Treesearch

Mass attacks of Juglans nigra by Pityophthorus juglandis and its introduction of the canker pathogen Geosmithia morbida lead to branch dieback and, commonly, tree death in locations with outbreaks of thousand cankers disease (TCD). Following initial detection of TCD in Butler County, Ohio, in 2012, and trapping of thousands of P. juglandis, a dramatic decrease in insect population occurred. Dissections of "lingering" TCD-symptomatic J. nigra in 2014 and 2015 were conducted to document the presence of "typical" Geosmithia cankers and other types of damage on branches and main stems....

Prior research suggests that Indigenous fire management buffers climate influences on wildfires, but it is unclear whether these benefits accrue across geographic scales. We use a network of 4824 fire-scarred trees in Southwest United States dry forests to analyze up to 400 years of fire-climate relationships at local, landscape, and regional scales for traditional territories of three different Indigenous cultures. Comparison of fire-year and prior climate conditions for periods of intensive cultural use and less-intensive use indicates that Indigenous fire management weakened fire-climate...

Wood packaging material (WPM) used in international trade, such as crating and pallets, is recognized as a high-risk pathway for the introduction of bark- and wood-infesting insects (borers). The International Standards for Phytosanitary Measures No. 15 (ISPM 15), which sets treatment requirements for WPM, was adopted in 2002. The United States (US) implemented ISPM 15 during 2005–2006. We used 2003–2020 AQIM (Agriculture Quarantine Inspection Monitoring, conducted by USDA APHIS) data, based on standard random sampling, to compare pre-ISPM 15 borer detection rates in WPM entering the US...

Managed wildfires, i.e., naturally ignited wildfires that are managed for resource benefits, have the potential to reduce fuel loads, minimize the effects of future wildfires, and restore critical natural processes across many forest landscapes. In the United States, the 2009 federal wildland fire policy guidance was designed to provide greater flexibility in the use of managed wildfires, but the effects of this policy on wildfires in the western US are not yet fully understood. Our goal was to compare managed and full suppression wildfires and to also analyze the differences between...

The TreeMap 2016 dataset provides detailed spatial information on forest characteristics including number of live and dead trees, biomass, and carbon across the entire forested extent of the continental United States at 30 x 30m resolution, enabling analyses at finer scales where forest inventory is inadequate. We used a random forests machine learning algorithm to assign the most similar Forest Inventory Analysis (FIA) plot to each pixel of gridded LANDFIRE input data. The TreeMap 2016 methodology includes disturbance as a response variable, resulting in increased accuracy in mapping...

Black ash (Fraxinus nigra) forests, which cover over 1.2 million hectares in the Great Lakes Region, are threatened by emerald ash borer (EAB; Agrilus planipennis), which is eliminating native populations of ash throughout the region. Understanding the contribution of black ash wetlands to local and regional species richness is critical in forming effective conservation policies and informing management plans for these imperiled habitats. We measured breeding bird and anuran communities in black ash wetlands and compared them to nearby non-black ash habitats for each taxa: aspen-dominated...

Understanding the effects of landscape management on northern bobwhite (Colinus virginianus; hereafter, bobwhite) population growth requires information about seasonal- and stage-specific demographic parameters linked across the annual cycle. We review results to date from 3 years (2016–2018) of an intensive field study evaluating drivers of bobwhite population dynamics and resource selection during the breeding and non-breeding season in southwest Missouri, USA using data from adult and juvenile bobwhite fitted with radio-transmitters. Land cover of our study sites ranged from large...

The hemlock woolly adelgid (Adelges tsugae (Annand)) is a serious invasive pest of hemlock trees in eastern North America. Multiple biological control agents have been the focus of research aimed at pest management and conserving hemlock communities. Three promising A. tsugae specialist predators are the beetle Laricobius nigrinus (Fender) (Coleoptera: Derodontidae) and flies in the genus Leucotaraxis (Diptera: Chamaemyiidae), Leucotaraxis argenticollis (Zetterstedt), and Leucotaraxis piniperda (Malloch). However, these flies are vulnerable to parasitism by wasps in the genera Pachyneuron...

Tradeoffs occur when deciding between improving forest inventory precision by increasing sample size or by augmenting cluster plot design factors like size or subplot separation distance. The nature of these tradeoffs changes with variation in type and scale of the spatial pattern of the attribute of interest. To understand the impacts of relationships between type and scale of spatial heterogeneity and cluster plot design efficiency, we constructed a factorial simulation experiment and analysed relationships among forest inventory cost, cluster plot design factors, and different spatial...

Humans promote and inhibit other species on the urban landscape, shaping biodiversity patterns. Institutional racismmay underlie the distribution of urban species by creating disproportionate resources in space and time. Here, we examine whether present-day street tree occupancy, diversity, and composition in Baltimore, MD, USA, neighborhoods reflect their 1937 classification into grades of loan risk—from most desirable (A = green) to least desirable (D = "redlined")— using racially discriminatory criteria. We find that neighborhoods that were redlined have consistently lower street tree...