Woodland Expansion

Conifer expansion results in sagebrush wildlife habitat loss and fragmentation, reduced forage production, decreased resilience to fire and less resistance to cheatgrass invasion. WLFW’s Framework seeks to maintain and grow intact sagebrush rangeland cores through conifer removal in priority landscapes at a pace that exceeds the rate of expansion.

Strategic Approach

WLFW’s approach for tackling this threat prioritizes maintenance of treeless sagebrush rangelands and restoration of early phase expansion areas. Conifer removal is focused along woodland fringes to maintain and grow sagebrush rangeland cores and sage grouse populations, as opposed to isolated cuts in a sea of forested land. For more information on how to apply this strategy, view this technical video:


Spatial Data

The maps below enable practitioners to rapidly visualize and analyze opportunities for threat reduction. Local maps and data should also be incorporated, where available, to refine conservation delivery.

  1. Categorical Tree Cover. This map depicts categorical tree cover classes across the sagebrush biome, annually 1984-present. Class categorization was performed with the RAP vegetation cover product at 30m resolution. Categories serve as a course surrogate for woodland expansion phase: treeless/early phase 1 (0-1%), phase 1 (2-10%), phase 2 (11-20%), and phase 3 (>=21%). It can be used for identification of relatively treeless core areas for proactive management and to monitor effectiveness through time. More details on this product available here. Map of categorical tree cover.

  2. Ecosystem Resilience and Resistance. This map provides a tool for rapid risk assessment across the range of sage-grouse using an index of sagebrush ecosystem resilience to disturbance and resistance to cheatgrass (“R&R”). It was derived using soil temperature and moisture data to depict underlying abiotic conditions that influence R&R. It can be used to assess relative recovery potential after disturbance and inform the level of restoration intervention that may be needed. More details on this product available here. Map of ecosystem resilience and resistance.

  3. RAP Vegetation Cover. These maps provide annual percent cover estimates from 1984 to present of: annual forbs and grasses, perennial forbs and grasses, shrubs, trees, and bare ground. The data can be used to assess biotic conditions to inform management actions and monitor vegetation through time. Annual forb and grass maps provide a useful surrogate for exotic annuals, allowing managers to understand fluctuations through time and track management outcomes. Perennial forb and grass maps can help managers determine if restoration seeding is needed following disturbance or annual grass control. More details on this product available here. Map of annual
cover.

  4. RAP Biomass. These maps provide annual and 16-day aboveground biomass from 1986 to present of: annual forbs and grasses, perennial forbs and grasses, and herbaceous (combination of annual and perennial forbs and grasses). Estimates represent accumulated new biomass throughout the year or 16-day period and do not include biomass accumulation in previous years. The data can be used to assess fine fuels affecting fire cycles and forage availability. Annual forb and grass maps provide a useful surrogate for exotic annuals, allowing managers to understand fluctuations through time and track management outcomes. More details on this product available here. Map of
annual biomass.