Affected Environment & Environmental Consequences – T, E & S Plants 3.8 THREATENED, ENDANGERED AND SENSITIVE PLANT SPECIES 3.8.1 SCOPE OF THE ANALYSIS AND ANALYSIS METHODS An evaluation of threatened, endangered, and sensitive list plant species for the Trapper Bunkhouse Project Area was conducted. There is one federally listed threatened plant species in the state of Montana that occurs on National Forest Lands. Water howellia (Howellia aquatilis) was listed by the U.S. Fish and Wildlife Service on July 14, 1994. This species is not known to occur on the Bitterroot NF. There are no known endangered plant species on the Bitterroot NF, and none suspected to occur. The Northern Region Sensitive Plant Species List (USDA Forest Service 2004a) identifies a number of plants for each National Forest for which population viability is a concern. This list includes 33 plant species on the Bitterroot NF. A review of the Montana Natural Heritage Program (MNHP) database and past Bitterroot National Forest plant surveys for known locations of sensitive plants within the project are was performed. Surveys had been conducted by Forest botanists and biological technicians as part of the Spoon-McCoy Salvage and Underburn, Huck-Trap Environmental Assessment (1994) and the Fern Creek Environmental Assessment (1995). Field surveys in the Trapper Bunkhouse Project Area in locations not previously surveyed were conducted in the summers of 2005 and 2006 by Bitterroot NF field botanists for the following species. Follow- up surveys of additional units, as well as proposed temporary roads and helicopter landings, were surveyed during the summer of 2007. The Project Area was also assessed for inclusion of habitat that might be suitable for other sensitive plant species by reviewing timber stand data and aerial photo interpretation. A list of sensitive plant species either known to occur in or near the Project Area or that have the potential to occur in the Trapper Bunkhouse Project Area is displayed in Table 3.8-1. Table 3.8- 1: Sensitive Plants Common Name Scientific Name Tapertip onion Allium acuminatum Dwarf onions Allium parvum Sandweed Athysanus pusillus Rocky Mountain paintbrush Castilleja covilleana Yellow lady's-slipper Cypripedium parviflorum Giant helleborine Epipactis gigantea Western boneset Eupatorium occidentale Spiny greenbush Glossopetalon nevadense Puzzling halimolobos Halimolobos perplexa Idaho goldenweed Haplopappus aberrans Western pearl-flower Heterocodon rariflorum Scalepod Idahoa scapigera Dwarf purple monkeyflower Mimulus nanus Turkey-peas Orogenia fusiformis Lemhi penstemon Penstemon lemhiensis Payette penstemon Penstemon payettensis Woolly-head clover Trifolium eriocephalum Hollyleaf clover Trifolium gymnocarpon California false hellebore Veratrum californicum 3.8 - 2 Trapper Bunkhouse Land Stewardship Project Final EIS Affected Environment & Environmental Consequences – T, E & S Plants Three sensitive plant species were found within the Project Area: dwarf onion (Allium parvum), Lemhi penstemon (Penstemon lemhiensis) and sandweed (Athysanus pusillus). In addition, four species of interest on the Forest were found: candystick (Allotropa virgata), Columbia lewisia (Lewisia columbiana), Yerba buena (Satureja douglasii) and bitterroot (Lewisia rediviva). An evaluation of the possible effects from management activities was conducted for these species and their habitat. The effects of proposed management activities on sensitive plant species were assessed by evaluating impacts to population numbers, habitat and population viability of these species at several geographic scales: 1) global range; 2) statewide range; 3) on the Bitterroot National Forest and; 4) within the Project Area. Information on individual species, their habitat, distribution and known occurrences within the state come from the Montana Natural Heritage Program. There is little, if any, information on the distribution of these species historically so cumulative effects are based on knowledge about habitat and similar species within the genus. More current information comes from monitoring sensitive plant populations for effects of management activities and wildfires. 3.8.2 REGULATORY FRAMEWORK The Endangered Species Act requires that the Forest Service conserve endangered and threatened species. The National Forest Management Act and Forest Service policy direct that National Forests be managed to maintain populations of all existing native plant and animal species at or above minimum population levels. A minimum viable population consists of the number of individuals adequately distributed throughout their range necessary to perpetuate the existence of the species in natural, genetically stable, self-sustaining populations. Plant species for which population viability is a concern are identified by the Forest Service as sensitive species. This category may include federal candidates (plants being studied by the U.S. Fish and Wildlife Service for proposed listing as threatened or endangered status), or plant species proposed for listing as threatened or endangered in the Federal Register (MNHP 2006). Sensitive species can also be species that are considered rare within the state of Montana or otherwise potentially of concern as determined by the Montana Natural Heritage Program. The Forest Service Manual requires that activities conducted on National Forests be reviewed for possible impacts on endangered, threatened, or sensitive species (FSM 2670). The Biological Evaluation (BE) consists of the written narrative below and the signed table located at the end of Section 3.8.4.D. It is also located in the Project File (PF-SENS-062). 3.8.3 AFFECTED ENVIRONMENT The Tin Cup Fire, which occurred in August 2007, burned into the northern part of the Trapper-Bunkhouse Project Area. The fire burned into unit 26 (a commercial thinning unit proposed in Alternative 2 in the DEIS). Burn severity was light-to-moderate, with some higher severity patches in the southeast corner. A. Sensitive Plant Species Lemhi Penstemon (Penstemon lemhiensis) Lemhi penstemon is found on open, east to southwest facing slopes in grasslands and open ponderosa pine or Douglas-fir and can be associated with big sagebrush (Artemisia tridentata var. vasseyana) and bitterbrush (Purshia tridentata). It is a regional endemic, found only in southwestern Montana and adjacent Lemhi County, Idaho. Elevations range from 3200-8100 feet (Elzinga 1997). There are 90 known occurrences in Montana, 26 of which are located on the Bitterroot National Forest, two of these within the Trapper Bunkhouse Project Area. Many populations are small, only six on the Bitterroot Forest have over 100 individuals. It is theorized that Lemhi penstemon may be a recently evolved hybrid species, which is why it can occupy a variety of habitats. Spotted knapweed (Centaurea biebertsteinii {C. maculosa}) is a threat on most of the Lemhi Trapper Bunkhouse Land Stewardship Project Final EIS 3.8 - 3 Affected Environment & Environmental Consequences – T, E & S Plants penstemon sites on the Bitterroot Forest, particularly in areas that burned, creating a concern for management of the species, since fire appears to be critical to its survival. Monitoring of three Lemhi penstemon populations in Beaverhead County over a six-year period has demonstrated that population trends are closely tied to the existence of a seed bank (Heidel and Shelly 2001). Seeds appear to remain viable for at least six years and germination occurs during years of high moisture and disturbances such as fire. This determination appears to be in accord with recent monitoring on the Bitterroot NF. Botanists here have noted an increase in Lemhi penstemon on a monitoring site during the wet summers of 1993 and 1995, and another population that burned in the 2000 fires had hundreds of seedlings germinating for up to three years after the fire (USDA Forest Service 2003b). The Montana Natural Heritage Program ranks Lemhi penstemon as G3/S2, which means that the species is potentially at risk globally and at risk in Montana due to limited occurrences and vulnerability to extirpation in the state. A conservation strategy for Lemhi penstemon was prepared in 1997 and lists threats to the species from grazing, mining, road maintenance and reconstruction, timber harvest, noxious weed encroachment, herbicide application, fire suppression, interaction of weed infestation and prescribed fire, and small population sizes (Elzinga 1997). There are two populations of Lemhi penstemon in the Trapper Bunkhouse Project Area, one of these is in the Little Trapper Creek drainage, outside any unit boundaries; and the other is located in the Trapper Creek drainage with one plant within unit 15. The Little Trapper Creek population was originally found in 1995 and has been visually monitored every few years since then. There have been up to 43 individuals in the population, but only one basal rosette was located in 2005. The Trapper Creek population was discovered during surveys the summer of 2005 and consisted of only three plants. Dwarf Onion (Allium parvum) Dwarf onion is associated with grasslands, sagebrush and large open areas in ponderosa pine (Pinus ponderosa), usually in exposed sites with sandy or gravelly soil. Bitterroots (Lewisia rediviva) are found in similar habitat and the two species may be seen growing together. The greatest threat to dwarf onion plants and habitat is spotted knapweed encroachment, along with other weeds - like cheatgrass and sulfur cinquefoil - that are often
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