Treesearch

Fiorinia externa Ferris, elongate hemlock scale, was inadvertently introduced to North America from Japan. This insect is particularly problematic on hemlock, Tsuga spp., though it has been reported in association with several other conifers. The evidence that other conifers might be hosts, capable of supporting growing populations of the insect, has not been previously reviewed. Our review confirms that F. externa is an oligophagous pest of members of Pinaceae. Although species of Cupressaceae and Taxaceae have been reported as hosts of F. externa, they seem unable to support population...

Forecasting the response of vegetation to climate change and human actions at global to landscape scales often relies on system models. Many such models represent the composition and demography of vegetation using age class cohorts of species or vegetation types. Forest landscape models (FLM) simulate spatially explicit forest dynamics in response to disturbance and abiotic drivers and constraints at landscape spatial and temporal scales (105 – 108 ha, hundreds of years), and many represent trees as species-age cohorts on a grid of cells to make the model tractable at landscape scales....

Mitigating heat is a vital ecosystem service of trees, particularly with climate change. Land surface temperature measures captured at a single time of day (in the morning) dominate the urban heat island literature. Less is known about how local tree canopy and impervious surface regulate air temperature throughout the day, and/or across many days with varied weather conditions, including cloud cover. We use bike-mounted air temperature sensors throughout the day in New Haven, Connecticut, USA, from 2019 to 2021 and generalized additive mixed models across 156 rides to estimate the daily...

The potential increases in carbon stocks in arid regions due to recent shrub encroachment have attracted extensive interest among both ecologists and carbon policy analysts. Quantifying the shrub root biomass amount in these ecosystems is essential to understanding the ecological changes occurring. In this paper, we proposed a simple nondestructive method for estimating the coarse lateral root biomass of shrubs based on the root counts obtained from ground-penetrating radar (GPR) radargrams. Root data were gathered via field experiments using GPR with antenna center frequencies of 900 MHz...

Background. In most regions and ecosystems, soils are the largest terrestrial carbon pool. Their potential vulnerability to climate and land use change, management, and other drivers, along with soils’ ability to mitigate climate change through carbon sequestration, makes them important to carbon balance and management. To date, most studies of soil carbon management have been based at either large or site-specific scales, resulting in either broad generalizations or narrow conclusions, respectively. Advancing the science and practice of soil carbon management requires scientific progress...

Methods: for sequencing microbial communities are constantly improving, necessitating storage of samples for future analyses. However, tests of different storage approaches have been limited, hindering our ability to use soil samples stored under various conditions to understand how microbial communities may be changing over time. Few studies have directly compared the effects of different storage methods on microbiome composition over month-to-decade time scales. Here, we present evidence from two experiments investigating how microbial community composition differs between soil samples...

Understanding past fire environments is vitally important for applying silvicultural treatments, which often include prescribed burning to restore fire-dependent ecosystems. We have developed a novel method by which witness trees can be used as pyro-indicators to map past fire environments. The stepwise process first involves partitioning witness trees into two classes, pyrophobic and pyrophilic, based on their known ecophysiological traits. Pyrophilic percentages are then calculated at survey corners by dividing the number of pyrophilic trees by the total number of trees. Next, statistical...

The ambient atmospheric environment affects the growth and spread of wildland fires, whereas heat and moisture released from the fires and the reduction of the surface drag in the burned areas can significantly alter local atmospheric conditions. Observational studies on fire–atmosphere interactions have used instrumented towers to collect data during prescribed fires, but a few towers in an operational-scale burn plot (usually >103 m2) have made it extremely challenging to capture the myriad of factors controlling fire–atmosphere interactions, many of which exhibit strong spatial variabili...

Prof. Dr. Dieter Eckstein (1939 - 2021) significantly influenced the global development of dendrochronology and the underlying science of wood biology. Eckstein’s research areas included dendroclimatology, xylogenesis, ecophysiology, and quantitative wood anatomy. His personal and collaborative work continues to improve our understanding of both the natural environment and human cultural development. The techniques he developed and championed resolved long-standing difficulties in the application of tree-ring science to understand both natural processes and human effects on tree and forest...

Wildfire is increasing in frequency, extent, and severity in many parts of the USA. Considering the unequal burden of natural hazards on socially vulnerable populations, we ask here, how are characteristics of social vulnerability associated with wildfire occurrence nationwide, at different scales and across differing levels of wildland–urban interface development? To answer this question, we first identify all non-urban census tracts in the USA that have experienced a wildfire since 1984. Using 26 different measures of social vulnerability, we compare these tracts to non-urban census...