Treesearch

Restoration planning requires a reliable seed supply, yet many projects occur in response to unplanned events. Identifying regions of greater disturbance risk could efficiently guide seed procurement. Using fire in U.S. Cold Deserts as an example, we demonstrate how historic disturbance can inform seed production choices. We compared differences in fire frequency, area burned, and percent of area burned among different management areas, identifying regions of particular need.We also present a case study focused on fire occurrence within important wildlife habitat, specifically looking at...

Old-growth forests are globally valued for their ecological attributes, cultural significance, and in many cases their rarity. Yet, defining and quantifying these forests has been a difficult task. This study developed an approach to consistently estimate extent of old-growth forest on United States Department of Agriculture (USDA) Forest Service National Forest System (NFS) lands, using NFS regional old-growth definitions applied to the US national forest inventory (conducted by the USDA Forest Service Forest Inventory and Analysis [FIA] program). This method was developed in response to...

Decades of research have brought increasing focus to the biotic and abiotic factors associated with bark beetle infestation of North American conifers. Information is lacking, however, regarding beetle-caused mortality for ponderosa pine of the Colorado Plateau. From 1995 to 2019, we installed and periodically remeasured permanent plots in this forest type with a goal of identifying factors related to infestation probability including tree and stand characters, and abiotic factors such as temperature and precipitation. Forty-eight sites were distributed throughout the Colorado Plateau,...

Wildfire has been an important force in shaping biological diversity in forests of western North America. Patterns of reburning helped to maintain heterogenous landscapes with low tree densities that naturally limited the extent of severe stand-replacing fires. However, anthropogenic impacts over the past two centuries have dramatically altered fire activity and its ecological function, creating conditions that promote large and intense fires with no historical analog. Fuels reduction treatments represent proven methods to mitigate extreme fire events, but there is controversy over their...

1. The colonization of suitable yet unoccupied habitat due to natural dispersal or human introduction can benefit recovery of threatened species. Predicting habitat suitability and conflict potential of colonization areas can facilitate conservation planning.2. Planning for reintroduction of gray wolves (Canis lupus) to the US state of Colorado is underway. Assessing which occupancy sites minimize the likelihood of human-wolf conflict during dispersal events and seasonal movements is critical to the success of this initiative.3. We used a spatial absorbing Markov chain (SAMC) framework,...

Bigseed biscuitroot is a widespread western species, ranging from southern British Columbia to southeastern Manitoba and south to California, Nevada, Utah, Colorado, and South Dakota (Fig. 8 – note this figure includes historic and contemporary herbarium records) (Currah et al. 1983; Lesica 2012; Welsh et al. 2016). In Washington and Oregon, it is much more common east of the Cascade Range (Baker 1956; Hitchcock et al. 1961). In California, it occurs as far south as Kern and San Luis Obispo Counties (Munz and Keck 1973).

Pale agoseris is widely distributed throughout the western United States and Canada (Table 1). In the US, it occurs in all states west of Colorado and in the Dakotas, Minnesota, and Michigan (Baird 2006). Distributions of the two varieties overlap but variety glauca occurs farther south and variety dasycephala occurs farther north. In the states and provinces where their distributions overlap, variety glauca generally occupies lower elevation sites and variety dasycephala higher elevation sites (Hitchcock and Cronquist 2018). The varieties become difficult to distinguish in the northern...

Bigflower agoseris occurs in locations west of central Utah. It occurs in southern British Columbia, Washington, Oregon, California, Nevada, Utah, Idaho, and Montana, and is most common in those states bordering the Pacific Ocean (Baird 2006). Variety grandiflora is most common east of the Cascade Mountains and southward on both the east and west side of the Sierra Nevada Mountains to southern California (Fig. 1). Variety leptophylla is most common west of the Cascade Mountains from Vancouver Island through Puget Sound and the Willamette Valley to the Siskiyou-Klamath Mountains of southwest...

Our recent contribution to Global Change Biology found that, globally, two-thirds of protected area units and over half of protected land area are unlikely to serve as steppingstones for many species under a warming climate (Parks et al., 2023). In response, Gillingham and Thomas (2023) point to previous evidence that protected areas have acted as steppingstones based on three studies from Great Britain that examined range shifts.Original publication: Parks, Sean A.; Holsinger, Lisa M.; Abatzoglou, John T.; Littlefield, Caitlin E.; Zeller, Katherine A. 2023. Protected areas not likely to...

Millions of acres of public and private land in the United States are at risk of losing the native plant communities that are central to the integrity of ecosystems. As plant communities decline, the biodiversity they embody is also being rapidly lost, along with a wealth of ecosystem goods and services important to society. There is a long and growing list of threats to plant communities-invasive species, overgrazing, climate change, and altered fire regimes, to name a few, that have collectively accelerated the deterioration of natural landscapes across the country.