Treesearch

Fruit crop-size estimates are little better than indices unless tied to plant abundance. We developed a “standardized fruit crop” (SFC) using 11 years of fruit-density data in replicated transects to estimate long-term average (versus within-year) production by Vaccinium spp. (blueberry), Gaylussacia spp. (huckleberry), and Rubus spp. (blackberry) if applied to shrub-area inventories. We sampled blueberry and huckleberry in mature forest where canopy cover and shrub area were constant, and blackberry—a “pioneer” shrub—in shelterwood harvests where light availability decreased with stand...

The Southern California Adaptation Partnership identified climate change issues relevant for resource management on national forest and national park units in southern California. This partnership assessed the vulnerability of infrastructure, outdoor recreation, and ecosystem services to climate change and developed adaptation options that minimize negative effects of climate change and facilitate transition to a warmer climate.High levels of use and aging roads and facilities on federal lands are increasing the vulnerability of infrastructure to the effects of climate change. Altered...

Background: Experimental forests present unrivaled opportunities to understand the factors influencing vegetation structure many decades after silvicultural treatments or natural disturbances. In this study, we use the western larch-dominated moist mixed-conifer forests at Miller Creek Demonstration Forest (Miller Creek) to better understand the relationship between current vegetation structure, 55 years after two forms of high-intensity disturbance (clearcutting plus broadcast burning, and a high-severity wildfire) and characteristics of the site, the disturbance, and pre-disturbance...

Reforestation success in areas impacted by high-severity wildfire and seasonal moisture limitations require nursery-grown seedlings capable of establishing and surviving in harsh environments. Drought conditioning (i.e. restricted irrigation regimes) has the potential to improve planting outcomes, although assessments of effectiveness based on replicated field trials in operational settings are rare. In 2022, we conducted a drought conditioning experiment on second-year stock of ponderosa pine (Pinus ponderosa), western white pine (Pinus monticola) and two seed sources of western larch...

This report describes the framework of a long-term project on the Santee Experimental Forest comparing hydrological processes and vegetation dynamics between two research watersheds: one formerly dominated by loblolly pine (Pinus taeda) and currently being restored to longleaf pine (P. palustris), and the other an unmanaged mixed pine-hardwood reference watershed. Along with descriptions of the watersheds and the silvicultural methods used in the longleaf pine restoration, this report provides baseline data on overstory conditions, soils, leaf area index, and coarse woody debris across the...

The Northern Rocky Mountains region includes 42 million acres of forest land which is diverse in landownership, management objectives, tree species, site productivities, disturbance regimes, and silvicultural practices resulting in a mosaic landscape. Substantial changes in landownership, management objectives, markets, policy, forest conditions, and silvicultural practices have occurred over the last thirty years. This review provides a synopsis of these changes across different forest types in the region. The U.S. Department of Agriculture, Forest Service remains the largest forest...

Understanding how species-specific traits and density-dependent competition modulate the effects of extreme climate events is essential for informing future forest management strategies. We analyzed the radial growth of western larch (Larix occidentalis) and Douglas-fir (Pseudotsuga menziesii var. glauca) trees growing in unmanaged old-growth stands — and western larch grown at two experimentally controlled densities — at four sites across western Montana, USA. Differences in leaf habit (deciduous vs. evergreen) and divergent water use strategies (anisohydric vs. isohydric) of western...

Everwet tropical forests, defined by the absence of a pronounced dry season, are globally significant carbon sinks, covering roughly 80% of Southeast Asian tropical forests, 30% of the Amazon basin, and 10% of the Congo Basin. Yet the climatic drivers of stem radial growth in these ecosystems remain understudied. The prevailing hypothesis is that growth is primarily light‐limited, as persistent cloud cover constrains photosynthesis. Evaluating this assumption is critical as climate projections for the humid tropics point towards rising atmospheric evaporative demand, episodic drought, and...

Fire is a disturbance that alters nutrient cycling, but its legacy is often reduced to shifts in carbon (C), nitrogen (N), and phosphorus (P). This C:N:P paradigm overlooks the vast suite of other elements critical to decomposer organisms. Post-fire changes in the abiotic environment—especially when interacting with co-occurring stressors such as ultraviolet (UV) radiation—may reorganize the entire multi-element stoichiometric network within litter, yet the direct implications for arthropod decomposer communities remain largely unknown.In a 469-day factorial field experiment in a subtropica...

Connections in mass timber buildings degrade during fire due to charring and temperature-dependent material reduction, leading to significant fastener deformation. This study develops a temperature-dependent Beam-on-Foundation (BoF) formulation for CLT balloon-frame connections exposed to the WOODWISE large-scale compartment fire. The ambient-temperature BoF model was first validated against embedment and single-shear tests from the literature, followed by development and validation of a heat transfer model using thermocouple data from WOODWISE Test #3. The validated temperatures were...