botanical resources technical report and biological evaluation...

1 Rock Creek Fuels and Vegetation – Botanical Resources Specialist Report and Biological Evaluation

Botanical Resources Technical Report and Biological Evaluation For

Rock Creek Fuels Reduction Project

Minidoka Ranger District Sawtooth National Forest

Prepared by: /s/ Thomas Stewart Date: ___6/20/2015___

Forest Botanist Sawtooth National Forest


Table of Contents Introduction .................................................................................................................................................. 3

Description of Project Alternatives and Project Design Features ................................................................. 3

AFFECTED ENVIRONMENT ............................................................................................................................ 7

NATIVE VEGETATION COMMUNITIES ............................................................................................ 7

(Key Issue) SAGEBRUSH COMMUNITIES ........................................................................................ 10

ESA LISTED PLANT SPECIES ............................................................................................................ 12

REGIONAL FORESTER’S SENSITIVE AND FOREST WATCH PLANT SPECIES ....................... 12

(Key Issue)NON-NATIVE INVASIVE NOXIOUS (WEED) PLANT SPECIES ................................. 15

POLLINATORS ..................................................................................................................................... 16

ENVIRONMENTAL CONSEQUENCES AND DETERMINATIONS ..................................................................... 16

Environmental Consequences ................................................................................................................. 17

NATIVE PLANT COMMUNITIES ....................................................................................................... 22

(Key Issue) SAGEBRUSH COMMUNITIES ........................................................................................ 23

ESA LISTED PLANT SPECIES ............................................................................................................ 24

REGIONAL FORESTER’S SENSITIVE AND FOREST WATCH PLANT SPECIES ....................... 24

REGIONAL FORESTER’S SENSITIVE & FOREST WATCH PLANT SPECIES .............................................. 27

(Key Issue) NON-NATIVE INVASIVE NOXIOUS (WEED) PLANT SPECIES ................................ 27

POLLINATORS ..................................................................................................................................... 29

CUMULATIVE EFFECTS ................................................................................................................................ 31

FOREST PLAN CONSISTENCY ....................................................................................................................... 33

LITERATURE CITED ...................................................................................................................................... 34

APPENDIX A ................................................................................................................................................. 38

Appendix B .................................................................................................................................................. 42


Introduction This specialist’s report addresses the anticipated effects to special status plant species within the area for the proposed Rock Creek project on the Minidoka Ranger District of the Sawtooth National Forest for a period of ten years. The proposed project area is located on the Cassia Division of the Minidoka Ranger District in the Sawtooth National Forest. The project area boundary includes 7,959 acres and is divided between Twin Falls County (4,084 acres) and Cassia County (3,875 acres). The project area is split between the Fourth Fork Rock Creek Subwatershed of the Upper Rock Creek Watershed and the Upper Goose Creek Subwatershed of the Upper Goose Creek Watershed, specifically including portions of (T14S, R18-19E) & (T15S, R18-19E) (Map 1). The geographic scope of the proposed action includes Management Area 11 – Rock Creek (4,629 acres), Management Area 13 – Trapper Creek/Goose Creek (3,074 acres), and Management Area 14 – Shoshone Creek (256 acres). The analysis area falls within three Management Prescription Categories (MPC); 4.1c Undeveloped Recreation: Maintain Unroaded Character with Allowance for Restoration Activities (22 acres), 4.2 Roaded Recreation Emphasis (7,564 acres), and 6.1 Restoration and Maintenance Emphasis within Shrubland and Grassland Landscapes (373 acres).

Description of Project Alternatives and Project Design Features Three alternatives were considered as described in the project record. They are summarized below and in Table 1. Alternative 1: No action alternative: The project would not be authorized or implemented. Alternative 2: The Proposed Action includes approximately 238 acres of mechanical treatments, a 1,241 acre prescribed fire treatment block targeting 496 acres of forested vegetation communities, 1,424 acres of hand treatment in conifer and aspen communities and 346 acres of timber stand improvements that would be applied to meet the purpose and need described above. (See Map 2 below for different treatments within the project area). Alternative 3: Limited Mechanical and No Commercial Timber Sale Treatment Alternative: This alternative would exclude mechanical treatment (with the exception of a 100 foot buffer around structures), increase the acres of hand treatment, and use hand treatment around the perimeter of timber stands instead of commercial thinning. Table 1. Project Alternatives Description

Treatment Type (Acres) Alternative Mechanical Hand Prescribed Fire Timber Stand Improvements

1 0 0 0 0 2 238 acres

Remove ladder fuels; masticate all material less than 6” DBH 14 acres Shaded fuel

1,424 acres Combination of aspen and conifer treatments

1,241 acre block targeting 496 forested acres Pile burning of areas with hand treatment

346 total acres 55 acres post and pole sales 279 acres of pre commercial thinning 12 acres patch cut harvest 0.3 miles temporary road construction


break. 3 20 acres

within 100’ of structures No shaded fuel break

1,642 acres

Same as Alt 2 0 acres No temporary road

Map 1. Rock Creek Fuels and Vegetation Project Vicinity


Map 2. Map of Treatments Proposed Under Alternative 2


Map 3.- Map of Treatments Proposed Under Alternative 3


AFFECTED ENVIRONMENT NATIVE VEGETATION COMMUNITIES The Potential Vegetation Group (PVG) for the analysis area was queried from Arcmap. Potential vegetation groups are based on the concept of habitat types. Habitat types are an aggregation of all land areas capable of producing similar plant communities at climax, which is the culminating stage of plant succession. The Potential Vegetation Group shares similar environmental characteristics, site productivity and disturbance regimes. There are 3 PVG’s in the analysis area based on the Sawtooth National Forest Land and Resource Management Plan (Forest Plan). PVG 11 (high elevation subalpine fir) covers 9 acres. This PVG is not believed to occur in the analysis area. PVG 70 (climax aspen) is found on 166 acres. This PVG is also not believed to occur in the analysis area. PVG 10 (persistent lodgepole pine) covers 4,523 acres. The 2012 Sawtooth Forest Land & Resource Management Plan (Forest Plan) uses environmental characteristics, site productivity, and disturbance regimes to describe desirable conditions for each Potential Vegetation Group (PVG) found within the project area. Current mapping of Forest PVG data was completed at the programmatic, Forest Plan scale utilizing a modeling process based on large-scale environmental characteristics. While this data layer is representative of spatial patterns at the programmatic scale, a site-specific review of existing vegetation indicates a need to refine the PVG designations within the project area. The current PVG geospatial designations classified 49% of the project area as PVG 10, persistent lodgepole pine. Site-specific review shows that a more accurate classification of the existing vegetation would use components of several PVG types. Therefore, this analysis references current vegetation types mapped by the 2012 Vegetation Classification, Mapping, and Quantitative Inventory (VCMQ). Vegetation is naturally patchy in the project area, with islands of coniferous forest surrounded by sagebrush/grass communities. Lower and mid-elevations feature sagebrush/grass communities. North and east aspects support subalpine fir and aspen communities. Lodgepole pine occurs in frost pockets and cold air drainages. Sagebrush/grass, subalpine fir, and aspen dominate at mid to high elevations. Based on the Sawtooth National Forest GIS cover type layer (USDA 2012) the project area is 66% forested, 33% non-forested, and approximately 1% Riparian and contains eleven distinct vegetation communities. The dominate vegetation communities within the proposed project area consist of forested vegetation (5,259 acres). The dominate forested communities are aspen (Populus tremuloides) (18%), followed by Aspen/Conifer (16%), lodgepole pine (Pinus contorta) (10%), Forested shrubland (10%), Conifer/Aspen (8%), and Subalpine Fir (Abies lasiocarpa) (5%). Most of the aspen stands are encroached upon by conifers and are regenerating poorly. Non-forested communities ( consist of Mountain Big Sagebrush (Artemisia tridentata Nutt. ssp. vaseyana) (15%), Mountain Shrubland (15%), Dwarf Sagebrush (2%), (Riparian (


small sized lodgepole pine are less likely to be infected because many of those trees regenerated after a fire killed the overstory trees and have no infected lodgepole pine near them. Table 2: Vegetation Communities in the Proposed Project Area

Vegetation Type Acres in Project Area Aspen 1,407 (18%) Aspen/Conifer 1,253 (16%) Conifer/Aspen 633 (8%) Lodgepole Pine 776 (10%) Subalpine Fir 429 (5%) Dwarf Sagebrush 144 (2%) Mountain Big Sagebrush 1,231 (15%) Forest Shrubland 761 (10%) Mountain Shrubland 1,182 (15%) Grassland 36 (


Riparian vegetation includes conifers and cottonwoods, hydric shrub, wet meadows, and herbaceous communities and is estimated at 42 acres. Rock Creek is the major stream in the analysis area. Forested riparian species include black cottonwood (Populus balsamifera), narrowleaf cottonwood (Populus angustifolia), and occasionally Douglas-fir (Pseudotsuga menziesii), and subalpine fir. The lower gradient channels are associated with a hydric grass and sedge component including native species such as reedgrass (Calamagrostis canadensis), tufted hair grass (Deschampsia caespitosa), mat muhly (Muhlenbergia richardsonis), foxtail (Alopecurus aequalis), few flowered spikerush (Eleocharis quinqueflora), Water sedge (Carex aquatilis), Nebraska sedge (Carex nebrascensis) and Baltic rush ((Juncus balticus), monkey flower (Mimulus guttatus, M. primuloides), Fringed grass of Parnassus (Parnassia fimbriata ), Jacob’s-ladder (Polemonium pulcherrimum), Brook saxifrage (Saxifraga

Map 4: Existing Vegetation


arguta), Arrowleaf groundsel (Senecio triangularis), Claspleaf twistedstalk (Streptopus amplexifolius), Western meadow-rue (Thalictrum occidentale), valerian (Valeriana edulis), and willow herb (Epilobium palustre). The riparian communities are integrated with willows (Salix wolfii, S. boothi, S. drummandiana), bog birch (Betula glandulosa), mountain alder, (Alnus incana), serviceberry (Amelanchier alnifolia), currants (Ribes spp.), and shrubby cinquefoil (Dasiphora floribunda). The forest shrub and mountain shrub communities cover approximately 1,943 acres. Mountain shrub communities include a mix of mountain big sagebrush (Artemisia tridentata var. vaseyana), chokecherry (Prunus virginiana), serviceberry (Amelanchier alnifolia), snowberry (Symphoricarpos oreophilus), bitterbrush (Purshia tridentata), green rabbitbrush (Chrysothamnus nauseosus), rubber rabbitbrush (Ericameria nauseosa),buckbrush (Ceanothus cuneatus) and currant (Ribes cereum). Non-woody species associations in shrub communities, as well as interspersed grassland communities include Great Basin wild rye (Leymus cinereus), bluebunch wheatgrass (Pseudoroegneria spicata), Idaho fescue (Festuca idahoensis), Letterman's needlegrass (Achnatherum lettermanii), Junegrass (Koeleria macrantha), foxtail barley (Hordeum jubatum), timber oatgrass (Danthonia intermedia), and Sandburg’s bluegrass (Poa secunda). Common forbs include yarrow (Achillea millefolium), pussytoes (Antennaria microphylla), sandwort (Arenaria capillaries), balsamroot (Balsamorhiza sagittata), lupine (Lupinus sps.), sego lily (Calochortus nuttallii), longleaf phlox (Phlox longifolia), and showy penstemon (Penstemon speciousus). The forest shrub community is similar to the mountain shrub community but has a mix of conifer species among the shrub species. Canopy cover in the mountain shrub communities occurs primarily in the >35% canopy cover class. In the habitats present in proposed project area, there are less desirable species including smooth brome (Bromus inermis), crested wheatgrass (Agropyron cristatum), intermediate wheatgrass (Thinopyrum intermedium), alfalfa (Medicago sativa), field brome (Bromus arvensis), bulbous bluegrass (Poa bulbosa), yellow sweet clover (Melilotus officinalis), dandelion (Taraxacum officinale), tumble mustard (Sisymbrium altissimum), timothy (Phleum pratensis) and Kentucky bluegrass (Poa pratensis). Microbiotic crust composed of lichens, bryophytes, algae, microfungi, cyanobacteria, and other bacteria are estimated to cover the sagebrush communities between 0 - 25% using pace transects of 10 meters. Other areas contained patchy occurrences of microbiotic crusts. Microbiotic crusts are important for soil stabilization, nutrient cycling, moisture preservation, and protection from invasive species.

(Key Issue) SAGEBRUSH COMMUNITIES Sagebrush habitats support a unique biodiversity. Several bird and mammal species are almost entirely dependent on sagebrush for survival: greater sage-grouse, Gunnison sage-grouse, sage sparrow, Brewer’s sparrow, sage thrasher, pygmy rabbit, and sagebrush vole. An additional 100 species of birds, 90 mammals, and 60 herptiles have a facultative association with sagebrush. At least one bird, 18 small mammals and 3 native ungulates consume sagebrush in their diets. Over 240 insects and 70 spiders and other arachnid species are associated with sagebrush (Welch 2005). At least 133 plants and 24 species of lichens are associated with sagebrush (Welch 2005), varying with geographic location, topography, soil, elevation, and climate.


Biological soil crusts are an important component of healthy semiarid sagebrush ecosystems. Made up of lichens, fungi, bacteria, cyanobacteria, algae, and moss, these fragile micro-communities bind and stabilize surface soil, recycle nutrients and make them available to plants, and provide micro-topography and moisture retention to aid seed germination (Belnap 1994).

Threats to sagebrush ecosystems are myriad and widespread, including urban and suburban development, energy development, agricultural conversions, livestock grazing and range treatments to improve range conditions for livestock, invasion of non-native vegetation and altered fire regimes, and encroachment by successional vegetation types. The loss and degradation of sagebrush ecosystems is significant and well-documented in western North America (Bock et al 1993, Knick and Rotenberry 2002). At least 10 percent of sagebrush has been lost to agriculture across its range, and in southern Idaho it has lost up to 99 percent (Knick and Rotenberry 2002). Much of the remaining sagebrush is highly fragmented, leading to deleterious edge effects on area-sensitive species. Invasions of exotic herbaceous vegetation such as cheatgrass have led to significant shrubland loss by dramatically altering natural fire regimes.

Although extreme weather, insects, and disease play a role in mountain big sagebrush population dynamics, fire is the dominant disturbance process in natural populations (Wright and Bailey 1982). Mountain big sagebrush plants are easily top-killed by fire and do not re-sprout from roots or crown. Population recovery can be relatively rapid when new plants establish from seeds that remain viable in the soil after burning (Wambolt et al. 2001). Recovery is delayed when dependent upon seed migration from unburned portions of the landscape (Welch 2005). Co-occurring shrubs and herbs vary in their ability to tolerate fire and in their strategies for post-fire recovery. Young coniferous trees are fire sensitive and are slow to re-colonize burned landscapes. Tree invasion is generally delayed until well after shrub recovery. On landscapes prone to tree invasion, mountain big sagebrush dominance is facilitated by fire-free intervals long enough to allow for big sagebrush recovery and short enough to prevent forest or woodland invasion and dominance (Miller & Rose 1999). The distribution of the mountain big sagebrush vegetation type is therefore largely dependent upon the spatial and temporal variation of fire frequency.

Within the project area there are two distinct sagebrush communities, mountain big and dwarf sage communities. Mountain big sagebrush communities are dominated by mountain big sagebrush (Artemisia tridentata ssp. vaseyana) and occur on approximately 1,231 acres (15%) of the project area. Dwarf sagebrush communities are dominated by little sage (Artemisia arbuscula ssp. arbuscula) and occur on 144 acres (2%) of harsher sites with shallow rocky soils within the project area. Common graminoids include oatgrass (Danthonia intermedia), Idaho fescue (Festuca idahoensis), slender wheatgrass (Elymus trachycaulus), mountain brome (Bromus marginatus), Sandburg’s bluegrass (Poa secunda), tufted hairgrass (Deschampsia caespitosa), pinegrass (Calamagrostis rubescens), and bluebunch wheatgrass (Pseudoroegneria spicata). Forb species include littleleaf pussytoes (Antennaria microphyllia), prickly sandwort (Arenaria capillarie), balsamroot (Balsamorhiza sagittata), silky lupine (Lupinus sericeus), sego lily (Calochortus nuttallii), and longleaf phlox (Phlox longifolia ssp. longifolia). Canopy coverage in mountain big sagebrush communities (mountain big sagebrush canopy coverage percentages using VCMQ 2012 data are greatest in the over 35% canopy cover class. This is > 50% of the mountain big sagebrush community in the Rock Creek Project. The second largest is in the 25%-34% canopy coverage that is estimated at 17% of mountain big sagebrush community.


In the 2012 Forest Plan revision, desired conditions for mountain big sagebrush communities targets canopy cover in the low to moderate class as described in the forest plan. Sagebrush canopy modeling using the VCMQ 2012 canopy cover data indicates that sagebrush coverage in the project area is not currently within the low to moderate canopy cover categories, and therefore is higher than desired condition. However, these spatial datasets have substantial data gaps for non-forested vegetation cover types and canopy coverage. Field observation and data collections indicate that in some areas the GIS models for non-forested vegetation are correct; however, we have identified areas mapped as sagebrush that are actually areas of encroaching conifer, late seral aspen stands with sagebrush in the understory, or a mountain shrub community. The Forest is currently undertaking quality and accuracy assessments to overcome these data deficiencies.

ESA LISTED PLANT SPECIES The Minidoka District provides potential habitat for one federally listed threatened terrestrial plant species. In September 2002, the USFWS removed Ute ladies'-tresses (Spiranthes diluvialis) from the Sawtooth National Forests’ 90-day Species List and noted that future biological assessments need not address the species because they believe the plant does not occur on the Forest (USFWS 2002, 1-4-02-SP-911). However, as part of rare plant surveys, Ute ladies’-tresses orchid is surveyed for on projects within the Sawtooth National Forest. Due to direction from the USFWS and because Ute ladies’-tresses orchid are not known to occur within the proposed action area, they will not be discussed further in this analysis. The Minidoka District provides potential habitat for one species on the candidate list for ESA protection. Presently, seven populations of Goose Creek milkvetch (Astragalus anserinus) are known for Idaho. All populations occur on BLM land, with several extending onto adjacent private lands. No populations are known for the Sawtooth National Forest, although most populations are within a few miles of the south east boundary of the Cassia Division of the Minidoka District (Mancuso 1991). The proposed project does not contain any potential habitat for Goose Creek milkvetch and it will not be discussed further in this report.

REGIONAL FORESTER’S SENSITIVE AND FOREST WATCH PLANT SPECIES The Sawtooth National Forest has known occurrences and provides habitat for 45 Regional Forester’s Sensitive Plant Species and Sawtooth Forest Watch Plant Species (See Appendix A for complete list). The Minidoka District of the Forest has known occurrences and/or provides habitat for 12 of these plant species. Table 3- Minidoka Ranger District’s Regional Forester’s Sensitive and Forest Watch Plant Species

Common Name Scientific Name Status

Grouse Creek Rockcress Arabis falcatoria Watch Armed Prickly Poppy Argemone munita Watch Goose Creek Milkvetch Astragalus anserinus Sensitive Slender Moonwort Botrychium lineare Sensitive Christ’s Indian Paintbrush Castilleja christii Sensitive Malheur Cryptantha Cryptantha propria Watch Davis’ Wavewing Cymopterus davisii Sensitive


Desert Buckwheat Eriogonum desertorum Sensitive Simpson’s Hedgehog Cactus Pediocactus simpsonii Watch Idaho Penstemon Penstemon idahoensis Sensitive Cottam cinequefoil Potentilla cottami Sensitive Rock Violet Viola lithion Watch

Idaho Heritage Database records did not show any known occurrences near or in the analysis area for any of the above listed species. There is potential for two species to occur within the project area based on habitat requirements for the species. Surveys done during the 2015 field seasons found no special status plants within the project area. Surveys were not 100% inclusive of the project area and focused on areas of highest potential to contain rare plants and their habitat. Due to no habitat within the project area 10 sensitive and watch species do not have potential to occur. They will not be discussed further in this analysis. The two species with potential to occur will be further analyzed.

Slender Moonwort (Botrychium lineare) Status of Species In July 1999, the U.S. Fish and Wildlife Service was petitioned to add the slender moonwort to the List of Threatened and Endangered Plant Species. The Service published the 90-day petition finding and initiated a 12-month status review in May 2000. In June 2001, they published a finding that supported listing slender moonwort, but was precluded by work on higher priority listing actions and placed on the candidate species list (Federal Register June 6, 2001 Vol. 66, number 109). December 6, 2007 USFWS removed slender moonwort removed because it is more abundant than previously recognized and there is insufficient information to justify its continued candidate status. (Federal Register December 6, 2007 Vol. 72, No. 234). It is currently a Regional Forester’s Sensitive species. Habitat Factors A specific habitat description for the species is problematic because of its current and historically disjunct range of more than 107,000 square miles. Some researchers consider B. lineare a habitat generalist that may be an opportunistic colonizer since it is found in a variety of natural sites, and several extant population sites are found in man-made disturbed sites (Federal Register December 6, 2007 Vol. 72, No. 234). Slender moonwort is found in a variety of montane forest or meadow habitats described as “deep grass and forbs meadows, under trees in woods, and on shelves on limestone cliffs, mainly at higher elevations” (Wagner and Wagner 1994), but they also state that to describe a typical habitat for this species would be problematic since the known sites are so different. Other slender moonwort sites occur in grass- to forb-dominated openings in forests characterized by cone-bearing trees such as pine, spruce, and fir species (Brooks, Wallowa-Whitman National Forest, 2000). Three of the known Montana slender moonwort populations occur on roadsides in early seral habitat. Description Slender moonwort is a small perennial fern with a pale green leaf (trophophore) 2-7 inches long. Leaf segments are typically linear and divided or forded at the ends. The sporophore (spore-bearing structure) is 1 to 2 times the length of the trophophore with a single main axis.


Botrychium spores are small and lightweight enough to be carried by air currents. This dispersal mechanism may explain the broad and often disjunct distribution patterns exhibited by moonworts (Vanderhorst 1997). All Botrychium species are believed to be obligately dependent on mycorrhizal fungi throughout their life cycle. A fungal associate is present within the plant at the earliest stages of development, and there are no reports of successful completion of the Botrychium life cycle without mycorrhizal fungi. Very little information exists regarding the specificity or habitat requirements of the mycorrhizal fungi that are associated with moonworts (Vanderhorst 1997). Similar to orchids, Botrychium species can remain dormant for 1 or more years, and cannot be identified with certainty in their immature stages. Factors of Decline/Threats Slender moonwort is a perennial ferns. It is known to occur in a wide range of habitats including alpine meadows to road shoulders. Some of these habitats are highly susceptible to non-native plant species invasions and are areas treated with chemicals regularly. Threats to this species include: trampling from recreation uses recreation uses, off road vehicle use, maintenance or construction of trails and roads, timber sales and fuels projects, and effects of domestic livestock grazing. The invasion of non-native plant species creating competition in its habitat is another threat.

Simpson’s Hedgehog Cactus (Pediocactus simpsonii) Status of Species Simpson’s Hedgehog Cactus is a Forest Watch species. There are three generally recognized varieties of Pediocactus simpsonii, one of which is var. robustior. Hitchcock (1961a) states that var. robustior is the only one of the three found in the Pacific Northwest, the others being confined to points south and east of Idaho. There are 41element occurrences (EO) known in Idaho and five of these are on the Minidoka District. The closest EO is #5 and is located six miles east of the project area boundary. Habitat Factors In Idaho, Simpson's hedgehog cactus occurs in a variety of open, rocky habitats, and across a wide range of elevations, from 1600 to 8500 feet. It is known from canyon ridges, benches and rims at low- to midelevations, as well as exposed, mountain ridgecrests. Soils are generally shallow, rocky and well drained. Documented parent materials include basalt, rhyolite and quartzite. Sites also tend to be stable and not subject to migration. Throughout the state it can be associated with a variety of sagebrush, grassland or juniper communities. It occurs on all aspects, although mostly warmer exposures, and from flat to steep slopes.

Description This spiny cactus grows singularly or in clusters. It is depressed to more or less subglobose in shape, with stems up to 5 inches in diameter. Stems are longitudinally ribbed, with the ribs bearing tubercules (small, rounded projections). Plants contain numerous whorls of sharp, stout, whitish to yellowish or reddish-brown spines up to nearly 2 inches long. Flowers are showy, up to 1inch in diameter, occur in a crowded ring around the top of the plant, and are usually rosy-pink in color, although sometimes yellowish-green or white. Fruits are small, subglobose to cylindric in shape, and splitting when ripe to discharge the large blackish seeds


Factors of Decline/Threats Potential threats at some populations include overcollecting, and habitat destruction or degradation. Overall, the species future looks secure in Idaho under current land management practices.

(Key Issue)NON-NATIVE INVASIVE NOXIOUS (WEED) PLANT SPECIES Canada thistle, cheatgrass, and diffuse knapweed are known to occur in the project area. Scotch thistle, Russian knapweed, black henbane, musk thistle, leafy spurge and whitetop have potential to occur in the project area, particularly along main travel ways and in areas of high activity. The introduction of new weed infestations and the spread of cheatgrass are a concern for this project. An estimated 26 percent of the project area is highly susceptible to establishment and spread of noxious weeds and exotic plants. Scotch thistle (Onopordum acanthium) It is a biennial plant, producing a large rosette of spiny leaves the first year. In the second year, the plant grows 1.5- 7 feet tall and a width of up to 4 feet. Establishes in disturbed areas, riparian areas, and dry sites and has the potential to spread rapidly. This species can be found in riparian areas, along roadsides, and within disturbance on dry sites within the project area. Idaho State Containment List. Russian knapweed (Acroptilon repens) is a creeping, herbaceous perennial of foreign origin that reproduces from seed and vegetative root buds. It can form dense, single species stands over time due to competition and allelopathy. This species could be along roadsides and within disturbed areas within the project area. Idaho State Control List. Diffuse knapweed (Centaurea diffusa) is a biennial to short-lived tap rooted perennial that readily establishes on disturbed soils, outcompeting native plants for moisture and nutrients and is difficult to control. There are Diffuse knapweed infestations along the Rock Creek road and on the Magic Mountain Ski area in the proposed project area. There are no proposed treatments in areas known to contain diffuse knapweed. Idaho State Containment List. Black Henbane (Hyoscyamus niger) is an annual or biennial plant that grows up to 3 feet tall from a single taproot. Seeds are small and black, and prolific seed production proliferations the spread of this plant, as a single plant can produce up to half a million seeds. This species occurs adjacent to the project area it is prevalent in pastures, fencerows, roadsides and waste areas. Idaho State Control List. Musk thistle (Carduus nutans) is an annual or biennial plant that grows up to 3 feet tall. A single plant can produce up to 120,000 seeds, which are wind dispersed and the seeds may remain viable in the soil for over ten years. This species can be found along roadsides and in riparian areas within the project area. Idaho State Control List. Canada thistle (Cirsium arvense) is a creeping rooted perennial that occurs in riparian areas. It is highly mobile from wind-born seeds and the soil seed bank holds Canada thistle seeds that germinate and grow when areas are disturbed. This species can be found in riparian areas and along roadsides within the project area. Idaho State Containment List.


Leafy spurge (Euphorbia esula) is an erect perennial up to 2.5 feet tall with roots exceeding 20feet in depth. This species can be found in riparian areas and along roadsides adjacent to the project area. Idaho State Containment List. Whitetop (Cardaria draba) is a perennial up to 2 feet tall with dense clusters of white flowers at the top of each stem. It reproduces by seeds and by horizontal creeping roots. This species can be found in riparian areas, disturbed sites, and along roadsides in the project area. There are no proposed treatments in areas known to contain whitetop. Idaho State Containment List. Cheatgrass (Bromus tectorum) is an annual grass found in many disturbed sites, roadsides, and dry slopes. Cheatgrass is not a listed noxious weed in Idaho but is abundant across south facing slopes, road, parking areas, trails, and other areas with continual disturbances. This is considered a difficult species to eradicate once established and often becomes a monotypic community out competing native species. Cheatgrass infestations occur within the proposed project area in isolated areas associated with recreation, livestock and wildlife uses, and roads. The Sawtooth Integrated Weed Management Program uses mechanical, biological control agents, and herbicide applications for the control of noxious and invasive species on the Minidoka District.

POLLINATORS Very little information on insect pollinator species occurrence and population trends is known on the Minidoka District. No known surveys have been conducted. Species present are most likely typical for the climate and plant communities present. These include species of bees within the families Apidae (bumblebees) Colletidae, Andrenidae, Halictidae (solitary bees), Megachilidae (leafcutting bees), Anthophoridae (digger bees and carpenter bees) and many species within the Order Diptera (flies) (Tepedino 2001). Many species of plants rely on insects for pollination. Some species of plants are pollinated by many species and others are more specific depending on one pollinator species. Plant and pollinator diversity have been shown to be positively correlated. Recent evidence suggests that many species of insect pollinators may be in decline due to many factors, including habitat alteration and fragmentation, pesticides, and competition from nonnative species (Kearns et al. 1997, Allen-Wardell et al. 1998). Native plant species diversity is essential to maintain pollinator populations.

ENVIRONMENTAL CONSEQUENCES AND DETERMINATIONS

Analysis Methods This document analyzes Threatened, Endangered, Candidate, Sensitive & Watch (TECSW) plant species known occurrences and their probability to occur in potential habitat. Native vegetation communities, nonnative and invasive plant species, and pollinators are also analyzed in this document. Field surveys for the project area were conducted during the 2015 field season within the project area. Due to the size of the project are the surveys did not cover the entire area. Inventories focused on areas with an increased chance of containing rare plants species. These


areas were wet meadows, riparian areas, sagebrush habitat, and rock out cropping and cliffs. Characteristics considered in this analysis include species specific requirements, proposed activities potential disturbances, existing native plant community health, soil type, topography, aridity, landscape accessibility, and other disturbances occurring in the area.

Environmental Consequences The environmental consequences associated to vegetation and potential effects to rare plant species and habitats from the proposed project are described in the following paragraphs. These effects include vegetation, soil and hydrological disturbances, and the introduction and establishment of noxious and non-native invasive plant species. Although known occurrences of rare plant species would be avoided with compliance to project design features and best management practices. It is possible there are unknown occurrences in areas of potential habitat that could be affected by activities associated with the proposed action. Vegetation disturbances include burning, removal, uprooting, and trampling all which could affect TECSW plants, an increase in annual and monoculture communities which results in regressive plant succession. Soil compaction by equipment could reduce the supply of oxygen to the root system. These disturbances could kill or stress the TECSW plant species making them more susceptible to disease and insect attack. Soil compaction created by equipment and vehicles alters the rate at which water penetrates the soil surface and reduces the soil moisture holding capacity and consecutively increases run off, and soil erosion. Decreased water infiltration changes soil nutrients and organic matter available for plants (Facelli & Pickett 1991) and reduces plant productivity. An increase in overland flow into the surrounding habitat as a result of soil compaction could saturate soils and cause lack of oxygen filtration and nutrient deficits which when combined reduces plant productivity and vegetative cover creating a negative progression that further degrades both TECSW plant species habitat, and native plant communities. Temporary transportation corridor construction and maintenance activities facilitate spread of plant seed by way of soil and material movement, vehicles, tools, humans, and equipment. When vehicles, tools, humans and equipment encounter noxious and non-native invasive plant species there is a risk of spreading the seed or plant parts to non-infested areas. All sites with noxious and non-native invasive species have viable seed in the soil and movement of the soil scarifies the seed and aids in germination as well as moving seed to other locations on vehicles, equipment, tools, humans, domestic livestock, wildlife, or natural vectors. Ground disturbance within existing noxious non-native invasive plant species stimulate stoloniferous root growth, increasing the density of the infestation. Invasive plant population spread can indirectly displace or reduce native plant populations in early post-logging succession by seedling or mature plant competition, preemption of space, or modification of vegetation structure and microhabitats. Non-native species invasion impacts are not narrowly confined to timber harvest areas or road maintenance areas; they actively spread along disturbed corridors or patches, and increase invasion pressures (seed rain) on even intact plant communities.


The introduction of noxious and non-native invasive plant species as a result of the proposed action activities into native plant communities could potentially reduce the competitive and reproductive capacities of native species, shift community composition, alter available resources, displace less vigorous native species ensuing regressive plant succession, and an increase in annual and monoculture communities. Consequently, altered native plant communities affect TECSW plant species existence. Potential indirect effects associated with noxious weeds and non-native invasive plant species infestations may include loss of wildlife habitat, soil erosion due to shorter-lived annual species invasions, and consequent increased fire susceptibility due to dry dead stands of annual non-native invasive plant species (e.g., cheatgrass stands). Left untreated, infestations of noxious weeds or non-native invasive plant species sites would increase, eventually eliminating the native vegetation and replacing the plant regime with an undesirable plant community. As a whole, the design features requiring noxious weed and invasive plants treatments are implemented to benefit TECSW plant species, potential habitats, and native plant communities. However, chemical treatment could damage or kill individual TECSW species if their occurrences are unknown in treatment areas. Vehicles and equipment leaving the analysis area that have worked in an area infested with noxious weeds or non-native invasive plant species, if not washed prior to leaving, may transport and spread noxious weeds or non-native invasive plant species to other locations. Livestock and wildlife in the area also could transport noxious weeds or non-native invasive plant species seed in their fur and hooves. Birds that have eaten seeds and wind dispersion are additional possible seed vectors. A change in plant community composition could occur as fire can promote plant species that are well adapted to fire and suppress plant species that are poorly adapted to fire. As a result, fire can cause dramatic and immediate changes in species composition and diversity (Duchesne 1994). A change in plant community structure occurs as fire consumes dead and living plant material, resulting in changed horizontal and vertical distribution of plants within a community. Stand-replacement fires that occur in forests, woodlands, shrublands, and grasslands kill above and below ground parts of the dominant vegetation, changing the structure substantially (Brown 2000). Low intensity fires often kill above ground parts, temporarily changing structure. A change in the vegetation patterns; Fires can create more structurally diverse landscapes that include patches that differ in vegetation composition and stand structure (Turner and Romme 1994). Over time, the post-fire plant community is further influenced by subsequent interactions with other plants, activities of other taxa (i.e., insects, pathogens, grazing ungulates), climatic variables, environmental changes, and other natural or anthropogenic disturbances (Brown 2000). Overall, the traits and mechanisms for plant survival and response to fire described above apply to all terrestrial plants regardless of their origin or perceived value as a desirable or undesirable


species. The direct effect of fire on noxious and non-native invasive plant species depends on the compatibility of the plant’s traits with the characteristics of the fire. Plant community composition immediately following a fire results from the interaction between fire severity and a plant’s regeneration strategies (Brown 2000). Noxious and non-native invasive plant species may regenerate or germinate from on-site propagules as well as propagule from off-site sources. If the fire area has known infestations of noxious and non-native invasive plant species, crowns, seeds, and vegetative propagules may survive and thrive following low to moderate severity burns. More severe fires often result in a delayed on-site regeneration from resprouting or surviving seeds because of the mortality or damage to these sources by fire (Stickney 1990). If the fire area does not have known infestations of noxious and non-native invasive plant species, lower severity fires areas may be more resistant to invasion by new plant species from off-site sources because most preexisting native plants resprout and quickly occupy the site. Severely burned areas are often left with large areas of bare mineral soil, providing niches where noxious and non-native invasive plant species can readily establish from off-site sources. Exposed ground surfaces, a flush of nutrients, and high light and low shade may favor regrowth and expansion of noxious and non-native invasive plant species in burned areas. Because of their early germination and rapid growth rates, noxious and non-native invasive plant species may quickly capture newly available resources. Invasive plant species (i.e. cheatgrass) may create conditions that alter the characteristics of fire regimes such as spread patterns, intensity, frequency, and seasonality (Brooks et al. 2004). This occurs when invading plants are different in their life-form or phenology from the native plants and thus change the continuity, biomass, and vertical distribution of fuels in a community (D’Antonio 2000). Changes in fire regimes have the potential to further impact the remaining plant community by suppressing species that are poorly adapted and promoting species that are well adapted to fire patterns under the new regime. Access road construction and decommissioning would result in areas of ground disturbances. Disturbances include soil compaction, displacement, and subsequent soil erosion. Soil compaction created by equipment and vehicles alters the rate at which water penetrates the soil surface and reduces the soil moisture holding capacity and consecutively increases run off, and soil erosion. Decreased water infiltration changes soil nutrients and organic matter available for plants (Facelli & Pickett 1991) and reduces plant productivity. Vegetation disturbances include removal, uprooting, and trampling. If a TECSW plant species occurs adjacent to the activities it could be crushed, removed, or the root systems could be disturb causing stress or death.

Mechanical The removal of vegetation during commercial thinning activities will create ground disturbance. Equipment and vehicles used during commercial thinning activities could kill or injure TECSW plant species. The removal of vegetation will alter forested habitats making them less suitable for TECSW plant species that occupy forested habitat, and reduce the availability of potential habitat for these species in the project area.


Mechanical thinning and patch cut activities within existing noxious non-native invasive plant species could stimulate stoloniferous root grow increasing the density of the infestation, and spread seed with the movement of soil. All sites with noxious and non-native invasive species have viable seed in the soil and movement of the soil scarifies the seed and aids in germination as well as moving seed to other locations on vehicles, equipment, tools, humans, domestic livestock, wildlife, or natural vectors. Mechanical thinning and patch cut activities create areas of disturbed soil optimal for colonization of noxious non-native invasive plant species. Non- native invasive species could alter native community composition, increase annual species that compete for resources eventually excluding less vigorous species ensuing regressive plant succession, and monoculture communities.

Hand Thinning (using chainsaws) The removal of vegetation during hand thinning activities could kill or injure TECSW plant species. The removal of vegetation during hand thinning activities will alter forested habitats making them less suitable for TECSW plant species that occupy forested habitat, and reduce the availability of potential habitat for these species in the project area. Within the Hand thinning units (Map 2, Map 3) conifer species may be cut by chainsaw within aspen stands. After the conifers have been thinned out of the stand prescribed fire may be used to promote aspen regeneration. This could result in burning, removal, uprooting, and trampling of TECSW plant species.

Pile Burning Pile burning generates scars with increased susceptibility to noxious non-native invasive plant species. Pile burning scars often remain unvegetated (Covington et al. 1991) or become colonized by noxious non-native invasive plant species (Dickinson & Kirkpatrick 1987) or early successional species of disturbed habitats. Pile burning significantly reduces the viable seed bank, propagule densities of arbuscular mycorrhizae fungi as well as alters soil properties (Korb et al. 2004).

Lop and Scatter The scattering of hand harvested understory vegetation during hand thinning activities will alter forested habitats making them less suitable for TECSW plant species that occupy forested habitat, and reduce the availability of potential habitat for these species in the project area. TECSW plant species could be killed or injured during lop and scatter activities. Lop and scatter fuels created by the harvest, would be more likely to burn as a surface fire than crown torching fire ultimately retaining more forested habitat but increasing surface temperature of the fire.

Temporary Access Routes/Landings/Skid Trails - A temporary overland travel route (up to 0.3 miles) Travel routes, landings and skid trails would remove vegetation, litter layer, expose mineral soil, and create soil disturbances. Equipment and vehicles would create soil compaction. TECSW plant species could be killed or injured during construction and use. Landing sites, skid trails and the temporary access routes would avoid riparian areas. The temporary access route would be repaired and naturalized (e.g. decompacted, woody material added and seeded) after the proposed activities concluded.


Studies addressing the effects of silviculture treatments on exotic plants found an increase in at least one noxious non-native invasive plant species following treatment involving the construction of new travel routes (access routes, landings, skid trails) and increased use of established roads (Forman & Alexander 1998; Parendes & Jones 2000; Gelbard & Belnap 2003). Whether the new routes played a role in these increases is unknown. However, roads can facilitate invasion into treated areas by acting as points of establishment for noxious non-native invasive plant species and sources of propagules that increase the potential for spread. Landing sites, skid trails, and travel routes within existing noxious non-native invasive plant species could stimulate stoloniferous root grow increasing the density of the infestation, and spread seed with the movement of soil. All sites with noxious and non-native invasive species have viable seed in the soil and movement of the soil scarifies the seed and aids in germination as well as moving seed to other locations on vehicles, equipment, tools, humans, domestic livestock, wildlife, or natural vectors.

Prescribed Fire Treatments Prescribed burning has direct and indirect effects on the environment. Burning techniques and timing of burns can be varied to alter fire effects. Fire may injure or kill part of a plant or the entire plant, depending on how intensely the fire burns and how long the plant is exposed to high temperatures. In addition, plant characteristics such as bark thickness and stem diameter influence the susceptibility to fire. Small trees of any species are easier to kill than large ones. Damage can occur from the extended smoldering of duff around the root collar. Such damage is especially likely in previously unburned, mature trees where a deep organic layer has accumulated. Whenever heat penetrates into the soil, feeder roots and beneficial soil organisms are likely to be killed. Damaged pines are more susceptible to bark beetle attack, especially if adverse weather conditions (e.g. drought) after the burn compound any loss in tree vigor. However, many observers report less insect damage in stands that undergo periodic prescribed burns than in stands where fire has been excluded. The effect of fire on plant species varies significantly between, and within, species. Additionally, responses are influenced by a variety of fire parameters including intensity, severity (e.g., amount of organic matter consumed), residence time, soil heating, season of burn, and time since last fire, all of which can vary significantly. These variations could cause differences in the response of individual species and the community as a whole. Moreover, numerous physical and climatic factors (e.g., fuel condition, weather, slope, and aspect) as well as biological factors (plant morphology and physiology) will influence post-fire effects on individual plants and communities. This includes direct effects such as the ability of individual species to resist the heat of a fire (depending on age and seasonality) and the mechanisms by which they recover after fire. High temperatures during fires can directly damage plant tissue and propagules through combustion, and indirectly damage plant physiological processes through radiant heating (Levitt 1972). The likelihood of plant and seed mortality by fire depends on the duration of exposure to lethal temperatures. Mortality can occur with short exposure to high temperatures (Martin 1963), whereas death at lower temperatures often requires a longer exposure (Ursic 1961).


A plant’s survival is influenced by its growth stage at the time of the fire. Plant tissues, especially growing points (meristematic tissue), are most susceptible when actively growing (Wright and Bailey 1982). Mortality depends on the amount of meristematic tissue killed. Some plants are able to survive a fire because their growing points and propagules are structurally, spatially, or temporally protected from exposure to lethal temperatures (Miller 2000). For example, fire-resistant plant species like Ponderosa pine (Pinus ponderosa) suffer little damage from direct exposure to a surface fire due to thick bark that protects living tissue and seeds that reside in the canopy, high above the fire’s flames. Low-growing plants and plants that sprout from roots, soil surface crowns, and rhizomes often survive and resprout because their meristematic tissues and reproductive structures are near the soil surface where temperatures are generally cooler during a fire. Other plants may avoid mortality simply by completing their life cycle before or after a fire occurs. Fire-intolerant species tend to be highly flammable and completely destroyed by fire. Some fire-intolerant species such as hollyhock (Iliamna rivularis) have large, long-lived fire-activated seedbanks that germinate, grow, and mature rapidly following a fire. Predicting plant species and community response to fire is difficult. An individual plant’s response to fire is a result of the local fire conditions and a plant’s traits and growth stage. Plant community response is a product of the responses of all plant species in a burned area and their interactions with each other, existing environment, and the changed environment (Miller 2000). In addition to external factors such as post-fire weather, post-fire herbivory, parasites, pathogens, and plant competition can also determine how individual species and communities will respond to fire.

NATIVE PLANT COMMUNITIES Environmental Consequences Native plant communities in the analysis area would incur vegetation and soil disturbances during implementation of proposed activities. Direct vegetation disturbances include burning, removal, uprooting, and trampling. Indirect disturbances include soil compaction, hydrology alteration, weed introduction and spread, and microbrial crust disturbances. Determinations Alternative 1- No Action means no projects would occur within the analysis area. All effects would continue to exist as they have in the past. The No Action Alternative would have no direct impact on native plant communities. Current levels of risk of negative effects from non-native invasive and noxious plant species would continue to exist under the no action alternative. Fuels would continue to increase over time and contribute to a continued aging and deterioration of vegetation communities. Activities that continue as they have in the past and currently occur include construction and use of system and non-system roads, past and present livestock grazing, pesticide and herbicide application, recreation and non-recreation special use permitted activities, developed recreation, water diversion structures, irrigation (inadvertent), current and past timber harvest, current and past mining activity, personal use firewood cutting, and dispersed recreation (including skiing and snowmobiling). Existing non-native and noxious plant species continue to produce a seed source in the area. Seed from these locations would continue to be transported into adjacent and currently intact communities via vehicles, humans wildlife, livestock, and by non-anthropogenic agents (e.g. rodents, wind, and water).


Alternative 2 - Impacts from prescribed fire could occur across 1,241 acre of the project area (Map 2) and 100 acres to burn piles created from thinning activities (both mechanical and hand). Prescribed fire would not be used in the 545 acre zone marked as fire avoidance (Map 2) due to erosion potential, weed infestation and spread, and ability to control the burn. The burn would be targeting 496 acres of the larger burn area. Hand treatments areas and pre-commercial thinning would occur over 1,424 acres and would be done by individuals using a chainsaw. There are 980 acres of aspen and aspen/conifer mix within hand treatment areas that could be burned. Impacts from mechanical treatments would occur in areas identified as such and as shaded fuel break, post and pole, and patch cuts which would occur over a total of 598 acres. These activities would also impact approximately 4 additional acres for Temporary Access Routes, Landings, and Skid Trails. All activity areas (Map 2) could have some amount of drop, lop, and scatter activities which could impact native plant communities as described above. Alternative 2 would create short term disturbances in native plant communities. Compliance with project design criteria, mitigation measures and best management practices would most likely cause long-term benefits in native plant communities including improved ecological health and vigor as new plants replaced older late seral plants. Alternative 3 - Impacts of prescribed fire activities and pile burning in Alternative 3 are identical to Alternative 2. Impacts as described above would occur on 1,241 acres with 496 acres being targeted for burning. Slash from thinning activities would be piled and burned resulting in an additional 100 acres impacted by fire. Alternative 3 would have no shaded fuel break, no post and pole, and no patch cuts removing these impacts from 319 acres as compared to Alternative 2. The hand treatments of Alternative 3 would occur over 1,642 acres verse 1,424 in Alternative 2. Alternative 3 hand treatment unit encompasses 1,185 acres of aspen and aspen/conifer mix that could be targeted for burning. The mechanical treatments would be limited to 100 feet from structures and would impact 20 acres. Alternative 3 would create short term disturbances in native plant communities. Compliance with project design criteria, mitigation measures and best management practices would most likely cause long-term benefits in native plant communities including improved ecological health and vigor as new plants replaced older late seral plants.

(Key Issue) SAGEBRUSH COMMUNITIES Environmental Consequences Sagebrush communities in the project area are at greatest risk of impacts from prescribed burning escaping target burn areas. Fire may injure or kill part of a plant or the entire plant, depending on how intensely the fire burns and how long the plant is exposed to high temperatures. Whenever heat penetrates into the soil, feeder roots and beneficial soil organisms are likely to be killed. High intensity fire can result in hydrophobic soils that repel water and reduce infiltration. Sagebrush communities, especially dwarf communities, are susceptible to weed invasion after fire. High intensity fires hinder a community’s ability to resist weed invasion.


Fire can also have beneficial impacts to sagebrush communities. Burning sagebrush communities can increase soil nutrients, which is one of the main reasons burning often results in a 2- to 3-fold increase in herbaceous production (Davies et al. 2014). The removal of the dominant plant species may increase plant diversity. Plant diversity influences community stability and other trophic levels. Overall burning can create spatial and temporal heterogeneity in sagebrush communities (Davies et al. 2014). Indicators

• Estimated acres of sagebrush habitat within the contingency burn area. Determinations Alternative 1- No Action means no projects would occur within the analysis area. All effects would continue to exist as they have in the past. The No Action Alternative would have no direct impacts on sagebrush communities. Current levels of risk of negative effects from non-native invasive and noxious plant species would continue to exist, under the no action alternative. Fuels would continue to increase over time and contribute to a continued aging and deterioration of sagebrush communities. Existing non-native and noxious plant species continue to produce a seed source in the area. Seed from these locations would continue to be transported into adjacent and currently intact communities via vehicles, humans wildlife, livestock, and by non-anthropogenic agents (e.g. rodents, wind, and water). Alternative 2 - Impacts from prescribed fire could occur across 1,241 acre of the project area and 415 acres (33%) of this is in the mountain big sagebrush community and 103 acres (8%) is in dwarf sagebrush community. Any burning of sagebrush would be unintentional as it is not a target community (Map 2). Per mitigation measures if 20 continuous acres of mountain big sagebrush community and/or 5 acres of dwarf sagebrush community burned it would be evaluated for reseeding. Prescribed fire would not be used in the 545 acre zone marked as fire avoidance due to erosion potential, weed infestation and spread, and ability to control the burn. Other activities proposed in Alternative 2 could cause incidental disturbances to sagebrush communities. However, since the proposed actions are not occurring within this community impacts would be negligible. Alternative 2 could create disturbances in sagebrush communities. Compliance with project design criteria, mitigation measures and best management practices would most likely cause neutral to long-term benefits in sagebrush communities. Alternative 3 - Impacts from Alternative 3 on sagebrush communities would be identical to Alternative 2.

ESA LISTED PLANT SPECIES

REGIONAL FORESTER’S SENSITIVE AND FOREST WATCH PLANT SPECIES

Slender Moonwort (Botrychium lineare) Environmental Consequences


Considering the diverse habitats slender moonwort is known to occupy (i.e. meadows, open forested areas, high elevation cushion plant habitats, and manmade habitats such as road shoulders), there are many areas of potential habitat that exist within the analysis area. No individual slender moonworts were identified during project surveys, however, the fact that moonworts remain dormant for 1 or more years, and cannot be identified with certainty in their immature stages creates risk that they may exist in areas but have not been identified. All soil disturbing activities associated with project activities within the potential habitat could alter mycorrhizal fungi and soil conditions necessary for the existence of this species. Soil disturbing activities could destroy individuals and the reproductive spores that exist in the soil. Determinations Alternative 1- No Action means that no specific management activities proposed by the Rock Creek Project would occur. Ongoing and permitted uses on National Forest system lands would continue within the project area. Management activities previously approved by other environmental analyses and decision documents would also continue to be implemented. Impacts to slender moonwort would continue to exist as they have in the past. The No Action Alternative would have No Impact on slender moonwort. Alternative 2- Impacts from prescribed fire could occur across 1,241 acre of the project area (Map 2) and 100 acres to burn piles created from thinning activities (both mechanical and hand). Prescribed fire would not be used in the 545 acre zone marked as fire avoidance due to erosion potential, weed infestation and spread, and ability to control the burn. The burn would be targeting 496 acres of the larger burn area. Given the estimated 10 year time frame for implementation, treatments may need to be modified based upon non-project influenced changes in vegetation conditions (i.e. wildfire, insect or disease epidemic). The acres treated would be adjusted as needed to ensure the overall effects are consistent with the management objectives to move toward desired conditions. Hand treatments and pre-commercial thinning would occur over 1,424 acres and would be done by individuals using a chainsaw. Impacts from mechanical treatments would occur in areas identified as such and identified as shaded fuel break, post and pole, and patch cuts which would occur over a total of 598 acres. These activities would also impact approximately 4 additional acres for Temporary Access Routes, Landings, and Skid Trails. All activity areas (Map 2) could have some amount of drop, lop, and scatter activities which could impact slender moonwort as described above. Alternative 2 May Impact slender moonwort individuals or potential habitat, but will not likely contribute to a trend towards federal listing or cause a loss of viability to the population or species. Alternative 3- Impacts of prescribed fire activities and pile burning in Alternative 3 are identical to Alternative 2. Impacts as described above would occur on 1,241 acres with 496 acres being targeted for burning. Slash from thinning activities would be piled and burned resulting in an additional 100 acres impacted by fire.


Alternative 3 would have no pre-commercial thinning, shaded fuel break, no post and pole, and no patch cuts removing potential impacts from 319 acres as compared to Alternative 2. No impacts from Temporary Access Routes, Landings, and Skid Trails would occur in Alternative 3 as these activities would not occur. The hand treatments of Alternative 3 would occur over 1,642 acres verse 1,424 in Alternative 2. The mechanical treatments would be limited to 100 feet from structures and would impact 20 acres. Alternative 3 May Impact slender moonwort individuals or potential habitat, but will not likely contribute to a trend towards federal listing or cause a loss of viability to the population or species.

Simpson’s Hedgehog Cactus (Pediocactus simpsonii) Environmental Consequences Simpson’s Hedgehog cactus is a wide ranging species that can be found in many diverse habitats (i.e. meadows, open forested areas, high elevation cushion plant habitats, and manmade habitats such as road shoulders), there are many areas of potential habitat that exist within the analysis area. No individuals were identified during project surveys, however, the fact that the entire project area was not surveyed and that surveyors could have missed individuals means that unknown individuals could occur in the project area. Burning and soil disturbing activities associated with project activities within the potential habitat could directly kill individuals through burning, crushing, or removal and could alter soil conditions necessary for the existence of this species. These activities could bury or destroy seeds that exist in the soil. Determinations Alternative 1- No Action means that no specific management activities proposed by the Rock Creek Project would occur. Ongoing and permitted uses on National Forest system lands would continue within the project area. Management activities previously approved by other environmental analyses and decision documents would also continue to be implemented. Impacts to Simpson’s hedgehog cactus would continue to exist as they have in the past. The No Action Alternative would have No Impact on Simpson’s hedgehog cactus. Alternative 2- Impacts from prescribed fire could occur across 1,241 acre of the project area (Map 2) and 100 acres to burn piles created from thinning activities (both mechanical and hand). Prescribed fire would not be used in the 545 acre zone marked as fire avoidance due to erosion potential, weed infestation and spread, and ability to control the burn. The burn would be targeting 496 acres of the larger burn area. Given the estimated 10 year time frame for implementation, treatments may need to be modified based upon non-project influenced changes in vegetation conditions (i.e. wildfire, insect or disease epidemic). The acres treated would be adjusted as needed to ensure the overall effects are consistent with the management objectives to move toward desired conditions. Hand treatments would occur over 1,424 acres and would be done by individuals using a chainsaw. Impacts from mechanical treatments would occur in areas identified as such and identified as pre-commercial thinning, shaded fuel break, post and pole, and patch cuts which would occur over a total of 598 acres. These activities would also impact approximately 4


additional acres for Temporary Access Routes, Landings, and Skid Trails. All activity areas (Map 2) could have some amount of drop, lop, and scatter activities which could impact Simpson’s Hedgehog cactus as described above. Alternative 2 May Impact Simpson’s Hedgehog cactus individuals or potential habitat, but will not likely contribute to a trend towards federal listing or cause a loss of viability to the population or species. Alternative 3- Impacts of prescribed fire activities and pile burning in Alternative 3 are identical to Alternative 2. Impacts as described above would occur on 1,241 acres with 496 acres being targeted for burning. Slash from thinning activities would be piled and burned resulting in an additional 100 acres impacted by fire. Alternative 3 would have pre-commercial thinning, no shaded fuel break, no post and pole, and no patch cuts removing potential impacts from 319 acres as compared to Alternative 2. The hand treatments of Alternative 3 would occur over 1,642 acres verse 1,424 in Alternative 2. No impacts from Temporary Access Routes, Landings, and Skid Trails would occur in Alternative 3 as these activities would not occur. The mechanical treatments would be limited to 100 feet from structures and would impact 20 acres. Alternative 3 May Impact Simpson’s Hedgehog cactus individuals or potential habitat, but will not likely contribute to a trend towards federal listing or cause a loss of viability to the population or species. Table 3: Summary of Determinations

REGIONAL FORESTER’S SENSITIVE & FOREST WATCH PLANT SPECIES Species No Action Alternative 2 Alternative 3

Slender Moonwort NI MI MI Simpson’s Hedgehog Cactus NI MI MI

(Key Issue) NON-NATIVE INVASIVE NOXIOUS (WEED) PLANT SPECIES Environmental Consequences Proposed fuel reduction activities would occur in known populations of non-native invasive and noxious plant species. This could stimulate the sprouting of stoloniferous root systems, spread seed with the movement of soil, and create areas of disturbed soil for new colonization by existing and new species. All sites with non-native invasive species have viable seed in the soil and movement of this soil scarifies the seed and aids in germination as well as moving seed to other locations on vehicles, equipment, tools, foot wear, and clothing. Proposed activities could introduce non-native plant species into areas that currently do not have them. Potential indirect effects associated with noxious weeds and non-native invasive plant species infestations may include loss of wildlife habitat and loss of rangeland for grazing due to the diminished native vegetation communities, soil erosion due to shorter-lived annual species invasions, and consequent increased fire susceptibility due to dry dead stands of annual non-native invasive plant species (e.g., cheatgrass stands). If infestations are not eradicated or


contained, noxious weeds or non-native invasive plant species sites would increase, eventually eliminating the native vegetation and replacing the plant regime with an undesirable plant community. Vehicles and equipment leaving the analysis area that have traveled through area infested with noxious weeds or non-native invasive plant species, if not washed prior to leaving, may transport and spread noxious weeds or non-native invasive plant species to other locations. Wildlife and livestock in the area also could transport noxious weeds or non-native invasive plant species seed in their fur and hooves. Birds that have eaten seeds and wind dispersion are additional possible seed vectors. The increase or introduction of non-native plant species could shift the species composition of native plant communities to a less diverse community of non-natives, annuals, or monoculture. The use of chemical herbicides to treat noxious plant species are lethal to most plants killing them along with the targeted non-native species. Chemicals used to treat non-native plants can affect the performance, foraging, and reproduction of plant pollinators and soil microbes associated with many native species eliminating them from the area and changing pollination reproduction and associated soil conditions. Project design criteria and best management practices incorporate features to increase the health of native plant communities and reduce potential for weed introduction and spread; such as fire intensity goals being low to moderate, retaining large diameter seed trees, RCA and noxious and non-native invasive plant species avoidance, ongoing noxious species treatments and monitoring, and prevention measures such as cleaning vehicles and equipment prior to entering the Forest and after they have traveled through or worked in infested areas before moving to an area where no known non-natives exist. Indicator Total acres at risk of introduction and/or spread of noxious and invasive plant species based upon treatment type and susceptibility. Determinations Alternative 1- No Action means no projects would occur within the analysis area. All effects would continue to exist as they have in the past. Within the project area 26% (2,070 acres) would remaim at an elevated risk for weed introduction and spread based on vegetation type, current infestations, and current activities occuring in the area. Fuels would continue to increase over time and contribute to a continued aging and deterioration of vegetation communities increasing the risk of weed spread and invasion as diversity dropped and native communities became less resilient. Ongoing noxious and non-native plant treatment practices would lessen the potential of spreading the existing infestations in the analysis area. Alternative 2- Impacts from prescribed fire could occur across 1,241 acre of the project area (Map 2) and 100 acres to burn piles created from thinning activities (both mechanical and hand). Prescribed fire would not be used in the 545 acre zone (Map 2) marked as fire avoidance due to erosion potential, weed infestation and spread, and ability to control the burn. The burn would be targeting 496 acres of the larger burn area.


Hand treatments and pre-commercial thinning would occur over 1,424 acres and would be done by individuals using a chainsaw. There are 980 acres of aspen and aspen/conifer mix within hand treatment areas that could be burned. Impacts from mechanical treatments would occur in areas identified as such and identified as pre-commercial thinning, shaded fuel break, post and pole, and patch cuts which would occur over a total of 598 acres. These activities would also impact approximately 4 additional acres for Temporary Access Routes, Landings, and Skid Trails. All activity areas (Map 2) could have some amount of drop, lop, and scatter activities. Alternative 2 would create disturbances in native plant communities. Before treatments 2,070 acres of the project area would be at risk of invasion from non-native species. Activities proposed in Alternative 2 would increase the risk of invasion or spread on 2,544 acres. Compliance with project design criteria, mitigation measures and best management practices would reduce the affects that could introduce or spread noxious and invasive plants. Additionally the implementation of ongoing noxious and non-native plant treatment practices would lessen the potential of spreading the existing infestations in the analysis area. This alternative would provide a long term benefit of increased resiliency and fire adapt communities. Alternative 3- Impacts of prescribed fire activities and pile burning in Alternative 3 are identical to Alternative 2. Impacts as described above would occur on 1,241 acres with 496 acres being targeted for burning. Slash from thinning activities would be piled and burned resulting in an additional 100 acres impacted by fire. Alternative 3 would have no pre-commercial thinning, no shaded fuel break, no post and pole, and no patch cuts. The hand treatments of Alternative 3 would occur over 1,642 acres verse 1,424 in Alternative 2. There are 1,185 acres of aspen and aspen/conifer mix within hand treatment areas that could be burned. The mechanical treatments would be limited to 100 feet from structures and would impact 20 acres. Alternative 3 would create disturbances in native plant communities but to a lesser extent than Alternative 2. Before treatments 2,070 acres of the project area would be at risk of invasion from non-native species. Activities proposed in Alternative 3 would increase the risk of invasion or spread on 2,446 acres. Compliance with project design criteria, mitigation measures and best management practices would reduce the affects that could spread noxious and invasive plants. Additionally the implementation of ongoing noxious and non-native plant treatment practices would lessen the potential of spreading the existing infestations in the analysis area.

POLLINATORS Environmental Consequences The Proposed activities such as temporary road construction and decommissioning, tree removal (mechanical and hand), and prescribed fire could affect pollinators directly by destroying the nests of ground nesting species and trample individuals. Vegetation treatments could alter the native plant communities causing species composition shifts and subsequent loss of pollen sources for the native pollinators associated with the community. If other flowering plants are not available, pollinator species could experience a reduction in food availability forcing them to travel further for food making their survival more difficult. This has effects throughout the food chain, as reduced pollination leads to reduced fruit on which birds and other animals depend.


Pollinators may indirectly be affected through the chemical treatments of non-native plant species. While most herbicides don’t directly target pollinators, they do eliminate plants that provide a food source. Unless alternate flowers are available nearby, pollinators nesting in an area are subsequently forced to forage more widely for nectar and pollen, which requires more energy and exposes them to more threats. As a result, they produce fewer offspring to emerge the following year. Many pesticides are acutely toxic to bees and result in death. Carbamates, organophosphates, synthetic pyrethroids, chlorinated cylcodienes and neonicotinoids are highly toxic to bees. Currently none of the herbicides used on the Forest contain these chemicals. Herbicide levels that do not kill pollinators at significant rates may nonetheless have effects on performance that inhibit tasks such as olfactory learning, foraging, and reproduction, which affects hive survival. Poison risk is not restricted to contact with chemicals in the field. Poisonings occur when pollinators contact chemical residue on plants in the hours or days after application. Slow-acting toxins may be carried back to the nest where they are stored with pollen and nectar and later eaten consumed or absorbed. Contaminated pollen can remain toxic for a long time, killing the larvae or, in social species, the other adults in the nest. Also, many solitary pollinator species gather nest-building materials, such as pieces of leaves, mud, plant hairs, or plant resins. If these materials are taken from recently treated plants, they can contaminate the nests. Sub-lethal doses of chemicals can affect the behavior of pollinators. This includes trouble navigating their way back to the nest after foraging, or simply be unable to fly. All of these changes in behavior make foraging and nest building difficult, and ultimately, lead to the premature death of pollinators and their offspring. Determinations Alternative 1- No Action means no projects would occur within the analysis area. All effects would continue to exist as they have in the past. Fuels would continue to increase over time and contribute to a continued aging and deterioration of vegetation communities. This would result in a drop in plant species diversity. This drop in diversity would reduce food and shelter sources for pollinators. Alternative 2 – Impacts from prescribed fire could occur across 1,241 acre of the project area (Map 2) and 100 acres to burn piles created from thinning activities (both mechanical and hand). Prescribed fire would not be used in the 545 acre zone marked as fire avoidance due to erosion potential, weed infestation and spread, and ability to control the burn. The burn would be targeting 496 acres of the larger burn area. Hand treatments and pre-commercial thinning would occur over 1,428 acres and would be done by individuals using a chainsaw. Impacts from mechanical treatments would occur in areas identified as such and identified as pre-commercial thinning, shaded fuel break, post and pole, and patch cuts which would occur over a total of 598 acres. These activities would also impact approximately 4 additional acres for Temporary Access Routes, Landings, and Skid Trails. All activity areas (Map 2) could have some amount of drop, lop, and scatter activities. Alternative 2 would create disturbances in native plant communities and to pollinators due to the proposed vegetation treatments, and ground disturbing activities associated with trails, roads, and facility activities. The Proposed Action may affect native pollinators, and in turn this could affect


the ESA, Sensitive, and Watch plant species that rely on insect pollination. The Proposed Action would create disturbances in native plant communities and to pollinators due to the removal of native vegetation, and ground disturbing activities associated mechanical timber removal activities. Alternative 3- Impacts of prescribed fire activities and pile burning in Alternative 3 are identical to Alternative 2. Impacts as described above would occur on 1,241 acres with 496 acres being targeted for burning. Slash from thinning activities would be piled and burned resulting in an additional 100 acres impacted by fire. Alternative 3 would have no pre-commercial thinning, no shaded fuel break, no post and pole, and no patch cuts. The hand treatments of Alternative 3 would occur over 1,642 acres verse 1,424 in Alternative 2. The mechanical treatments would be limited to 100 feet from structures and would impact 20 acres. Alternative 3 would create disturbances in native plant communities and to pollinators due to the proposed vegetation treatments, and ground disturbing activities associated with trails, roads, and facility activities. The activities may affect native pollinators, and in turn this could affect the Sensitive and Watch plant species that rely on insect pollination. Alternative 3 would create disturbances in native plant communities and to pollinators due to the removal of native vegetation, and ground disturbing activities associated with timber removal activities but to a lesser extent than Alternative 2.

CUMULATIVE EFFECTS The Endangered Species Act (ESA) defines cumulative effects (50 CFR 402.2) as the additive effects of state and private activities that are reasonably certain to occur in the watershed where the Federal Action occurs. Under the ESA, an analysis of cumulative effects on ESA-listed species and their critical habitat is relevant only in determining whether the continued existence of a species would be jeopardized or whether critical habitat would be adversely modified or destroyed. The effects of vegetation treatmants are expected to be long-term (> 15 years). The timeframe effects of implementation actions are expected to be limited to the short-term (3 - 15 years). The National Environmental Policy Act (NEPA) defines cumulative effects as all past, present, and foreseeable future actions within the analysis area. The primary federal activities that have impacted sensitive plant species of concern and their habitats on the Minidoka District of the Sawtooth Forest include construction and use of system and non-system roads, past and present livestock grazing, pesticide and herbicide application, recreation and non-recreation special use permitted activities, developed recreation, water diversion structures, irrigation (inadvertent), current and past timber harvest, current and past mining activity, personal use firewood cutting, and dispersed recreation (including skiing and snowmobiling). Within the project area, the primary federal activities that have impacted the area are timber harvesting and firewood cutting, mining, summer and winter recreation trail uses, dispersed


camping activities, fire suppression, and forest Service Administrative Site activities. Of these act

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