Treesearch

Concern for tree mortality and damage, and preferences for management interventions, reflect people’s values and cultures. We examine perceptions of tree diseases in two Indigenous communities to provide examples of the types of distress and attitudes that arise when tree diseases significantly damage cultural values. Summaries of yellow-cedar decline as perceived by Tlingit and Haida Alaska Natives and rapid ʻōhiʻa death (ROD) and Native Hawaiian culture underscore the interconnections between local people and local forests and the ways forest diseases can impart a loss of culture and...

Infrequent, large-magnitude discharge (>10 6 m 3/s) outburst floods - megafloods - can play a major role in landscape evolution. Prehistoric glacial lake outburst megafloods transported and deposited large boulders (≥4 m), yet few studies consider their potential lasting impact on river processes and form. We use a numerical model, constrained by observed boulder size distributions, to investigate the fluvial response to boulder deposition by megaflooding in the Yarlung-Siang River, eastern Himalaya. Results show that boulder deposition changes local channel steepness (ksn) up to ∼180%...

Erosion following human disturbance threatens ecosystem health and inhibits effective land use. Mountaintop removal/valley fill (MTR/VF) mined landscapes of the Appalachian Coalfields region, USA, provide a unique opportunity to quantify the geomorphic trajectory of disturbed lands. Here we assess how MTR/VF-induced changes to topography and vegetation influence spatiotemporal erosion patterns in five mined watersheds. We use landscape evolution models starting from pre- and post-MTR/VF topographic data to isolate the influence of mining-induced topographic change. We then constrain ranges...

Environmental DNA (eDNA) sampling is a powerful tool for rapidly characterizing biodiversity patterns for specious, cryptic taxa with incomplete taxonomies. One such group that are also of high conservation concern are North American freshwater gastropods. In particular, springsnails of the genus Pyrgulopsis (Family: Hydrobiidae) are prevalent throughout the western United States where >140 species have been described. Many of the described species are narrow endemics known from a single spring or locality, and it is believed that there are likely many additional species which have yet to...

Taxon-specific quantitative PCR (qPCR) assays are commonly used for environmental DNA sampling-based inference of animal presence. These assays require thorough validation to ensure that amplification truly indicates detection of the target taxon, but a thorough validation is difficult when there are potentially many non-target taxa, some of which may have incomplete taxonomies. Here, we use a previously published, quantitative model of cross-amplification risk to describe a framework for assessing qPCR assay specificity when there is missing information and it is not possible to assess...

The built environment includes human-made or modified landscapes, structures, and infrastructure systems that bring together people, services, and economic activities. This chapter focuses on the built environment found in and around cities and suburbs across the country, where most Americans live and work. Cities and urban areas are also a key part of the country’s culture, nature, and historical heritage. The choices that we make today in cities, suburbs, and the built environment to address climate change will affect the livelihoods, well-being, and quality of life for all Americans in...

The 285 million ha of forestland in the U.S. (Butler et al., 2021) exist within a complex socio-political-economic environment that has fundamentally shaped the current state of the forests and has major implications for the future of the forests. A key element of this social context is ownership; the owners of the land – working within biophysical, social, political, and economic constraints – make decisions about land disposition. They decide whether the land remains forested, how it will be managed, and who will have access to the land and many of the benefits it provides.

Preserving the abundance and stocking of oaks (Quercus spp.) has become increasingly challenging in temperate hardwood forests of the eastern US in recent decades due to a remarkable shift in dominance to mesophytic species (e.g., red maple Acer rubrum). Studies have shown that efforts to sustain oaks while restraining maples yield limited success. Given that a significant portion of forestlands in the eastern U.S. are privately owned, it is critical to assess whether current forest management on cross-ownership forests can achieve those objectives. However, such assessments are rare. In...

Wolves are highly mobile predators and can disperse across a variety of habitats and over long distances. However, less is known about dispersal capabilities across water and among islands. The biogeography of island systems fosters spatially structured local populations, and their degree of connectivity may influence the dynamics and long-term viability of the regional population. We sought to quantify wolf dispersal rate, distance, and dispersal sex bias throughout Prince of Wales Island, a 6670 km2 island in southeast Alaska, and the surrounding islands that constitute the wildlife...

In the United States, more than 1,400 native plant nurseries produce more than a billion seedlings for reforestation and restoration projects every year. Many years of monitoring and research have shown that seedling survival of native plants can be greater when the plants are grown in nurseries and outplanted compared to direct seeding or natural regeneration. Production of high-quality seedlings reduces costs and improves seedling survival and growth after outplanting.