Treesearch

Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) presence in the Stansbury Mountains of north-central Utah has been reported prior to the year 2020, but these reports lack adequate population characterization and the delineation of distinct stands of trees. In summer 2020, we identified and documented the presence of 5 separate stands of bristlecone pine in the Stansbury Mountains. These stands are removed from the nearest bristlecone populations in other mountain ranges by a distance of approximately 120 km; as such, they represent a unique outlier population of the species. We...

High-severity fires and short-interval reburns strongly influence forest structure and composition and may overwhelm forest ecosystem resilience and catalyze persistent shifts to non-forest conditions. Recent increases in annual area burned and severity in the western United States (US) highlight the need to better understand the long-term effects of high-severity fire, including interactions with subsequent fires. In the early 20th century, the northern US Rocky Mountains experienced several fire seasons with widespread, high-severity fires, under fire weather comparable with extreme...

Old growth forests are declining globally, threatening dependent wildlife. Many arboreal old-growth obligates, such as the threatened red tree vole, are difficult to monitor for changes in habitat occupancy, and abundance. Yet, conservation planning relies on this information to prevent population declines. We integrated a range of species, habitat, and landscape change information to develop a dynamic habitat-population model. The spatial individual-based model simulated dynamic patterns of occupancy that responded to annual habitat maps, describing 36 years of observed change. We...

Global concerns are many for the invasive impacts of Phytophthora pathogens on native vegetation, agriculture, nurseries, and urban parks and gardens. We compiled a database of 32 traits on 204 species of Phytophthora including data on each species’ taxonomy (clade and subclade), historical knowledge (years since first described), impacted ecosystems, microenvironments inhabited, dispersal mode, physiology, and morphology. Drawing from approximately 11,394 unique host, pathogen, and country plant disease records from GenBank and other sources, we calculated potential invasiveness of 103...

There is an increasing need to understand how animals respond to modifications of their habitat following landscape-scale disturbances such as wildfire or timber harvest. Such disturbances can promote increased use by herbivores due to changes in plant community structure that improve forage conditions, but can also cause avoidance if other habitat functions provided by cover are substantially reduced or eliminated. Quantifying the total effects of these disturbances, however, is challenging because they may not fully be apparent unless observed at successional timescales. Further, the...

Forest harvest is a primary landscape-scale management action affecting riparian forests. Although concerns about impacts of forest harvest on stream amphibians is generally limited to areas adjacent to harvest, there is a paucity of information regarding potential downstream effects of forest harvest on these species. We designed a before-after, control-impact (BACI) experiment to quantify potential impacts of clearcut logging that included 12-m buffers or smaller variable-width buffers on the distribution and abundance of headwater stream amphibians in adjacent and downstream areas. We...

We evaluated area-based approaches (ABAs) to light detection and ranging (lidar) predictions of plot- and stand-level forest attributes (tree count, height, basal area, volume, aboveground biomass, broadleaf/conifer, and diameter at breast height — “diameter”). ABA methods included post-stratification (PS), ordinary least squares (OLSs) regression, k nearest neighbors (kNN), and random forest (RF). This study was conducted on the Savannah River Site in South Carolina, USA. Plot- and stand-level predictions were validated against fixed-radius 0.04 ha (0.1 acre) plots in 49 ≈2.0 ha (5 acre)...

In airborne laser scanning (ALS)-based forest inventories, there is commonly a discrepancy between the plot shape used for model fitting (typically circular) and the shape of population elements (typically square) where predictions are needed. Circular plots are easy to establish, locate and have the smallest number of edge trees on average. Therefore, a circle is the most common plot shape in both traditional and remote sensing-based forest inventories. In contrast, the shape of population elements used for remote sensing-based predictions is nearly always a square because it enables...

Many tools that identify wildfire risks and hazards across the landscape assume that all houses and properties within a community have the same level of risk. However, there are often substantial differences across properties, such as building materials and distance to overgrown vegetation. Tools that don’t account for parcel-level risk cannot provide the details necessary for informing action on private property, such as maintaining defensible space, posting a visible address sign, or hardening a structure.To provide practitioners with a practical method for assessing how wildfire risk...

Public land managers depend on reliable and readily available data about outdoor recreation in parks and greenspaces. However, traditional recreation monitoring techniques including visitor surveying and counting cannot be implemented over large spatial and temporal scales, especially in remote and undeveloped settings where monitoring is costly. To fill these data gaps, and thereby inform decision-making, this study develops and tests the efficacy of a novel recreation monitoring technique that engages visitors in data collection using a chatbot and text-messages. Drawing on knowledge and...