Treesearch

Quantifying tree canopy cover is fundamental to applications in forestry and ecology, but estimates vary substantially depending on type of field measurement, imagery, or active sensing used. Our objective was to improve estimates of stand-level canopy cover from standard tree inventory measurements, using representative data collected across diverse forest plant association groups across Oregon, USA. Canopy cover was measured with line intercept sampling on 1706 inventory plots and compared to calculations from individually tallied trees. We investigated adjustments of tree crown area...

Federally designated wilderness areas in the US are mandated to fulfill social and ecological goals. Long-term monitoring is key to this mandate, yet is seldom consistent across boundaries. Our purpose is to compile literature and data to examine the utility of a strategic forest inventory for meeting wilderness management objectives and for enabling coordinated interagency responses to boundary-crossing challenges (e.g., pollution, wildfires, plant invasions, global changes). We provide examples from a national forest inventory (NFI), which provides nationally consistent information that...

Responsible stewardship of temperate forests can address key challenges posed by climate change through sequestering carbon, producing low-carbon products, and mitigating climate risks. Forest thinning and fuel reduction can mitigate climate-related risks like catastrophic wildfire. These treatments are often cost prohibitive, though, in part because of low demand for low-value wood “residues.” Where treatment occurs, this low-value wood is often burned or left to decay, releasing carbon. In this study, we demonstrate that innovative use of low-value wood, with improved potential revenues...

Wildfire is capable of rapidly releasing the energy stored in forests, with the amount of water in live and dead biomass acting as a regulator on the amount and rate of energy release. Here, we used temperature and fuel moisture data to examine climate-driven changes in fuel moisture content over the past three decades. We then calculated the changes in energy release (energy release component and fire radiant energy) for two forests that experienced drought and bark beetle mortality and were subsequently burned by wildfires. We found that mortality transitioned substantial amounts of...

To evaluate impacts of competitive conditions in tree neighborhoods on growth responses as influenced by moisture availability and local environmental conditions, we sampled 102 codominant 40- to 70-year-old coastal Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) in regions with relatively high and low moisture availability. We quantified local environmental conditions (topographic position index, heat load, and soil depth), and the annual basal area increment and climate moisture deficits during two growth periods: a five-year period prior to commercial thinning and years six to 10...

To better understand hydraulic adaptations of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii(Mirb.) Franco) to local climate, we examined genetic (G) and environmental (E) responses of branch hydraulic architecture of 7-year-old saplings from dry and wet climates of origin grown at a relatively dry and a relatively wet common garden site in western Oregon. We sampled 2 years of branch growth from three dry-source and three wet-source families grown at both sites (72 branches, total). Overall, only 4 of the 11 traits had significant genetic (G) effects, whereas 9 traits had...

Experimental forests and ranges (EFRs) are a network of long-term, dedicated research sites that have been established nationwide by the U.S. Department of Agriculture, Forest Service (USFS), and include several collaborating research sites managed by other federal and state land management agencies (Adams et al. 2008, Lugo et al. 2006). Most were originally established to investigate the environmental effects of forest management practices, but, over time, many have become venues for long-term environmental monitoring and for investigations of fundamental ecological processes in these...

Genetic diversity underpins species conservation and management goals, and ultimately determines a species’ ability to adapt. Using freshwater environmental DNA (eDNA) samples, we examined mitochondrial genetic diversity using multigene metabarcode sequence data from four Oncorhynchus species across 16 sites in Oregon and northern California. Our multigene metabarcode panel included targets commonly used in population genetic NADH dehydrogenase 2 (ND2), phylogenetic cytochrome c oxidase subunit 1 (COI) and eDNA (12S ribosomal DNA) screening. The ND2 locus showed the greatest within-species...

Chapters 2 through 19 of this report describe existing research results and monitoring datasets from individual experimental forests and ranges (EFRs) of potential use to water quality regulatory agencies. Research addressing the focus question of biological responses to stream nutrients differs among the reviewed EFRs. For example, all of the reviewed EFRs have studies that might be useful for the reference waterbody approach for developing nutrient criteria, while only some of those EFRs have results that would be applicable to the stressor-response modeling approach. In addition, the...

This chapter is a review and synthesis of research conducted at Luquillo Experimental Forest (LEF) on stream nutrients and biological responses. It is intended to inform national and regional water quality regulatory agencies, such as the U.S. Environmental Protection Agency (EPA) and the Puerto Rico Department of Natural and Environmental Resources, about existing results of relevant scientific studies that are available at LEF, and to identify future field and synthetic research of potential use to regulatory agencies that might be conducted at LEF.