Treesearch

1. Tree-species mixture effects (e.g. complementarity and facilitation) have been found to increase individual-tree productivity, lessen mortality and improve recruitment in forests worldwide. By promoting more efficient and complete resource use, mixture effects may also lessen individual-tree-level water stress, thus improving drought resistance. We investigated the influence of mixture effects on tree productivity, mortality and recruitment across broad compositional and moisture gradients in high-elevation Interior West US mixed-conifer communities, where Populus tremuloides(trembling...

Soil microbiomes are rapidly becoming known as an important driver of plant phenotypic variation and may mediate plant responses to environmental factors. However, integrating spatial scales relevant to climate change with plant intraspecific genetic variation and soil microbial ecology is difficult, making studies of broad inference rare. Here we hypothesize and show: 1) the degree to which tree genotypes condition their soil microbiomes varies by population across the geographic distribution of a widespread riparian tree, Populus angustifolia; 2) geographic dissimilarity in soil microbiom...

long-term (LT) stream chemistry studies are used to examine changes in and responses to the environment. Much of the data collected over long periods of time goes through changes in instrumentation, methods, and personnel potentially resulting in changing values. A data user must understand these measures of data quality through quality control (QC) results to know with certainty if trends are real or attributable to other factors. We used the Web of Science database search engine to search for LT stream chemistry studies. For each study, we then determined: record or study length; if QC...

Private landowner participation in management initiatives can be encouraged by interventions, which must resonate with the underlying subjective motivations of the landowners. In this study, we use the Theory of Planned Behavior to gauge the relative influences of (1) attitudes; (2) subjective norms; and (3) perceived behavioral control on landowner intentions to harvest trees threatened by invasive insects. We use a survey (n=696) to estimate the effects of these latent factors among family forest owners in New England. Our results suggest that, overall, normative pressures are the...

As the industry emerges from the pandemic, what challenges await those involved in the construction-based sectors? For perspective, the total value of private construction (residential and nonresidential) put in place in the United States was slightly over a trillion dollars ($1,081 billion) in 2020, up from $1,031 billion in 2019. Spending in all residential categories increased in 2020, including 7.9% for single family, 6.6% for multi-family, and 20.3% for residential improvements. Spending on nonresidential construction however declined by 2.9%.

The Long-Term Soil Productivity Network is providing a systematic examination of the effects of organic matter removal and compaction on a variety of different soils and forest types across North America. Here we report on the 22nd-year survival and height growth of white oak (Quercus alba), northern red oak (Q. rubra), and shortleaf pine (Pinus echinata) on rocky, nutrient-poor soils that have a low to moderate water holding capacity in the Missouri Ozark Highlands. Treatments included three levels of organic matter removal (sawlog, whole tree, and whole-tree plus forest floor) and three...

The walnut twig beetle, Pityophthorus juglandisBlackman, the vector of thousand cankers disease (TCD), poses a significant threat to North American walnut (Juglandaceae Juglans) trees. Despite discovery of TCD-related tree mortality over a decade ago, management options are lacking. This study represents the culmination of several years of investigating the chemical ecology of P. juglandisin hopes of developing a semiochemical repellent to disrupt the beetle’s host colonization and aggregation behaviors. Numbers of P. juglandislanding on semiochemical-treated Juglans regiaL. trees in a...

Introduced mammalian predators are responsible for the decline and extinction of many native species, with rats (genus Rattus) being among the most widespread and damaging invaders worldwide. In a naturally fragmented landscape, we demonstrate the multi-year effectiveness of snap traps in the removal of Rattus rattus and Rattus exulans from lava-surrounded forest fragments ranging in size from <0.1 to >10 ha. Relative to other studies, we observed low levels of fragment recolonization. Larger rats were the first to be trapped, with the average size of trapped rats decreasing over time. Rat...

Tropical forests exert a disproportionately large influence on terrestrial carbon (C) balance but projecting the effects of climate change on C cycling in tropical forests remains uncertain. Reducing this uncertainty requires improved quantification of the independent and interactive effects of variable and changing temperature and precipitation regimes on C inputs to, cycling within and loss from tropical forests. Here, we quantified aboveground litterfall and soil-surface CO2efflux (“soil respiration”; FS) in nine plots organized across a highly constrained 5.2°C mean annual temperature...

The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) is a skin pathogen that can cause the emerging infectious disease chytridiomycosis in susceptible species. It has been considered one of the most severe threats to amphibian biodiversity. We aimed to provide an updated compilation of global Bd occurrences by host taxon and geography, and with the larger global Bd dataset we reanalyzed Bd associations with environmental metrics at the world and regional scales. We also compared our Bd data compilation with a recent independent assessment to provide a more comprehensive count...