ROCK CREEK FUELS AND VEGETATION PROJECT FORESTED VEGETATION ANALYSIS Karl Fuelling 9/18/2015

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1 ROCK CREEK FUELS AND VEGETATION PROJECT FORESTED VEGETATION ANALYSIS Karl Fuelling 9/18/2015 CURRENT CONDITIONS The vegetation analysis for the Rock Creek project has been done using Arcmap with Vegetation, Classification, Mapping, and Quantitative Inventory (VCMQ) veg data. The current vegetation types by acres are shown in the table below: Vegetation Type Acres Aspen Aspen most abundant tree species, conifers less than 10% 1407 canopy cover Aspen/Conifer Aspen most abundant tree species, conifers at least % canopy cover Conifer/Aspen Conifers most abundant tree species, aspen at least % canopy cover Lodgepole Pine Lodgepole pine most abundant tree species, aspen 777 less than 10% canopy cover Subalpine Fir Subalpine fir most abundant tree species, other 429 conifer species less than 10% canopy cover Dwarf Sagebrush 144 Mountain Big Sagebrush 1232 Forest Shrubland 761 Mountain Shrubland 1181 Grassland 35 Riparian Shrubland and Deciduous 42 Developed 65 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

2 found on 166 acres. This PVG is also not believed to occur in the analysis area. PVG 10 (persistant lodgepole pine) covers 4,523 acres. The current condition in the analysis area for PVG 10 was derived from VCMQ data and is shown in the table below: Tree Size PVG 10 Acres/% G-F/S/S < 4.5 0/0% tall Saplings 0.1-0/0% 4.9 DBH* Small /71% 11.9 DBH Medium /29% 19.9 DBH Large >20 DBH Total 4523 Large tree size not modeled as part of HRV** *DBH Diameter at Breast Height (4.5 from the ground) **HRV Historical Range of Variability The project area does not fit neatly into the PVG 10 description in the Forest Plan. PVG 7 (warm, dry subalpine fir) is the other PVG which the forested stands in the project area could be identified as. However, a key component of PVG 7 is Douglas-fir, which does not occur in the project area. The current acres of aspen do not fit the Forest Plan description for either PVG 7 or 10. Aspen currently makes up 59% of the forested acres in the project area. The desired condition in the Forest Plan calls for only a trace of aspen in PVG 10 and 6-11% in PVG 7. Because Douglas-fir does not occur in the project area the ability to manage for the large tree size class is greatly diminished. Lodgepole pine rarely grows to 20 DBH. Subalpine fir trees over 20 DBH are not common and usually have root rot and fir broom rust which weakens the trees and makes them susceptible to windthrow and breakage. For these reasons PVG 10 is being used to determine the desired condition for tree size in the project area. Most of the subalpine fir is infected with fir broom rust. This disease weakens the trees and slows their growth. Dwarf mistletoe is found in many of the medium sized lodgepole pine. The 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. The mountain pine beetle is at endemic (low) levels with most of the

3 activity in the southern portion of the project area around Porcupine Campground and some of the organization camps. DESIRED CONDITIONS The desired condition for PVG 10 is shown in the table below: Tree Size PVG 10 G-F/S/S 16-23% Saplings 11-16% Small 46-48% Medium 11-20% ENVIRONMENTAL CONSEQUENCES No Action Alternative Changes will occur more slowly to the tree size classes than under either Action Alternative. Trees will not move into the medium tree size class until 2085 in the precommercial thinning (PCT) stands. Trees will not move into the medium tree size class until 2075 in the post and pole (P & P) stands. No timber volume will be produced. Current vegetation conditions will not change in the short term. Aspen stands will decline as conifers grow and shade out the aspens in the long term. Insect and disease levels will slowly spread as stands become denser. Mountain pine beetle activity may increase in those areas not thinned in the PCT, P & P and mechanical treatments. This is because tree density will continue to increase and individual tree vigor will decrease making the trees more susceptible to an attack from the beetle. No Action Acres and Percentages - Precommercial Thinning Stands G-F/S/S 0/0% 0/0% 0/0% 0/0% 0/0% Saplings 251/90% 195/70% 139/50% 84/30% 84/30% Small 28/10% 84/30% 140/50% 195/70% 167/60% Medium 0/0% 0/0% 0/0% 0/0% 28/10% Total

4 Images of the precommercial thinning stands with no treatment are shown below:

5 No Action Acres and Percentages Post and Pole Treatments G-F/S/S 0/0% 0/0% 0/0% 0/0% 0/0% Saplings 5/10% 0/0% 0/0% 0/00% 0/0% Small 50/90% 55/100% 55/100% 50/90% 50/90% Medium 0/0% 0/0% 0/0% 5/10% 5/10% Total

6 Images of the post and pole stands with no treatment are shown below:

7 Alternative 2 The analysis was based on stand exam data collected in the spring of 2015 and the Forest Vegetation Simulator model. The hand treatments in the aspen stands will maintain those stands by removing encroaching conifers and encouraging aspen sprouting by opening up the stands. The hand treatments in the conifer stands will remove ladder fuels and will maintain those stands as conifer stands. Treatments in both veg types will increase tree vigor. The prescribed fire will result in stands being moved back to an earlier successional stage. Aspen sprouting will increase due to both aspen and conifers being killed by the fire. The fire will reduce the amount of fir broom rust in the subalpine fir and dwarf mistletoe in the lodgepole pine in the project area. Timber volume produced from the treatments will be approximately 4 MBF (thousand board feet) per acre in the post and pole harvested acres and 10 MBF per acre in the patch cut harvested acres. The total volume will be approximately 340 MBF. A patch cut will be done on 12 acres. The patch cut will remove all trees over 7 in diameter except those needed to meet snag requirements discussed in the project design features. The 12 acres will be naturally regenerated with lodgepole pine. The tops of the harvested trees will be left in the stand to ensure an adequate number of cones are left to regenerate the stand. This treatment will move the 12 acre stand from the medium size class to the grass/forb/shrub stage.

8 Precommercial thinning will occur on 279 acres. Post and pole harvesting will occur on 55 acres. Both of these treatments will be thinned to a spacing of approximately 11 x 11 feet. This will leave between 300 and 400 trees per acre. The 334 acres PCT and P & P treatment plus the 238 acres of mechanical treatment will have a reduced risk of attack from mountain pine beetle compared to the no action alternative. This is due to the stands having increased vigor which allows the trees to better defend themselves from the beetle by pushing the beetles out of the tree with pitch. Alternative 2 Acres and Percentages - Precommercial Thinning Treatments G-F/S/S 0/0% 0/0% 0/0% 0/0% 0/0% Saplings 251/90% 139/50% 84/30% 84/30% 84/30% Small 28/10% 140/50% 167/60% 111/40% 56/20% Medium 0/0% 0/0% 28/10% 84/30% 139/50% Total Images of the precommercial thinning treatment are shown below:

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11 Alternative 2 Acres and Percentages Post and Pole Treatments G-F/S/S 0/0% 0/0% 0/0% 0/0% 0/0% Saplings 5/10% 0/0% 0/0% 0/0% 0/0% Small 50/90% 55/100% 50/90% 38/70% 38/70% Medium 0/0% 0/0% 5/10% 17/30% 17/30% Total Images of the post and pole treatment are shown below:

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13 The PCT and P & P treatment will not change the size classes immediately because treatments will only thin from below, leaving the larger trees in the stand. Over time the trees that are left will grow more quickly than the No Action Alternative and will reach the medium tree size class sooner. This is reflected in the table below.

14 The vegetation types after treatment are shown in the table below: Vegetation Type Acres Aspen Aspen most abundant tree species, conifers less than 10% 1627 canopy cover Aspen/Conifer Aspen most abundant tree species, conifers at least % canopy cover Conifer/Aspen Conifers most abundant tree species, aspen at least % canopy cover Lodgepole Pine Lodgepole pine most abundant tree species, aspen 777 less than 10% canopy cover Subalpine Fir Subalpine fir most abundant tree species, other 335 conifer species less than 10% canopy cover Dwarf Sagebrush 144 Mountain Big Sagebrush 1232 Forest Shrubland 761 Mountain Shrubland 1181 Grassland 35 Riparian Shrubland and Deciduous 42 Developed 65 The change in acres among vegetation types is due to the prescribed fire treatment.

15 The projected tree size class in PVG 10 in 2025 is shown below. The numbers in the table are based on the patch cut treatment and the prescribed burn. Tree Size PVG 10 Acres/% G-F/S/S < 4.5 tall Saplings DBH* Small DBH Medium DBH 12/<1% 396/9% Total /65% 1182/26% Alternative 3 The precommercial thinning and post and pole treatments will not be done. Therefore, trees will not move into the medium tree size class until 2085 in the precommercial thinning stands and trees will not move into the medium tree size class until 2075 in the post and pole stands. No timber volume will be produced. The hand treatments in the aspen stands will maintain those stands by removing encroaching conifers and encouraging aspen sprouting by opening up the stands. The hand treatments in the conifer stands will remove ladder fuels and will maintain those stands as conifer stands. Treatments in both veg types will increase tree vigor. The prescribed fire will result in stands being moved back to an earlier successional stage. Aspen sprouting will increase due to both aspen and conifers being killed by the fire. The fire will reduce the amount of fir broom rust in the subalpine fir and dwarf mistletoe in the lodgepole pine in the project area. The 20 acres of mechanical treatment will have a reduced risk of attack from mountain pine beetle compared to the no action alternative. This is due to the stands having increased vigor which allows the trees to better defend themselves from the beetle by pushing the beetles out of the tree with pitch. The vegetation types after treatment will be the same as in Alternative 2.

16 The projected tree size class in PVG 10 in 2025 is shown below. The numbers in the table are based on the prescribed burn. Tree Size PVG 10 Acres/% G-F/S/S < 4.5 0/0% tall Saplings /9% 4.9 DBH* Small /65% DBH Medium /26% 19.9 DBH Total 4523 Comparison of All Alternatives No Action Alternative Alternative 2 Alternative 3 Year when medium size class is reached - PCT Year when medium size class is reached - P & P Volume Produced MBF 0 Acres Thinned (PCT/P & P) Acres Patchcut Acres of Medium Tree Size Class Acres with Increased Resistance to Mountain Pine Beetle Hand Treatemnt Acres with Increased Tree Vigor

17 Alternative 2 best meets the purpose and need by increasing the resistance to mountain pine beetle on the most acres. It also will have trees on 334 acres reach the medium size class years sooner than either the No-Action Alternative or Alternative 3. CUMULATIVE EFFECTS The National Environmental Policy Act (NEPA) defines cumulative effects as all past, present, and foreseeable future actions within the analysis area. The Analysis Area is defined as all areas to be affected directly or indirectly by the Federal action and not merely the immediate area involved in the action (50 CFR ). The effects of vegetation treatments are expected to be long-term (> 15 years). The timeframe effects of implementation actions are expected to be limited to the short-term (3-10 years). The primary activities that have impacted forested vegetation within the project area include construction and use of system and non-system roads, past and present livestock grazing, developed recreation, past timber harvest, personal use firewood cutting, personal use Christmas tree cutting and dispersed recreation (including skiing and snowmobiling). Reasonably foreseeable actions include the above listed uses including recreation at or near similar use levels, continued livestock grazing at or near current levels, wildfire suppression, travel management actions including rehabilitation of non-system routes. The addition of new recreational facilities such as parking lots, replacement of ski lifts and slight expansion of current facilities will likely occur to a slight degree as the demand for recreational use of the Rock Creek area is expected to remain high. Approximately 300 acres have been pre-commercially thinned in the project area since Approximately 950 acres have been clearcut in the project area. A small number of clearcuts were done in the 1950 s and 1960 s. Most clearcuts date from the mid 70 s through acres received a seed-tree harvest where enough trees are left to provide a seed source to regenerate the area. These treatments were done from 1975 through A salvage treatment was done around Diamondfield Jack in the 2005, capturing dwarf mistletoe infected trees on 47 acres. Eight acres were salvage harvested in the Eagle Springs fire area in Twenty-one acres were dropped/lopped and prescribed burned in 2007 to promote aspen regeneration. Three wildfires have occurred in the project area since Approximately 265 acres of the precommercial thinning treatment and 16 acres of the post and pole treatment in Alternative 2 will be done in these wildfire areas.

18 The current vegetation types and stand conditions reflect all past treatments. After this project is completed no future vegetation treatments are planned in the Rock Creek drainage.

19 APPENDICES Appendix A No action PCT Stand Appendix B No action P & P Stand Appendix C Alternative 2 PCT Stand Appendix D Alternative 2 P & P Stand CITATIONS 2014 Aerial Insect & Disease Detection Surveys