The Carlton Ridge Research Natural Area (RNA) is an ecologically unique area established in 1988 on the Lolo National Forest because of its unusually extensive community of alpine larch (Larix lyallii) on well-developed soils. While the RNA is generally limited to one section (# 24 of T11N-R21W), Friends of Lolo Peak supports proposals to expand its boundaries to the immediate west (Section 23) and beyond to better encompass the unique combination of topography, soils, and vegetation.
Post Fire Revegetation Studies
1. Members from the Friends of Lolo Peak are participating in useful citizen science efforts at Carlton Ridge RNA. One of our efforts has been in partnership with staff from the USDA Forest Service Region 1, Lolo National Forest, and Rocky Mountain Research Station on studies and research that have ecological and managerial benefit. This project will monitor regrowth and revegetation in the RNA in the aftermath of the Lolo Fire which burned nearly 54,000 acres July through September of 2017. Knowledge of these vegetation trends will be valuable for assessment of the Lolo Fire, as well as future mixed-severity fires in these upper timberline, subalpine forest types in the region.
OTHER EXAMPLES OF IMPORTANT ECOLOGICAL INFORMATION*
2. An important ecological feature of the Carlton Lake basin is the “Krummholz Saddle” on the south edge of the Carlton Creek watershed at about 8560’, southwest of Carlton Lake, where a wind funnel has created a krummholz community of three-foot high shrub-like white bark pine, subalpine fir, spruce, and alpine larch that often have “flags,” short, erect one-sided stems. Alpine cushion such as Douglasia montana are common here and farther along the ridge leading NW to Peak 9096’.
3. There are U-shaped “micro-moraines” of boulders probably created by frost heaving that have “plowed” some soil at their snout as they creep down the south-facing ridge to the north of Carlton Lake. Streamlets run out of them, and the water and soil create a microsite for lush herbaceous vegetation and low shrubs like Labrador tea not normally found on south facing slopes. Pikas and golden-mantled ground squirrels harvest this vegetation. This kind of formation is uncommon in the Bitterroot Range and offers an ecosystem for studying the effects of climate change on wildlife habitat.
4. A well-developed fen at about 8100’, west of Carlton Lake that is built atop sediments 6 to 7 feet deep is home to the northern bog lemming and long-toed salamander. It is bordered by high-elevation wet-site plants like Vaccinium occidentale, Kalmia polifolia, and Ledum glandulosum as well as alpine larch, which is not inhibited by water-saturated soils.
5. A seasonal wetland forest where large old alpine larch trees are being replaced by a subalpine fir-spruce community with riparian herbs and shrubs that borders the south side of Carlton Lake. The seasonal wetland gradually gives way to a moist north facing slope upland forest where alpine larch is slowly being replaced by fir and spruce along and near the trail to the low [7860’] pass leading into the One-Horse Creek drainage.
6. Severe hiker-caused erosion of the heavily trafficked route leading south from the fen to a minor ridge spur and then straight upslope on extremely steep loose rock and gravel to the sharp ridge leading to Peak 9096. Human traffic on what once was a mountain goat trail is also causing damage to small alpine larch trees and native heath and other plants. There is no easy alternative route, such as ascending through the large loose boulders farther east to gain the difficult hogback ridge leading to Lolo Peak. This situation calls for inspection and recreational research to create a better route to the coveted summit of Lolo Peak.
*This information was provided by Dr. Steve Arno in 2018.