2025-09-02_REVISION - M2023015 (4)

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London Mountain Clean Up July 2025 J-1 Exhibit J Vegetation Information The vegetation in this high-elevation area (approximately 10,000 feet) consists of several distinct communities. At this elevation in the Southern Rocky Mountains, the landscape falls within the subalpine zone and includes both forested and open areas. 1. Description of Present Vegetation Types Forested areas are dominated by Engelmann spruce (Picea engelmannii) and Subalpine fir (Abies lasiocarpa), which form the primary tree canopy reaching heights of 60-80 feet with approximately 40- 60% total canopy cover. Individual Engelmann spruce can reach heights of up to 100 feet in protected areas, while subalpine fir typically remains shorter at 50-70 feet. The ratio between these species typically favors spruce at about 60:40. The understory in forested areas includes tall shrubs such as Gooseberry (Ribes montigenum) and Red elderberry (Sambucus racemosa), reaching heights of 3-6 feet with approximately 10-15% cover. Low shrubs include Whortleberry (Vaccinium scoparium) forming dense patches 4-8 inches high with 20- 30% cover in suitable areas. In open areas and forest clearings, the vegetation structure shifts dramatically. These areas support a rich herbaceous layer dominated by various grass species including Idaho Fescue (Festuca idahoensis) and Thurber's Fescue (Festuca thurberi), typically reaching heights of 8-16 inches with combined cover of 30-40%. Common forbs include Alpine sunflower (Tetraneuris grandiflora), Colorado Columbine (Aquilegia coerulea), and various species of Penstemon, creating a diverse layer 4-24 inches in height with collective cover ranging from 20-35% depending on local conditions. Riparian corridors and moist areas support distinct vegetation assemblages with higher coverage of willows (Salix spp.), particularly Booth's Willow (Salix boothii) and Wolf's Willow (Salix wolfii), forming dense thickets 6-12 feet tall with 60-80% cover in suitable locations. The herbaceous layer in these areas includes Tufted Hairgrass (Deschampsia cespitosa) and various sedges (Carex spp.) reaching heights of 12-24 inches with nearly complete ground cover of 80-90%. Disturbed areas, particularly those associated with historical mining activity, show modified vegetation patterns with increased presence of early successional species. These areas often support scattered stands of Quaking Aspen (Populus tremuloides) reaching heights of 30-50 feet with variable cover of 20-40%, along with a diverse understory of colonizing forbs and grasses.