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Forest Health Treatment Needs (continued) Dry dense forest treatment need Currently, dense, multistory forest structure is over-repre- sented on dry sites, especially sites dominated by Douglas- fir. Treating 5,500-7,500 acres of dense dry forest (Table 1) is recommended to shift the landscape from dense to open forest. ln locations with large trees, removing smaller trees and treating fuels with mechanical or fire-based methods will create more fire-, insect-, and drought-resistant forest structure. Favoring ponderosa pine and reducing Douglas- fir and grand fir on drier sites is also recommended. Definitions Vegetation Types Cold forest: Upper elevation mixed-conifer forests with high-se- verityfires every 80-200+ years. Dry forest: Ponderosa pine and Douglas-fir dominated forests that historically had surface fires every 5-25 years. Moist forest Forests that historically had mixed-severity fires every 30-100 years and were composed of fire-resistant (western larch, Douglas-fir) and fire-intolerant (grand fir) trees. Woodland/Steppe: Grass and shrub lands that may have oak woodlands or up to 10% cover of conifers. Forest structute Large tree: Overstory diameter > 20 inches; Medium tree: Over- story diameter 10-20 inches; Small tree: Overstory diameter < 10 inches; Dense canopy: Greater than 40o/o tree canopy; Open can- opln Less than 40o/o tree canopy. Fuels: Shrubs, grasses. small trees, litter, duff, and dead wood. Fuels Treatmenfs.'some combination of mechanical density reduc- tion (commercial or non-commercial) and surface and ladder fuel re- duction (prescribed fire, piling & burning, etc.). Manoged wildfire: fire is allowed to burn under safe conditions to achieve management goals; can be suppressed if conditions change. Current Post-treatment* Dry Forest (18,565 ac) Moist-cold Forest (17,430 ac) I Smalt Open I Med,Large Open S Small Dense I Med-Large Dense Left: Figure 6. Current and post-treatment proportions of forest types and structure classes. * mid-point of range in Table 1 Right Figure 7. Sustainability of current and potential large tree, dense forest based on fire risk and drought vulnerability. Moist and cold dense forest treatment need Dense, multistory forest on moist and cold sites exceeds or is at the upper end of desired ranges throughout the plan- ning area, and patch sizes are too large. Treating 5,500- 9,250 acres of dense forest on moist and cold sites (Table 1, Fig.4) is recommended to reduce the risk of large crown fire and help forests adapt to a warming climate. lncreasing the relative composition of ponderosa pine and western larch is also needed. Following treatments, approximately half of the total moist and cold forest area would remain dense (Fig. 6) to meet habitat, wood production, and other objectives. Open forest mointenonce treatment need Over the next 15 years, an estimated 3,000-5,250 acres of currently open forests on dry and moist sites will need pre- scribed fire, managed wildfire, or mechanical methods to maintain open conditions by reducing surface fuels and small trees. Specific maintenance strategies depend on landowner objectives and time since prior treatments. Sustoinable locations for dense forest with lorge trees Locations with low to moderate current and future mois- ture deficits (Fig.3) and low fire risk (Fig. 2) offer the most sustainable locations to maintain sufficient area and patch sizes of this forest habitat type and associated ecosystem functions. Sustainable locations include the eastern end of the planning area, as well as north-facing slopes in the cen- tral portion and valley bottom areas in the northeastern corner (Fig.7). Large dense forest sustainability HighIa Low Upper Swauk Landscape Evaluation Summary e020) | page 4