bald mountain projecta123.g.akamai.net/7/123/11558/abc123/forestservic... · 2017-02-13 · meadows...

Environmental Assessment – Appendices Bald Mountain Project

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Appendix E – Bald Mountain Meadows and WIN Sites Detailed Descriptions and Treatment Maps

Table E- 1. Meadows selected for conifer encroachment analysis in the Bald Mountain Project area. ..............1

Figure E- 1. Display of proposed treatments for meadow 517M100. 3






Meadows Analyzed and Maps of Proposed Treatments

The aerial photo analyses of conifer encroachment in the Bald Mountain Project area (Platt & Gallegos 2013, Project record) yielded eight meadows for further field assessment. Four meadows were rated as having severe encroachment, class 6 (36-60% encroachment), two were rated as having extensive encroachment, class 5 (16-35% encroachment), and two were rated as having moderate encroachment, class 4 (6-15% encroachment). These meadows were originally chosen due to their relatively large areas and the presence of large distinct lobes of conifer encroachment. These meadows were assessed in the field using the protocol originally developed by MacDonald and Kuitu. See Table E-1 below for a list of meadows selected for field assessment and analysis data gathered from the aerial photo analyses. Following the table is detailed descriptions of the meadows proposed for treatments along with maps of the treatments.

Table E- 1. Meadows selected for conifer encroachment analysis in the Bald Mountain Project area.

Bald Mountain Meadow Conifer Encroachment

Meadow Number Meadow Name Current

Acres

1940

Acres

Meadow Acre

Change

Percent

Change Class

517M100 Poison 10.15 19.97 -9.82 49.17 6

517M15 Grade 1 14.55 26.96 -12.41 46.03 6

517M20/517M17 Markwood/Poison 69.51 79.49 -3.37 12.55 4

520M213 No Name 4.76 7.59 -2.84 37.36 6

520M214 No Name 7.28 8.42 -1.14 13.58 4

520M233 No Name 8.94 14.77 -5.83 39.49 6

520M247 No Name 5.92 6.97 -1.05 15.08 5

517M100 (Poison Meadow)

Poison Meadow (517M100) is located along Dinkey Creek Road at an elevation of 5,730 feet in the lower montane. The meadow is 10.15 acres in size and consists of four main parts; 1) a central, wide body, 2) a western arm, 3) a northern arm and 4) a highly encroached eastern arm. The meadow is saturated


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throughout, and contains a perennial stream. The stream is likely the main source of the water in the meadow and is mapped as a riparian low gradient hydrogeomorphic type.

Evidence of light to moderate grazing was observed, with no evidence of trampled or bare soil. Evidence of historic moderate to extensive logging is evident adjacent to and within the meadow, and a total of 26 cut and rotting stumps are present within the meadow or on the margins. At least 11 logs were felled into and left within the meadow. Fire scars on stumps are common in the surrounding forest. Fire scars on living trees were not observed.

An incised channel, locally two meters deep, and four knickpoints were observed in the northern arm of the meadow. The knickpoints have been successfully arrested with in-stream structures consisting of rocks and filter fabric. Dinkey Creek Road crosses the meadow between the main body and the northern arm. Lobes of sediment originating from the road and adjacent unpaved turnouts are present in the meadow immediately south of the road. The culvert beneath Dinkey Creek Road is likely placed too high, and a small drop and deep plunge pool have developed on the downstream side of the culvert. A highly incised channel is present in the encroached east arm of the meadow. An old road prism crosses the main body of the meadow, causing ponding upstream.

Most of the encroachment in Poison Meadow is located in the section of the east arm closest to the main body of the meadow and in tree islands throughout the meadow. In total, approximately 324 small conifers (<2m) and 223 large conifers (>2m) composed predominately of incense cedar, white fir, and ponderosa pine appear to be encroaching into the meadow. See Figure E-1 for a display of the meadow and the proposed treatments within and adjacent to the meadow.


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Figure E- 1. Display of proposed treatments for meadow 517M100.

517M15 (Grade 1 Meadow)

Grade 1 Meadow (517M15) is located along Dinkey Creek Road at an elevation of 5,820 feet in the lower montane. The meadow is approximately 14.55 acres in size, and consists of two main parts: 1) a lower, wide body and 2) a long, riparian arm. Conifer encroachment is concentrated along the southern margins of the main body, and within the riparian arm. The meadow contains both riparian and herbaceous vegetation. The majority of the meadow is mapped as a riparian low gradient hydrogeomorphic type. A small lobe north of the riparian arm and the north end of the main body are mapped as a dry hydrogeomorphic type.

Evidence of light to moderate grazing was observed, with less than five percent of the meadow trampled. Evidence of historic moderate to extensive logging was observed in the surrounding forest, and 25 cut stumps were found within the meadow. The only evidence of fire observed were fire scars on decomposing stumps in the adjacent forest. A knickpoint approximately 2.5 feet tall is present west of treatment area 5. An incised channel is present throughout approximately 40 percent of the meadow. Dinkey Creek Road and road 10S06 cross the main body of the meadow. Additionally, an OHV trail crosses the narrow arm of the meadow between treatment areas 6 and 7. Sediment from this OHV trail is being transported and deposited just downstream. An old wooden fence is present in the meadow. Additionally, several logs have been placed and arranged near the wood fence to form a continuous surface.

Approximately 90 small conifers consisting predominately of ponderosa pine were found growing on the meadow fringes north of Dinkey Creek Road. These conifers were found to be growing on elevated, terrace-like features above the main lobe of the meadow. Many of the stumps documented are located in this area. Most of the areas mapped as encroached south of Dinkey Creek Road are occupied by riparian vegetation, with conifer tree islands locally growing within the dense riparian vegetation. In total, approximately 180 small conifers (<2m) and 160 large conifers (>2m) are encroaching within the meadow south of Dinkey Creek Road. See Figure E-2 for a display of the meadow and the proposed treatments within and adjacent to the meadow.


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Markwood/Poison Meadow (517M20/517M17)

Markwood Meadow is located along Dinkey Creek Road at an elevation of 6,000 feet in the lower montane. For the purpose of this study, Markwood Meadow refers to two meadows; 517M20 and 517M17. Originally designated as two separate meadows, the aerial analysis revealed that they are actually a single, connected meadow. This was later confirmed during the field assessment. Markwood Meadow is approximately 69.51 acres in size and consists of two main parts: 1) a large, main body, and 2) a narrow riparian arm. Most of the encroachment is concentrated along the western arm of the meadow; the main body of the meadow has actually expanded since 1944. Due to the expansion of the main body of the meadow, this area was removed from the study, and the field assessment focused on the encroached, western arm.

A perennial stream flows through the west arm of Markwood Meadow. As such, the arm is predominately a riparian low gradient hydrogeomorphic type. A small, highly encroached lobe of the meadow off the western arm occurs on hillside that is concave across slope. It’s likely that the source of the water in this lobe is a spring upslope, and the area is mapped as a discharge slope hydrogeomorphic type. Northeast of this location, a small lobe of the meadow is mapped as a dry hydrogeomorphic type.

Evidence of light grazing was observed in Markwood Meadow. Evidence of moderate historical logging was observed in the forest adjacent to the meadow, and seven cut stumps were found within the west arm of the meadow. Fire scars were observed on stumps and on very large trees adjacent to the meadow. Dinkey Creek Road crosses the meadow, and the culvert beneath the road is likely placed too high on the downstream end, where a small drop and very large plunge pool have developed. Two knickpoints roughly 40 to 60cm tall and an incised channel of up to one meter are located in the meadow as well. The meadow immediately downstream of the knickpoints is significantly drier than above the knickpoints. In total, approximately 95 conifers are encroaching along the margins and within Markwood Meadow. See Figures E-3 and E-4 for a display of the meadow and the proposed treatments within and adjacent to the meadow.


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520M233

Meadow 520M233 is located along road 09S010, approximately one half of a mile south of the intersection with road 09S062, with a lower elevation of 8,100 feet and an upper elevation of 8,400 feet, in the upper montane. The meadow is a headwater hill slope meadow, is 8.94 acres in size and consists of two main parts; 1) an open lobe and encroached arm below and west of road 09S010, and 2) an upper area consisting of three open lobes and several areas mapped as encroached during the aerial analysis. No perennial streams enter at the head of the meadow, and numerous seeps and springs were observed within the meadow. As such, the meadow is mapped as a discharge slope hydrogeomorphic type. The topography of the meadow is highly varied, and stepped profiles consisting of boulder, steep faces and gravelly to cobbly flat surfaces are common. The predominate geology mapped for the area is glacial moraines and till, so it’s likely that the stepped profiles are associated with ground or recessional moraines.

Evidence of light grazing was observed within meadow 520M233. Evidence of historic extensive logging is present adjacent to the meadow, and evidence of more recent moderate to extensive logging was observed north of the western lobe of the meadow, below road 09S010. Very little evidence of fire was observed; fire scars were found on several decomposing stumps in the forest south of the meadow.


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An old road prism crosses the lower portion of the west lobe of the meadow, below road 09S010. An undersized, failed culvert is present where the road formerly crossed the creek within this portion of the meadow. At some time after the culvert failed, it was replaced with a poorly rocked crossing. Upstream from this crossing, the stream is incised approximately 40cm. Road 09S010 crosses the meadow, and a large cut slope was created in the meadow to accommodate the road. Subsurface flow from the meadow is confined into a roadside ditch and culvert at this location. A knickpoint is also present at this location, adjacent to the road. Spring morphology similar to those of springs upslope is present immediately above the road cut; however, the area is completely dry, and many small (<2m) conifers are encroaching here.

The field assessment revealed that conifer encroachment is spread throughout the meadow, with many areas originally mapped as open meadow during the aerial analysis actually occupied by relatively small conifers under four meters in height. Only four areas of open meadow remain, but meadow vegetation was found throughout the areas mapped as encroached during the aerial analysis. In total, approximately 200 small conifers (<2m) and 200 large conifers (>2m) consisting predominately of lodgepole pine and red fir are encroaching into the meadow. However, due to line of sight issues and difficulties pinpointing precise locations on the map, this is a conservative estimate, and it’s likely that the actual number of encroaching conifers is far greater. See Figure E-5 for a display of the meadow and the proposed treatments within and adjacent to the meadow.



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520M247

Meadow 520M247 is located off road 09S491, approximately one quarter of a mile from the junction of roads 09S010 and 09S009 at an elevation of 7,500 feet in the upper montane. The meadow is a headwater hill slope meadow, is 5.92 acres in size and consists of three main parts: 1) a large, main body, 2) a narrow, riparian arm below the main body, and 3) a smaller detached lobe and riparian arm above road 09S491. The soil transect was placed so that it passed through areas mapped as encroached during the aerial analysis. The majority of the meadow is wet, and many springs and seeps are present. As such, the main body and the detached lobe are mapped as discharge slope hydrogeomorphic types. Water from the main body of the meadow flows into the lower arm; however, only a high flow channel is present in the lower arm of the meadow, but a perennial channel exists below the meadow. This information meets the criteria for a subsurface low gradient hydrogeomorphic type, and the lower arm was mapped as such. Most of the areas mapped as encroached are located in the narrow arm below the main body, in the narrow arm of the detached lobe, and in tree islands within the main body of the meadow.

Six knickpoints were discovered within meadow 520M247. The heights of these knickpoints ranged from 1.5 to 3 feet in height. It wasn’t immediately clear what led to their formation; however, the culvert beneath road 09S010 may have been placed too low.

During the field assessment, approximately 200 small (<2m) conifers and 125 large conifers (>2m) were observed growing within the meadow. While several small conifers were observed growing within areas mapped as open meadow, the field survey is largely consistent with the aerial analysis, and it is recommended that conifers between 1 and 12 inches in diameter be cut or felled. The treatment area is approximately 3.02 acres. Additionally, the meadow buffer on the east side of meadow 520M247 should be thinned, and fire should be introduced to maintain meadow boundaries. The area can easily be accessed by road 09S491. See Figure E-5 for a display of the meadow and the proposed treatments within and adjacent to the meadow.


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WIN Sites Detailed Treatment Descriptions

This section describes WIN sites and proposed treatments in more detail.

53032A and B – These sites are located in 517M9, in meadow 517.0054. Treatments would be implemented concurrent with or as soon as possible after the thinning in Plan ID 1123, because access would require the use of project temp roads and skid trails.

53032A is a site of bank erosion that was first documented in 1990. A field visit in 2012 found that the area was about 80% vegetated and appeared stable, making it a low priority for treatment. However, because 53032B was identified for treatment in the same meadow area, both sites could be treated. If the bank


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erosion site (A) is not on a clear trend towards recovery, the steep top of bank would be laid back to a more stable angle. The upper bank would be protected with coir netting, which would provide groundcover and microsites for natural seed germination. Based on similar work at Snow Corral Meadow, natural plant growth is expected to occur.

53032B is a headcut located in the forest near the meadow in an ephemeral tributary to the meadow channel. The headcut would be reshaped to a more stable angle. Any soil removed would be scattered in the adjacent forest, where it would not be transported into the meadow or any stream channel. The reshaped channel would be armored with rock to create a ‘rock run-down’ structure (Zeedyk and Van Clothier 2009). Rock is not available on-site and would be brought in from the nearest road using a power wheelbarrow. This would not require entering the meadow with the equipment. Protection from livestock would not be needed, and no fencing or barriers are proposed.

53036 – This WIN site in 517.1003 is located adjacent to road 9S14, which provides good access for the work. It is mostly noted for plugging a stream crossing culvert on road 9S14, causing water to flow over the road and erode the fill. The source of the sediment that continually plugs this culvert is two gullies that originate on a disturbed, sandy slope just upstream of the culvert. The gullies appear to receive concentrated runoff from an old skid trail higher on that slope. The stream crossing would be repaired as part of the project road work. WIN treatments would focus on gully and hillslope stabilization, and dispersal of water from the skid trail. Heavy equipment would be used to improve drainage on the skid trail, which is not in a treatment area and would not be used for other proposed treatments. After drainage improvements have been made, slope and gully treatments would be implemented. (Slope and gully stabilization are not likely to succeed if concentrated flow from the skid trail is not effectively dissipated.) The goal at this WIN site would be to increase groundcover for erosion control. A combination of rock and native material groundcover would be used, as site-specific conditions allow. Rather than cutting sparse vegetation at the site, slash may be transported from nearby treatment areas to be spread by hand on portions of the slope that are lacking groundcover. Work at this WIN site is expected to require annual monitoring and periodic maintenance/adjustments.

53047 – This site is located in 517.0006, at the downstream end of 517M2. It documents a large headcut and downstream bank erosion. The site was repaired in 1996 with erosion fabric and willow plantings, but monitoring in 1997 indicated that cattle had trampled the repair, ripped the fabric and eaten the plantings. There are no records of any subsequent work. The proposed repair for this site includes headcut stabilization, bank erosion control, and protection from cattle trampling. Timing should be prior to or in the same summer as the adjacent stand treatments, so that the site is stabilized prior to modification of the surrounding and upstream watershed. A ‘Zuni Bowl’ and rock sill (Zeedyk and Clothier 2009) would be constructed to stabilize the headcut and provide grade control. Stream diversion would not be needed because in most years the site does not have flowing water in the late summer, although there is a persistent scour pool below the headcut. Some overhanging woody vegetation would need to be cut back to provide access and mobility for worker safety. Willow plantings (stakes) would be used along edges of the Zuni Bowl and on the downstream banks. Banks appear to have made progress towards recovery, but continued cattle trampling has occurred where animals access the pool for water. Worker access to the site would require clearing of an old road bed, or, if work is done concurrent with stand treatments, could follow access developed for the stand treatments. There is some rock on site from previous repairs, but additional rock would need to be moved in, likely requiring power wheelbarrows for the final approach. We expect that the stand treatments would facilitate better livestock movement and hopefully reduce concentrated trailing. The Range specialist would coordinate with the TSA and Fuels specialist to determine whether existing or activity-generated material could be left near the site as a barrier. If this is not feasible or is found not to be effective, a small exclosure would be constructed using t-posts and rigid ‘hog wire’ fence panels to protect the site. The fence would be approximately 160 feet in length. The wire panels would be taken down


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after cows are off the allotment in the fall and put up prior to their arrival each spring, until the repair is stable and vegetation is established (approximately 5 years).

53048A and B – These sites document headcuts and bank erosion in 517M1, in 523.3101 (the meadow crosses the subdrainage boundary and its number matches the other subdrainage). The sites were repaired by armoring them with filter fabric and rock in 1996, and maintained in 2006. Although they are currently stable, they are included in the proposed action in case of future maintenance needs. Prior to or concurrent with vegetation treatments in the surrounding stands, these sites would be inspected and any noted maintenance needs would be corrected so that the sites are fully capable of withstanding any potential increases in post-project stream flow (though increases are not predicted by the analysis). Needed maintenance would consist of repair of the existing rock bank armoring and headcut structure, accomplished using hand work and on-site rock materials.

53244 – This site documents multiple headcuts in lower Markwood Meadow (517M20, in 517.0008). The site proposed for treatment is in the vicinity of the previously documented headcuts, but this specific problem was not previously documented. High flows fill this channel and access the floodplain (the meadow surface). This is the desired condition and helps to dissipate stream energy across a large area. However, because of a natural constriction between a rock outcrop and a willow clump, flow inside the channel is reduced in a short section, causing there to be a short section where the channel is not entirely full. Water from the meadow surface has flowed back into this section of channel, dropping over the channel bank and causing some scour of the upper bank. If left unchecked, this could eventually scour a new, straight channel segment and form a meander cut-off. This would release sediment and reduce the channel sinuosity, which are both undesired outcomes. Vegetation at the site is low in deep-rooted sod forming species. The proposed treatment would leave the willow clump in place because it provides many benefits (stabilizes soil, provides shade and habitat complexity), and would armor the section of bank where flood flows are dropping back into the channel, to prevent formation of a migrating knickpoint that could evolve into a meander cut-off. This would be accomplished using filter fabric and rock, installed by hand. The site is near 9S05 and is small (<4 feet of bank would be treated), so materials would be carried in. No wheeled or mechanized equipment would be used, but vegetation trampling would result from multiple trips being made to the site and workers congregating at the site. Vegetation (local site seed and willow stakes) would also be utilized to stabilize and naturalize the rock work and surrounding area.

New Site – This site is a medium-sized headcut in Markwood Creek in 517M17. Initial evaluation determined that it did not appear active, and it was characterized as low priority for treatment. However, based on the amount of proposed treatment in the upstream subdrainage (517.0008), the reduction in BA, and increase in %ERAs to over 13%, it is proposed for stabilization to ensure that it will be capable of withstanding any increases in streamflow that may occur as a result of the proposed vegetation treatments. The site would be stabilized by constructing a ‘Zuni Bowl’ (Zeedyk and Clothier 2009) with rock large enough to remain immobile in this channel. Because it is a perennial stream, flow would be diverted around the work site, which would affect an estimated 40 feet of stream channel for up to 10 days. A power wheelbarrow would be used to transport rock from Dinkey Creek Road to the site. The headcut would be reshaped to create the proper foundation for rock placement, and rocks would be keyed into the banks. A rock sill would be installed just downstream of the Zuni Bowl to provide additional energy dissipation and grade control.

54026 – This WIN site consists of a series of headcuts in a perennial channel in 520M247 (subdrainage 520.6051). This channel is a tributary to Cow Creek, but does not flow into the reach occupied by LCT. Each knickpoint that is determined to be unstable would be stabilized with a Zuni Bowl structure, and a rock sill would be constructed just downstream to provide grade control. One of the headcuts is large (3.5 feet tall and 35 feet wide). The large headcut area would be protected from cattle trampling with a temporary fence constructed with t-posts and rigid ‘hog wire’ panels (the smaller sites should not require protection). The fence panels would be removed each fall after livestock are gathered from the allotment, and raised each


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spring prior to livestock being turned out. The area would be monitored, and if undesirable effects are found, such as trampling of unfenced sites or erosion caused by livestock trailing along the fence, the fencing would be adjusted. Road 9S941 provides good access to this location. A power wheelbarrow would be used to bring rock from the road to the work sites. The stream is spring-fed and is perennial, so flow would need to be diverted around work areas. This would dewater approximately 20 – 30 feet of channel at each headcut that is stabilized, for up to 5 days at each small knickpoint and up to 10 days at the large site.

54047 – This WIN site documents multiple headcuts in channels near the base of 520M249, in 520.5002. The channel is a tributary to the reach of Rock Creek that is occupied by SYLF. Headcuts in 520M248, downstream, have been successfully repaired, but there is no evidence that this site has ever been treated. Access would utilize an existing ‘unauthorized route’ (KD-44) off of 9S09. A power wheelbarrow would be needed to transport rock to the site, which would be used to construct Zuni Bowls on two smaller headcuts and a two to three tier step pool structure (Zeedyk and Clothier 2009) on the largest. Each structure would have a rock sill constructed downstream to provide grade control. The main channel, where the largest headcut is located, is perennial and would likely diversion of flow around the work site. This would dewater approximately 40 feet of channel for up to 10 days. The repaired sites would be protected with temporary fence constructed of t-posts and rigid ‘hog wire’ panels, which would be raised each spring prior to arrival of cattle and taken down each fall after cattle have been gathered from the allotment.

54260 / 54308 – These WIN sites document hillslope and gully erosion in 520.6001 (West Fork Cow Creek). This area was subjected to type conversion treatments including clearcutting, tractor piling, and possibly ripping. The plantation that was created was unsuccessful, even with irrigation, due to damage sustained by the soil. This area displays substantial recovery since the WIN site was initially documented; however, erosion continues, and sediment is delivered to West Fork Cow Creek. In order to protect and improve habitat conditions for the LCT, erosion control treatments would be implemented. Timing would be after the mechanical stand treatments so that erosion control measures are not damaged during those treatments. Techniques would include spreading slash or other on-site native materials to increase groundcover; modifying flow paths to prevent water from accumulating in the gullies; and spot revegetation using on-site seed and jute netting, if necessary. Old burn and ‘cull’ pile remnants would not be disturbed in order to protect potentially occupied YT terrestrial habitat.

54368 – This WIN site documents numerous knickpoints in a small meadow near Exchequer Creek (520.0015). The meadow is partially on private land, and two private cabins are located at its edge. Treatments would consist of construction of ‘Zuni Bowls’ with rock sills for grade control. Rock would need to be transported to the knickpoints. The rock sizes needed here are small enough to manage in a standard wheelbarrow, so the power wheelbarrow would not be necessary. The timing of these treatments would be prior to or concurrent with the adjacent and upstream stand treatments, and the work would be coordinated with the owners of the cabins.

54376 – This site documents erosion caused by an existing landing that was constructed in an ephemeral drainage. The channel flows across the center of the landing, where it has scoured a small channel. Where it flows off the edge of the landing fill, additional erosion is occurring. The drainage pattern here and in the surrounding area is broken and discontinuous, but it appears that sediment has been delivered to Reese Creek. This site is not located in a proposed treatment unit and is not likely to be utilized for vegetation treatments, but it is near Plan ID 139 / 140. Heavy equipment would be needed to remove landing fill from the ephemeral stream channel, which is the material forming the headcut. Road 10S36G is closed and not driveable beyond the landing, so the portion of the landing beyond the channel would be rehabilitated to discourage motor vehicles from driving across the channel. The surface would be ripped and slash material would be incorporated for groundcover and soil improvement. Following the heavy equipment work, the shape of the channel would be fine-tuned using hand work to match the upstream and downstream channel dimensions as closely as possible.

bald mountain projecta123.g.akamai.net/7/123/11558/abc123/forestservic... · 2017-02-13 · meadows...

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