Exhibit_01_SCNF_Rare_Plant_Species.pdf

Exhibit 1: Salmon-Challis National Forest Rare Plant Species List

Rare Plant Species Presence and Distribution on SCNF

For ease of analysis, the project area has been divided into five zones (Map 1). These zones make it easier to display and understand figures and numbers that are shown in Table 1. These five zones are based, overall, on watershed and administrative boundaries.

MAP 1. Plant Management Zones on the Salmon-Challis National Forest

2019 – 2023 IDIQ SCNF Invasive Species/Rare Plants Vegetation Management Services

The Natural Resource Information System is the national FS database for storing and using natural resource data. NRIS is composed of modules for different natural resources (e.g. water, wildlife, or vegetation). The data is housed by the USDA National Information Technology Center on servers in Kansas City, MO. Invasive plant inventory and treatment data and Sensitive plant population data is stored nationally in this database. National Forests enter and query invasive plant inventory and treatment data and Sensitive plant population occurrences through the FS Natural Resource Manager system, which is responsible for maintaining NRIS.

There are no ESA-listed Threatened or Endangered plant species on SCNF. There is one candidate species, whitebark pine, proposed for listing that would include SCNF if eventually listed. There are 21 Sensitive plant species identified by the Regional Forester for SCNF (including whitebark pine). Some of these species have highly specific habitat requirements and only occur in a few places. Other species have broad distributions and occur in a variety of cover types.

Table 1 displays the known presence of the Candidate and Sensitive plant species in the project area by invasive plant management zone, based on data queries of the USDA FS SCNF NRIS database (2012). Of the five invasive plant management zones, the Pahsimeroi-Lost zone hosts the highest number of SCNF Sensitive plant species, with known populations of six species. The Lemhi, Salmon and Upper Salmon zones each contain known populations of five SCNF Sensitive plant species. The North zone contains the fewest, with known populations of three SCNF Sensitive plant species.

Table 1. Region 4 Sensitive Plant Species Occurrence by Invasive Plant Management Zone

Scientific Name Common Name Habitat Association

Upper Salmon

Zone

Pahsimeroi Lost Zone

Salmon Zone

North Zone

Lemhi Zone

Agoseris lackschewitzii

Pink agoseris

Wet meadows with soil saturated through the growing season

Not Known to

Occur

Not Known to Occur X

Not Known to Occur

X

Astragalus amnis-amissi

Lost River milkvetch

Cracks in ledges of similar sites on near vertical limestone cliffs, and in talus at base of cliffs;

mostly in moist shaded areas

Not Known to

Occur X

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Astragalus aquilonius

Lemhi milkvetch

Unstable substrates such as gullies, washes and gravel banks often on southerly aspects

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Astragalus diversifolius

Meadow milkvetch

Moist, alkaline soil in meadows and sagebrush valleys near springs and spring-fed streams.

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Astragalus vexilliflexus var.

nubilus

White Cloud milkvetch

Dry open ridges in White Cloud Range X Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Scientific Name Common Name Habitat Association

Upper Salmon

Zone

Pahsimeroi Lost Zone

Salmon Zone

North Zone

Lemhi Zone

Carex incurviformis var.

incurviformis

Seaside sedge

Alpine and subalpine moist tundra and wet rock ledges. Elevation 10,000 to 12,200 feet

Not Known to

Occur X

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Collomia debilis var. camporum

Flexible alpine collomia

Talus slopes at high elevations

Not Known to

Occur

Not Known to Occur X X

Not Known to Occur

Cymopterus douglassii

Douglas’ biscuitroot

Alpine and subalpine areas on open slopes, ridges, and summits in calcareous or dolomitic substrates

Not Known to

Occur X

Not Known to

Occur

Not Known to Occur

X

Draba densifolia apiculata

Rockcress draba

Moist, gravelly alpine meadows and talus slopes, often on limestone-derived soils

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Draba trichocarpa

Stanley’s whitlow-grass

Steep slopes on granitic parent material

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Eriogonum capistratum var.

welshii

Welsh buckwheat

Rocky volcanic slopes, gravelly clay or sedimentary barren flats with minimal vegetation consisting of scattered sagebrush and grasses

Not Known to

Occur X

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Eriogonum meledonum

Guardian buckwheat

Unstable scree slopes on granitic parent materials

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Lewisia sacajaweana

Sacajawea’s bitterroot

Open ridgelines in montane and subalpine areas at high elevation on coarse-textured granitic and volcanic soils

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Oxytropis besseyi var.

salmonensis

Challis crazyweed

Sagebrush and salt desert shrub in sandy washes or open slopes of rocky volcanic soil

X Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Penstemon lemhiensis

Lemhi penstemon

Grassland and open ponderosa pine forests between 6,300 and 7,200 feet

Not Known to

Occur

Not Known to Occur X X X

Scientific Name Common Name Habitat Association

Upper Salmon

Zone

Pahsimeroi Lost Zone

Salmon Zone

North Zone

Lemhi Zone

Pinus albicaulis Whitebark Pine

Harsh, high elevation sites across the northern Rocky Mountains, often on decomposed granitic soils. High and rapid mortality rate due to introduced blister rust.

X X X X X

Physaria didymocarpa var. lyrata

Salmon Twin Bladderpod

Rocky, sparsely vegetated, south slopes.

Bare ground and rock coverage (1-3 inches rock)

Not Known to

Occur

Not Known to Occur X

Not Known to Occur

X

Poa abbreviata ssp. marshii

Marsh's Bluegrass

Alpine fell-fields Not Known to

Occur X

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Thelypodium repandum

Wavy-leaf Thelypody

Moderate to steep, unstable, generally southerly facing slopes of rocky, gravelly to cindery substrate derived from Challis volcanic and metamorphic rock.

Associated vegetation is sparse (5 to 20% cover), and bare ground coverage is high

X Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Noccaea fendleri ssp. idahoensis

Idaho pennycress

Steep slopes on sandy and gravelly soil on sagebrush flats

X Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Xanthoparmelia idahoensis

Idaho range lichen

Calcareous badlands on gentle to moderate slopes that are barren to sparsely vegetated with shrub-steppe plants

Not Known to

Occur

Not Known to Occur

Not Known to

Occur

Not Known to Occur

Not Known to Occur

Determining species or habitats that may be rare or declining is an important factor in maintaining biodiversity. To assist with these determinations, researchers and land managers use a common set of conservation status rankings. These standardized rankings indicate how likely a species is to be extirpated from all or part of its range and indicate habitat quantity and quality. Each of the 21 plant species designated as Sensitive for SCNF are assigned a conservation status rank, which is stated and defined in the section below. For more information about conservation status ranking, NatureServe provides more detailed information at NatureServe, an online network that summarizes data from various data centers across the U.S. to provide scientific information about the status and distribution of species of conservation concern.

Of the 21 plant species designated as Sensitive for SCNF, only one, whitebark pine, occurs in all five zones. The next species with the broadest distribution is Lemhi penstemon, which occurs widely over the North, Lemhi and Salmon zones (USDA FS SCNF NRIS database 2012). Four SCNF Sensitive plant species occur in only two of the five zones while eight species are known to occur only in one zone (See Table 1). Seven plant species listed as Sensitive for SCNF have not been located in SCNF in surveys to date. The following section summarizes the biological requirements, population status and trend and occurrence in the project area for each of the 21 SCNF Sensitive plant species (NatureServe 2013).

Agoseris lackschewitzii (Pink Agoseris) Biological Requirements: This species occurs in wet montane meadows in soils that are saturated throughout the growing season at mid-montane to subalpine elevations (Matthews 1989). Overstory trees, when present, are usually subalpine fir (Abies lasiocarpa), Engelmann spruce (Picea engelmannii), whitebark pine (Pinus albicaulis), and Douglas-fir (Pseudotsuga menziezii). Associated species include tufted hairgrass (Deschampsia cespitosa), bistort (Polygonum bistorta), elephant’s-head lousewort (Pedicularis grounlandica), and arrowleaf groundsel (Senecio triangularis).

Trend and Potential Occurrence: Pink agoseris has a global ranking of G4; apparently secure, uncommon but not rare, some cause for long–term concern due to declines or other factors, and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). It is known to occur in Idaho, Washington, Wyoming and Montana. In Idaho, it has been found in Fremont and Lemhi Counties. Pink agoseris is known to occur in the project area in the Lemhi and Salmon Zones.

Astragalus amnis-amissi (Lost River Milkvetch) Biological Requirements: Lost River milkvetch occurs on ledges and rock crevices of nearly vertical limestone cliffs and in talus at the base (Moseley 1989). It prefers moist, shaded microsites within these general habitats. This milkvetch blooms June to July. There are no known threats to habitat for this species in the project area (NatureServe 2013).

Trend and Potential Occurrence: Lost River milkvetch has a global ranking of G3 and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). This species is distributed on the eastern and western slopes of the southern half of the Lost River Range and the southern end of the Lemhi Range in Custer and Butte Counties. It occurs only in the Pahsimeroi-Lost zone.

Astragalus aquilonius (Lemhi Milkvetch) Biological Requirements: It is found on unstable substrates, steep banks, sandy washes, and gullies within the shrub-steppe zone. It occurs often on southerly aspects in gravelly and sandy to ashy and sometimes clayey soils (USDA FS 1989, NatureServe 2013). This species blooms May to June.

Trend and Potential Occurrence: The Lemhi milkvetch has a has a global ranking G3 and a state ranking of S3; vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

Lemhi milkvetch is endemic to east-central Idaho and occurs in Custer, Butte, and Lemhi Counties at lower elevations. Its main distribution is on lower slopes of the Salmon River from Ellis to Clayton and the East Fork Salmon River upstream to the vicinity of Herd Creek. Populations are also found on the southern end of the Lemhi Range, the Lemhi River valley near Lemhi, and in scattered locations in the Pahsimeroi and Lost River valleys (USDA Forest Service 1989). Thorough searches of suitable-appearing habitat in lower elevations of Forest Service land in the Lemhi Valley between Salmon and Leadore, Idaho, did not yield any detections of Lemhi milkvetch (Moseley 1989). Moseley attributed the absence of Lemhi milkvetch in suitable-appearing habitats on Forest Service land to a lack of the specific soil substrates required by the species. Based on this survey, Lemhi milkvetch does not occur within the project area.

Astragalus diversifolius (Meadow Milkvetch)

Biological Requirements: Meadow milkvetch occurs on moist alkaline, generally hummocky, meadows near springs and along small spring-fed streams (Moseley 1992c, Jankovsky-Jones 1999). This species flowers in June and July (NatureServe 2013). Threats to this species include livestock grazing and loss of habitat to agriculture (Jankovsky-Jones 1999, NatureServe 2013).

Trend and Potential Occurrence: Meadow milkvetch has a global ranking of G2 and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This species is endemic to central Idaho and northern Utah with one historical report for the Green River Basin in western Wyoming. In Idaho, it is distributed primarily in Custer and Lemhi counties, in the valleys of the Big Lost, Little Lost, Pahsimeroi, and Lemhi Rivers and in Birch Creek (Moseley 1992c). It is not known to occur in the project area, although there is apparently suitable habitat in the Lemhi and Pahsimeroi-Lost zones.

Astragalus vexilliflexus var. nubilus (White Cloud Milkvetch) Biological Requirements: This milkvetch is found on scree slopes and in sagebrush communities. This species blooms from August to September (USDA Forest Service 1989). Threats to this species include livestock grazing, noxious invasive plant infestations, road maintenance activities, OHV off-route use, and, to a lesser degree, hiking activities (NatureServe 2013).

Trend and Potential Occurrence: White Cloud milkvetch has a has a global ranking of G4; apparently secure, uncommon but not rare, some cause for long-term concern due to declines or other factors; an infraspecific taxon rank of T2; and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This species is found in Custer County in subalpine and alpine areas in the White Cloud Range (USDA Forest Service 1989). Mapped locations occur on portions of SCNF administered by the Sawtooth National Recreation Area. In the project area, it is known to occur only in the Upper Salmon zone.

Carex incurviformis var. incurviformis (Seaside Sedge) Biological Requirements: This sedge occurs in alpine and subalpine zones on moist tundra and wet rock ledges. It is a circumpolar species that is known from high elevation areas (10,000 to 12,000 feet) from Canada, south to Colorado and California (NatureServe 2013). Threats to this species have not been identified (NatureServe 2013).

Trend and Potential Occurrence: The seaside sedge has a global ranking of G5/G4 and an infra-specific taxon rank of T4/T5; a range rank that is used to indicate the range of uncertainty of the status of the species. The status is approximately equal between being secure, common, widespread and abundant and apparently secure, uncommon but not rare, some cause for long-term concern due to declines or other factors. The species is unranked, the state conservation status having not yet been assessed (NatureServe 2013). There is one mapped location of this species on SCNF within a roadless area in the Pahsimeroi-Lost zone.

Collomia debilis var. camporum (Flexible Alpine Collomia) Biological Requirements: The flexible alpine collomia inhabits stabilized talus slopes (Moseley 1992a).

Threats to this species have not been identified (NatureServe 2013).

Trend and Potential Occurrence: The flexible alpine collomia has a has a global ranking of G5 secure, common, widespread and abundant; an infraspecific taxon rank of T2; and a state ranking of S2;

imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This species occurs in the North Fork of the Salmon River drainage in Idaho and in adjacent Montana (Moseley 1992a). There are several known populations in the project area in North and Salmon zones.

Cymopterus douglassii (Douglas' Biscuitroot) Biological Requirements: Populations consist of thousands to tens of thousands of individuals (NatureServe 2013). It occurs in alpine and subalpine zones on open slopes, ridges, and summits with calcareous or dolomitic substrates and blooms from mid-June to August (USDA Forest Service 1989). In high mountain cirque terrain it is found on sites that are level, gravelly, and with evidence of frost heaving (Moseley 1992b). There are no known threats to this species (NatureServe 2013).

Trend and Potential Occurrence: The Douglas’ biscuitroot has a global ranking G3 and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This plant is known primarily from very high elevation sites (over 9,000 feet) in Custer County in the vicinity of Borah Peak in the Pahsimeroi-Lost zone. One population, also at high elevation, is known from Sheep Mountain in the Lemhi Range within the Lemhi zone.

Draba densifolia apiculata (Rockcress Draba) Biological Requirements: This species occurs in moist, gravelly alpine meadows and on granitic talus slopes or rock crevices. This species usually occurs on limestone-derived soils. It occurs at very high elevation sites in Wyoming, Utah, Montana, central Colorado, and Idaho (Ladyman 2004). Recreational use may impact some populations (NatureServe 2013).

Trend and Potential Occurrence: Rockcress draba has a global ranking of G3; vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation and a state ranking of S2;

imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). There are no mapped populations on SCNF, although there is an anecdotal report of rockcress draba well above treeline on Mount Borah (Earle and Earle 2012).

Draba trichocarpa (Stanley's Whitlow-grass) Biological Requirements: This species is found in sagebrush/Idaho fescue (Artemisia arbuscula ssp.

thermopola/Festuca idahoensis) habitat type variation with a mosaic that includes mountain big sagebrush (Moseley and Mancuso 1990). On a majority of sites, it was found growing with guardian buckwheat (see below). It occurs on granitic bedrock on steep rock outcrops and stable residual scree developed from the Idaho Batholith (Moseley and Mancuso 1993). Ground disturbance associated with cattle and elk grazing, off-route OHV use, noxious invasive plant infestations and herbicide treatment, road construction or maintenance and housing development pose threats to populations of this species (Moseley 1988, NatureServe 2013).

Trend and Potential Occurrence: Stanley’s whitlow-grass has a global ranking of G2 and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

Stanley's Whitlow-grass is a highly localized species endemic only to the Stanley Basin within two miles of the valley floor (Moseley 1988). All populations are restricted to granite outcroppings found to the north and south of the town of Stanley (Moseley 1988, Moseley and Mancuso 1990). Searches in apparently suitable habitat elsewhere in the Stanley Basin have not located any other populations (Moseley 1988). All populations occur on private land or within the Sawtooth National Recreation Area.

None occur in the project area in SCNF.

Eriogonum capistratum var. welshii (Welsh Buckwheat) Biological Requirements: Welsh buckwheat occupies dry, sparsely vegetated rocky volcanic slopes (Murphy 2002). It is often associated with scattered sagebrush and grasses, usually at elevations between 6,000 to 7,800 feet. The plant flowers in late June to early July. Threats to this species include livestock grazing, OHV use, and mining (Murphy 2002).

Trend and Potential Occurrence: The Welsh buckwheat has a global ranking of G4; apparently secure, uncommon but not rare, some cause for long-term concern due to declines or other factors; an infraspecific taxon rank of T2; and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation. The taxonomy of this species is questionable; resolution of this uncertainty may result in change from a species to a subspecies or hybrid, or the inclusion of this taxon in another taxon, with the resulting taxon having a lower-priority conservation priority (NatureServe 2013).

This species is endemic to east-central Idaho. It is known to occur in the valleys and foothills of the upper Big Lost, Little Lost, and Pahsimeroi rivers in Custer and adjacent potions of Lemhi and Butte counties. In the project area, it is known to occur only in the Pahsimeroi-Lost zone.

Eriogonum meledonum (Guardian Buckwheat) Biological Requirements: The guardian buckwheat occurs on unstable scree slopes on granitic parent materials (USDA Forest Service 1990). Invasive plant invasion and OHV use are identified threats to this species (NatureServe 2013).

Trend and Potential Occurrence: The guardian buckwheat has a global ranking of G2 and a state ranking of S2; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation. Guardian buckwheat is a highly localized species endemic only to the Stanley Basin (Moseley 1988).

It occurs in similar habitats as the Stanley whitlow grass, but extends further south in the Stanley Basin.

It is known from eight occurrences that are mostly located on the Sawtooth National Recreation Area (Mancuso 2001). Searches in apparently suitable habitat have not located any populations in SCNF (Moseley 1988).

Lewisia sacajaweana (Sacajawea’s Bitterroot) Biological Requirements: This species was separated from a closely related form in California in 2005 (Wilson et al 2005). It occurs on open ridgelines in montane and subalpine areas at high elevations on coarse-textured granitic and volcanic soils.

Trend and Potential Occurrence: Sacajawea’s bitterroot has a global ranking of G2 and a state ranking of S1; imperiled, at risk because of restricted range, few populations, rapidly declining numbers, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This is a newly described species apparently endemic to the mountains of central Idaho within 6-7 Idaho counties with approximately 30 occurrences identified. Populations of Lewisia sacajaweana were previously thought to be Lewisia kelloggii (Kellogg's lewisia), but were reclassified as a separate species based on technical characteristics (Wilson et al 2005). There are no known populations within the project area in SCNF, although a few sites formerly identified as Kellog’s lewisia are mapped in the Frank Church-River of No Return Wilderness to the west of the project area.

Oxytropis besseyi var. salmonensis (Challis Crazyweed) Biological Requirements: This species occurs in sagebrush and salt desert shrub habitats. It occurs in sandy washes and open slopes with rocky volcanic soils where it blooms June through July (USDA Forest Service 1990). Threats to this species have not been identified (NatureServe 2013).

Trend and Potential Occurrence: The Challis crazyweed has a has a global ranking of G5 secure, common, widespread and abundant; an infraspecific taxon rank of T3; and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013).

This species is endemic to Custer County. It is known to occur in the Big Lost, Pahsimeroi, and Upper Salmon watersheds (NatureServe 2013). Within the project area, it is known to occur only in the Upper Salmon zone.

Penstemon lemhiensis (Lemhi Penstemon) Biological Requirements: Lemhi penstemon’s bright sky-blue flowers appear from June to July. This penstemon is an early seral species that requires bare soil to become established. It appears to be dependent on small-scale disturbances and has adapted to man-made disturbed sites, such as road cuts and fills and responds favorably after fire (Elzinga 1997, Heidel and Shelly 2001). Populations from artificial habitats (such as road cuts) do not contribute appreciably to the overall viability of the species (Elzinga 2013). It occurs in a variety of habitats, including dry grasslands, three-tipped sage/Idaho fescue and big sagebrush/needle-and- thread communities, mountain big sagebrush/bluebunch wheatgrass, open conifer ponderosa pine or Douglas-fir/grass lands, and ecotones between forest and shrub-steppe.

It occurs at elevations from 3,200 to 8,100 feet (Moseley et al 1990a, Moseley 1992a). Threats to this species include road construction, road maintenance, mining, botanical collection, herbicide spraying,invasive plant invasion, and livestock grazing (Moseley et al 1990a, Elzinga 1997, Heidel and Shelly 2001, Stucki and Rodhouse 2009).

Trend and Potential Occurrence: NatureServe denotes Lemhi penstemon as a global ranking of G3 and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). This species is endemic to Lemhi County and adjacent counties in Montana (Moseley et al 1990a). Note that the conservation status ranking for this species is not very applicable to populations in SCNF. Lemhi penstemon is one of the two most common Sensitive plant species on SCNF, occurring widely distributed over the Salmon, North and Lemhi zones (USDA FS SCNF NRIS database 2012). Lemhi penstemon is usually present in plant communities at apparently low levels (Elzinga 1997, Stucki et al 2013). However, its abundance is cyclical and, in years with favorable conditions, Lemhi penstemon can be a visually dominant plant community component (Elzinga 1997, Stucki et al 2013). There are large populations in SCNF containing hundreds of plants (Schuldt 2013).

Pinus albicaulis (Whitebark Pine) Listing Status: In July 2011, the USFWS published a rule stating that the listing of whitebark pine as threatened or endangered was warranted, but precluded due to higher priority listing actions (USFWS 2011). Whitebark pine is currently a candidate species proposed for listing under the ESA. Whitebark pine is also listed by the Regional Forester as a Sensitive plant species for SCNF.

Biological Requirements: Whitebark pine is a long-lived, slow-growing stone pine. They occur in high elevation forests and at timberline distributed in coastal and Rocky Mountain ranges from the northern coastal mountains in British Columbia to the Sierra Nevada Mountains in California. Rocky Mountain populations range in elevation from approximately 5,900 to 10,500 feet. They are found on harsh, cold sites on rocky, poorly developed soils that lack fine material with snowy, wind-swept exposures.

Whitebark pines are found in association with subalpine fir (Abies lasiocarpa), lodgepole pine (Pinus contorta) and Engelmann spruce (Picea engelmannii). Whitebark pine is intolerant to moderately intolerant of shade (Arno and Hoff 1989).

On most sites, trees do not reach full cone production until 60 to 100 years of age. Cones remain closed, or indehiscent. Clark’s nutcrackers play an essential role be prying open the cones, collecting the seeds, and then caching the seeds, which subsequently germinate. Other rodents, such as red squirrels, chipmunks, and ground squirrels, also cache seeds. Other species, such as black and grizzly bears feed upon these caches (Arno and Hoff 1989).

The principal disease is white pine blister rust which is causing stands to decline throughout the species’ range, which is why the species was proposed for listing. In many parts of the range, stand mortality from this disease is greater than 50% (Nature Serve 2013). Other threats include the mountain pine beetle, fire suppression and successional replacement, and climate change (USFWS 2011, NatureServe 2013).

Trend and Potential Occurrence: Whitebark pine has a global ranking of G3G4; vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation and a state rank of S4; apparently secure, uncommon but not rare, some cause for long-term concern due to declines or other factors (NatureServe 2013). Stands of whitebark pine occur in all five SCNF Invasive Plant Management Zones.

Physaria didymocarpa var. lyrata (Salmon Twin Bladderpod) Biological Requirements: This species is found on scablands, shale banks, talus slopes, and gravelly soil (Mancuso 2006). It grows on steep south-facing slopes between 4,050 and 6,800 feet in the big sagebrush/bluebunch wheatgrass zone. It has been found growing on loose, but stable, substrate along roadcuts and other disturbance sites. It is generally found on sites with little plant cover (Moseley et al 1990b). Flowering is related to spring weather conditions; it usually begins in late May and goes through late June. If the weather remains cool and moist, flowering can extend throughout the summer. Threats such as mining activities, earth slumping, invasive plant invasion and herbicide application have been identified for this species.

Trend and Potential Occurrence: Salmon twin bladderpod has a global ranking of G5, secure- common, widespread and abundant; an infraspecific taxon rank of T1; and a state ranking of S1, critically imperiled because of extreme rarity or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state (NatureServe 2013).

This perennial mustard is endemic to Idaho. Until the 1980s, it was known only from one location on BLM land in the Salmon River Mountains (Moseley et al 1990b). However, other occurrences have since been found on BLM and FS land. Within the project area, Salmon twin bladderpod is known to occur in the Salmon and Lemhi zones.

Poa abbreviata ssp. Marshii (Marsh's Bluegrass) Biological Requirements: Marsh’s bluegrass grows on high elevation rocky alpine slopes in scree and talus (NatureServe 2013). It is only known from five occurrences range-wide. Threats to this species have not been identified (NatureServe 2013).

Trend and Potential Occurrence: Marsh’s bluegrass has a has a global ranking of G5, secure- common, widespread and abundant; an infraspecific taxon rank of T2; and a state ranking of S1, critically imperiled because of extreme rarity or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state (NatureServe 2013).

This grass is currently known from three states - Idaho, Nevada, and California. There is only one known population on SCNF, located within a roadless area in the Pahsimeroi-Lost zone.

Thelypodium repandum (Wavy-leaf Thelypody) Biological Requirements: Wavy-leaf thelypody inhabits steep shale banks derived from volcanic and metamorphic rocks where it is associated with bunchgrasses and herbaceous perennials across a wide elevational range (4,900 to 7,000 feet). It also inhabits road cuts and fills, being populated by populations further upslope (NatureServe 2013). It blooms from May through September (USDA Forest Service 1989). Identified threats include road maintenance, invasive plant control, mining activities, and OHV use (NatureServe 2013).

Trend and Potential Occurrence: The wavy-leaf thelypody has a global ranking G3 and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). This mustard is endemic to Custer County and a small part of Lemhi County in central Idaho. Populations are found in the project area only in the Upper Salmon zone.

Thlaspi idahoense var. aileeniae (Idaho Pennycress) Biological Requirements: Idaho pennycress (formerly known as Thlaspi idahoense var. aileeniae, Stanley thlaspi) is a perennial, low-growing, densely tufted, white flowered forb in the mustard family, flowering from May to July (USDA Forest Service 1989). Habitat is described as steep slopes on sandy and gravelly soil on sagebrush flats (USDA Forest Service 1989). The species appears to be locally abundant and has no identified threats (Moseley 1988). However, road maintenance and motorized off-route use could pose threats to populations of this species (Purvine, personal observation).

Trend and Potential Occurrence: Idaho pennycress has a global ranking of G3/G4 and an intraspecific taxon rank of T3; a range rank that is used to indicate the range of uncertainty of the status of the species. The status is approximately equal between being vulnerable, at moderate risk of extinction due to a restricted range, relatively few populations, recent and widespread declines, or other factors and apparently secure, uncommon but not rare, some cause for long-term concern due to declines or other factors and a state ranking of S3, vulnerable, at moderate risk because of restricted range, relatively few populations, recent and widespread declines, or other factors that make it vulnerable to range-wide extinction or extirpation (NatureServe 2013). Idaho pennycress is only found in the Stanley Basin where it is a common species in suitable habitat in the Sawtooth National Recreation Area (Moseley 1988). In the project area, it is found only in the upper Marsh Creek valley in the vicinity of Cape Horn in the Upper Salmon zone (Moseley 1988). It is possible that Idaho pennycress has a wider distribution, but it has not been discovered elsewhere in the project area to date.

Xanthoparmelia idahoensis (Idaho Range Lichen) Biological Requirements: Habitat for Idaho range lichen is restricted to calcareous badlands on gentle to moderate slopes that are barren to sparsely vegetated with shrub-steppe plants such as saltbush (Atriplex spp.) or sagebrush (NatureServe 2013). Threats to this species include off-route OHV use, livestock trampling and overgrazing, road maintenance and construction, or other ground disturbing activities (NatureServe 2013).

Trend and Potential Occurrence: The Idaho range lichen has a global ranking G1, critically imperiled, at very high risk of extinction due to extreme rarity, very steep declines, or other factors and a state ranking of S1, critically imperiled because of extreme rarity or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state (NatureServe 2013).

The Idaho range lichen is known from three localities; one each in Idaho, Colorado, and Alberta. There are several known sites of Idaho range lichen on calcareous badlands in the Lemhi River valley on private lands or BLM (NatureServe 2013). Forest Service land in the Lemhi River drainage is primarily located at mid to high elevations, which does not contain suitable habitat for Idaho range lichen (Cochrane, personal communication, 2014). There are no known populations of this species in the project area.