Treesearch

Fire is a dominant driver of ecosystem patterns and processes across the Rocky Mountains. This chapter describes fire ecology and fire-related management for the major forest types in the Rocky Mountains. Major forest types included are ponderosa pine, Douglas-fir, mixed-conifer, lodgepole pine, spruce-fir, five-needle pines, and aspen. For each forest type we describe historical fire regimes, interactions between fire and other disturbances, departures from historical patterns, and projected future patterns. We explain fire resistance and postfire recovery patterns. We also include...

While emphasis with entomopathogens has often been on inundative releases, we describe here historic widespread inoculative releases of a fungal entomopathogen. Several U.S. states and municipalities conducted inoculative releases of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Erebidae), pathogen Entomophaga maimaiga Humber, Shimazu et Soper (Entomophthorales: Entomophthoraceae) after 1993, as gypsy moth populations spread into the Midwest and North Carolina. This Japanese pathogen first caused epizootics in northeastern North America in 1989 and methods for its inoculative release...

Forests provide key ecosystem services globally, with economic values ranging from $125 to $145 trillion per year (Costanza et al., 2014). Forests are important not only for carbon sequestration goals and global biodiversity (Bonello et al., 2020a; Di Sacco et al., 2021; Palmer, 2021), but also for the economic (e.g., timber), environmental (e.g., water purification), and social (e.g., recreational activities) benefits (Trumbore et al., 2015) they provide (Bastin et al., 2019, 2020). Increasingly, forests are viewed as directly important to human health (Donovan et al., 2013); indeed,...

This report summarizes the potential impacts of N and S deposition on 94 of the most common tree species across the contiguous United States, compiling information from several peer-reviewed Federal and non-Federal sources. We provide information on how the rates of growth and survival for each species respond to N and S deposition, and the ecological roles and ecosystem services provided by these species. This report is part of a three-volume series covering trees (this Volume 1), lichens (Volume 2), and herbaceous understory species (Volume 3). In this volume, we include five categories...

Efficient separation of insects from plant material for quantification and collection is an important component of entomological research. This paper reports on a novel, easily replicable container designed to efficiently collect two different biological control agents dispersing from hemlock (Tsuga spp.) foliage infested with the invasive hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). The container utilizes a simplified Berlese-style funnel design to collect Laricobius spp. (Coleoptera: Derodontidae) larvae dropping from the foliage into a removable bottom...

The impact of fuelwood harvesting on forest structure and composition is not clear, especially on the understudied and scarce Arasbaran forests in Iran. This research compared woody species density, species diversity, forest composition, and regeneration status in areas of continuous and ceased fuelwood harvesting in Arasbaran forests. We expected fuelwood harvesting to decrease stem density, species diversity, tree size (diameter at the breast height (DBH) and height), and shift composition away from preferred fuelwood species. We measured woody species size and frequency and identified...

In addition to impacts on human health and the economy, COVID-19 is changing the way humans interact with open space. Across urban to rural settings, public lands–including forests and parks – experienced increases and shifts in recreational use. At the same time, certain public lands have become protest spaces as part of the public uprisings around racial injustice throughout the country. Land managers are adapting in real-time to compound disturbances. In this study, we explore the role of the public land manager during this time across municipal and federal lands and an urban-rural...

The hydrological functioning of urban trees can reduce stormwater runoff, mitigate the risk of flood, and improve water quality in developed areas. Tree canopies intercept rainfall and return water to the atmosphere through transpiration, while roots increase infiltration and storage in the soil. Despite this, the amount of stormwater that trees remove through these functions in urban settings is not well characterized, limiting the use of urban forests as practical stormwater management strategies. To address this gap, we use ecohydrological approaches to assess the transpiration rates of...

Urban trees play an important role in helping cities adapt to climate change, but also are vulnerable to changes in climate themselves. We developed an approach for assessing vulnerability of urban tree species and cultivars commonly planted in cities in the United States Upper Midwest to current and projected climate change through the end of the 21st century. One hundred seventy-eight tree species were evaluated for their adaptive capacity to a suite of current and future-projected climate and urban stressors using a weighted scoring system based on an extensive literature review. These...

In 1978, Reece Sailer published a seminal retrospective entitled ‘Our Immigrant Insect Fauna.’ His goals were to better understand the origins and historical patterns of alien insect species introductions into the United States and establish a baseline for future work to improve our ability to respond to environmental and agricultural wellbeing threats. We updated Sailer’s study to include information on species introduced recently into the United States and that are now targeted by regulatory agencies. The recent trends (recorded through 2016) are different from those reported by Sailer....