possibly used for irrigation or livestock watering. 5.2 Spiranthes diluvialis Habitat Criteria The USFWS "Interim Survey Requirements for Spiranthes diluvialis" (USFWS 1992) provides information on the habitat in which this orchid is found. According to the USFWS information, S. diluvialis is usually associated with alluvial deposits of silty, sandy, gravelly, or cobbly soil and may occasionally also occur in highly organic soils or peat. S. diluvialis appears to prefer well -drained soils with fairly high moisture content. According to the Soil Survey of Larimer County Area, 08.95ANatrn 3 since 1979. Over the past three years, Mr. Johnson has conducted wetland delineation studies in southeastern Wyoming, southern California, and the front range of Colorado. During August of 1993, Mr. Johnson trained with a S. diluvialis expert, Ms. Tamara Naumann of the City of Boulder Open Space Department, to become acquainted with the appearance and known locations of S. diluvialis. Mr. Johnson became familiar with the orchid in the Fort Collins area by assisting Ellen Wheeling in the orchid site on August 12, 1994. Mr. Geiselman is a Registered Geologist who is currently training under Mr. Johnson on several jurisdictional wetlands delineation projects and endangered species surveys. He has prepared the technical reports documenting the results of these activities. As part of his training, Mr. Geiselman has participated in jurisdictional wetlands surveys in Colorado and Wyoming and has prepared final documentation on the results of several surveys. Mr. Geiselman's qualifications include a B.S. in Geology, studies in hydrogeology and environmental science, and over 5 years of water resources related work. He has also participated in sensitive vegetation species and endangered animal surveys in California. Surveys for sensitive vegetation species included: 1) Shaggy -haired lupin (Cupinus spectarbillis) and 2) Mariposa clarkia (Clarkia biloba). The California endangered animal survey was conducted for the Limestone Salamander (Hydromantes brunnus). On August 10, 1995 Mr. Geiselman trained with Mr. Johnson to become acquainted with the appearance and known locations of S. diluvialis, since it was flowering at that time in the Fort Collins wet meadow. Mr. Johnson shared his expertise on the ecology, likely occurrences, and flowering of this federally threatened plant species. Three individuals of S. diluvialis were identified. Another visit to the Fort Collins site was made by Mr. Geiselman on August 16, 1995. No additional S. diluvialis plants were discovered. Photographs of S. diluvialis taken by Mr. Geiselman are presented in Appendix A. 3.0 PROJECT DESCRIPTION 3.1 Proposed Impact to Site The study site consists of a proposed filing called the Hoffman P.U.D. site (referred to hereafter as the Hoffman site). The Hoffman site is currently slated for proposed real estate development; if the site is developed, it will contain multi -family, single family, and patio/townhome residential developments. 3.2 Proiect Location A map of the Hoffman site is provided in Appendix B. The Hoffman site comprises 84.18 acres and is located in northwest Quarter of Section 30, Township 8 North, Range 68 West, City of Fort Collins, County of Larimer, State of Colorado. 4.0 DATES SURVEY WAS CONDUCTED The S. diluvialis survey for the Hoffman site was conducted on August 10, 1995, which corresponds to a time period when S. diluvialis was documented to be blooming in northwest Fort Collins (see Appendix A). 08.95A3+a*ev 2 1.0 INTRODUCTION This report discusses the results of a survey to determine the presence or absence of the federally threatened plant species Ute ladies' -tresses orchid (Spiranthes diluvialis) at the Hoffman P.U.D. Site in Fort Collins, Colorado. No occurrences of Spiranthes diluvialis were found. According to the USFWS "Interim Survey Requirements for Spiranthes diluvialis," (November 1992) the Fort Collins, Colorado, site discussed in this report does not need to be surveyed for Spiranthes diluvialis. However, a survey was conducted based on the following: 1) Mr. Robert L. Wilkinson, Senior Environmental Planner for the City of Fort Collins, indicated that a Spiranthes diluvialis survey is required by the City of Fort Collins Natural Resources Department and 2) Spiranthes diluvialis's were identified in 1993, growing within the city limits of Fort Collins. The survey was conducted on August 10, 1995. A discussion of the Spiranthes diluvialis's population found in Fort Collins is presented below. Information is taken from the Report entitled "Spiranthes Dlluvialis Survey Report" prepared by Ellen C. Wheeling and Shaunda Kennedy, 1993, for the Fort Collins Department of Natural Resources. Thirty one Larimer County wetland sites were surveyed for Spiranthes diluvialis, Ute ladies' -tresses orchid, between July 15 and September 6, 1993 by Ellen C. Wheeling and Shaunda Kennedy of the Fort Collins Department of Natural Resources. One orchid population consisting of 13 individuals was located on August 30, 1993. The orchids were growing in a wet graminoid meadow located approximately 1/2 mile south of the western end of Michaud Lane and adjacent to Pleasant Valley and Lake Canal. The wet meadow is part of a large pasture dominated by a mixture of native and introduced grasses. It is used by Colorado State University for summer range. The wet meadow occupies a depression at the base of the eastern bank of Pleasant Valley and Lake Canal. It appears to be supported primarily by groundwater and seepage from the canal. The Pleasant Valley and Lake Canal is an irrigation ditch which contains water year round. Flow in the canal is diverted from the Cache LaPoudre River. Flows average from 11,000 to 12,000 acre-feet per year. Soils are apparently saturated throughout most of the growing season. Meadow grasses are relatively tall (2 to 3 feet) and very dense. They provide nearly 100% aerial cover. Ground cover (litter) is dense and up to two inches thick in some places. The wet meadow in Fort Collins appears to be atypical S. diluvialis habitat. Grasses provide much more cover than is found at other known Colorado orchid locations. They also appear to be taller and more dense than those at the Boulder, Wheat Ridge, and Clear Creek sites. The information provided above, together with the USFWS guideline, was combined in the survey documented in this report. 2.0 NAME AND QUALIFICATIONS OF SURVEYOR The Ute ladies' -tresses orchid (Spiranthes diluvialis) survey was conducted by Stephen W. Johnson and Tent' Geiselman, both of Riverside Technology, inc. (RTi). Mr. Johnson has botanical expertise and training through his B.S. in biology from the University of Arizona and his M.S. in plant ecology from Colorado State University. He has conducted plant surveys in the Colorado/Wyoming area oxvs.v"e.0 1 TABLE OF CONTENTS Page 1.0 INTRODUCTION 1 2.0 NAME AND QUALIFICATIONS OF SURVEYOR 1 3.0 PROJECT DESCRIPTION 2 3.1 Proposed Impact to Site 2 3.2 Project Location 2 4.0 DATES SURVEY WAS CONDUCTED 2 5.0 ECOLOGICAL AND SITE FEATURES 3 5.1 Evaluate Whether a Survey is Needed 3 5.2 Spiranthes diluvialis Habitat Criteria 3 5.3 Survey Area 4 5.4 Site Ecological Features 4 5.4.1 Overstory and Understory Vegetation 5 5.4.2 Plant Community and Description 5 5.4.3 Ecological Condition/Management History 5 5.4.4 Geomorphology 5 5.4.5 Soils 6 5.4.6 Hydrology 6 6.0 LIST OF PREPARERS 7 APPENDICES APPENDIX A Spiranthes diluvialis Documentary Photographs APPENDIX B U.S.G.S. Topographic Map and Site Map 08.95A34a'wc Ute Ladies' -Tresses Orchid (Spiranthes diluvalis) Survey for the Hoffman P.U.D. Site Fort Collins, Colorado prepared by Riverside Technology, inc. 2821 Remington Street Fort Collins, Colorado prepared for Bill Yunker Richards Lake Development Co. 5319 Paradise Lane Fort Collins, Colorado August 1995 0&95 A34Wcowr