Treesearch

Over the past several years, plantings of California native plant nursery stock in restoration areas have become recognized as a pathway for invasive species introductions, in particular Phytophthorapathogens, including first in the U.S. detections (Phytophthora tentaculata, Phytophthora quercina), new taxa, new hybrid species, and dozens of other soilborne species. Restoration plantings may be conducted in high-value and limited habitats to sustain or re-establish rare plant populations. Once established, Phytophthorapathogens infest the site and are very difficult to eradicate or...

Combining tree-ring data and modern temperature observations with paleoclimate proxies and ecological evidence from other Great Basin ranges provides insights into the environmental context of the alpine villages in the Toquima Range during the three millennia of occupation. Throughout this time, the Mt. Jefferson summit plateau above 3380 m, north and east of Alta Toquima and above Dakabah, appears to have been too cold and too harsh to have supported trees. The current alpine condition of the plateau, therefore, is likely to be similar to that in prior millennia. Alta Toquima is located...

There is little information concerning how people in the Global South perceive the benefits and costs associated with urban green areas. There is even less information on how governance influences the way people value these highly complex socio-ecological systems. We used semi-structured surveys, statistical analyses, and econometrics to explore the perceptions of users regarding governance and the benefits and costs, or Ecosystem Services (ES) and Ecosystem Disservices (ED), provided by Neotropical green areas and their willingness to invest, or not, for their conservation. The study area...

Anthropogenic change has been associated with population growth, land use change, and changing economies. However, internal migration patterns and armed conflicts are also key drivers of anthropogenic and demographic processes. To better understand the processes associated with this change, we explore the spatial relationship between forced migration due to armed conflict and changing socioeconomic factors in Colombia, a country which has a recent history of 7 million internal migrants. In addition, we use remote sensing, Google Earth Engine, as well as spatial statistical analyses of...

Wildland fire smoke is visible and detectable with remote sensing technology. Using this technology to assess ground level pollutants and the impacts to human health and exposure is more difficult. We found the presence of satellite derived smoke plumes for more than a couple of hours in the previous three days has significant impact on the chances of ground level ozone values exceeding the norm. While the magnitude of the impact will depend on characteristics of fires such as size, location, time in transport, or ozone precursors produced by the fire, we demonstrate that information on...

Fire has been a source of global biodiversity for millions of years. However, interactions with anthropogenic drivers such as climate change, land use, and invasive species are changing the nature of fire activity and its impacts. We review how such changes are threatening species with extinction and transforming terrestrial ecosystems. Conservation of Earth’s biological diversity will be achieved only by recognizing and responding to the critical role of fire. In the Anthropocene, this requires that conservation planning explicitly includes the combined effects of human activities and...

Ecological restoration is central to the wellbeing of Indigenous communities, who have tended, burned, and harvested a variety of resources across diverse ecosystems in California for millennia. Despite having more tribes and more Native Americans than any other state, California has less land under tribal control than most of the states west of the Continental Divide. Consequently, tribes in the state disproportionately depend on public lands for their well-being. However, through “ecocultural restoration,” both ecosystems and their interconnected Indigenous communities can once again...

The walnut twig beetle, Pityophthorus juglandisBlackman, and its associated fungal pathogen that causes thousand cankers disease, currently threaten the viability of walnut trees across much of North America. During a 2011 assessment of seasonal flight patterns of P. juglandiswith yellow sticky traps baited with the male-produced aggregation pheromone component, 3-methyl-2-buten-1-ol, dramatically reduced catches were recorded when Tree Tanglefoot adhesive was used to coat the traps. In summer 2011, two trap adhesives were tested for potential repellency against P. juglandisin a field...

The prebasic molt is a perilous period for songbirds, characterized by heightened energetic demands and vulnerability to predators. Given these vulnerabilities, songbirds are under selective pressure to locate and use quality habitat during the prebasic molt, potentially resulting in site fidelity between years. In this study, we aimed to determine how differences in breeding and molting activity affected site fidelity for a diversity of species at the landscape scale. To accomplish our objective, we used 31 yr of banding data from northern California and southern Oregon for 16 species of...

Invasive forest pests can cause environmental and economic damage amounting to billions of dollars (US) in lost revenues, restoration and response costs, and the loss of ecosystem services nationwide. Unfortunately, these forest pests do not stay confined to wildland forest areas and can spread into suburban and urban areas, imposing significant costs on local governments, homeowners, and management agencies. In this study, a contingent valuation experiment is used to estimate Florida residents’ willingness to pay (WTP) a monthly utility fee that would protect urban forests from invasive...