Treesearch

Residential landscapes support human well-being and ecological functioning in urban ecosystems. Trees and native plants in yards and neighborhoods positively influence satisfaction, an important component of human well-being and quality of life. However, these patterns may not hold true in arid ecoregions, where the composition of desert vegetation contrasts the tall, broad-leafed trees of temperate regions. The effects of xeric, desert-like landscaping on satisfaction with the neighborhood environment are especially important to consider given the large amount of resources required to...

A long-standing goal of ecology has been to understand the cycling of carbon in forests. This has taken on new urgency with the need to address a rapidly changing climate. Forests serve as longterm stores for atmospheric CO2, but their continued ability to take up new carbon is dependent on future changes in climate and other factors such as age. We have been measuring many aspects of carbon cycling at an unmanaged evergreen forest in central Maine, USA, for over 25 years. Here we use these data to address questions about the magnitude and control of carbon fluxes and quantify flows and...

Gap-based silviculture and legacy-tree retention are strategies that can increase structural and resource heterogeneity while maintaining forest productivity at the stand scale. Nevertheless, areas of delayed regeneration have been noted in openings with some persisting for a decade or more. To better understand the causes of localized recruitment delay and/or near-term failure, we examined spatial patterning of persistent (≥15 years) patches of regeneration failure (≤1 sapling ≥1.37 m tall per 10 m2) at two long-term experimental gap experiments in northern Wisconsin and the Upper...

To a large degree, the sources and stability of soil organic carbon remain poorly constrained. A clear understanding of links among the components of the soil C cycle is hampered by the complexity of the system as well as challenges associated with partitioning bulk soil C into meaningful fractions. A large accidental 14CO2 release at the Oak Ridge Reservation in Tennessee, USA provided a strong label pulse into adjacent, well-studied oak forests, resulting in highly elevated Δ14C values in leaf litter (~1000‰) and roots (~260–450‰). A four-year manipulative study was conducted to determine...

Haven't heard of irregular shelterwood? Don't worry, it's a newer term for professional foresters, too. Irregular shelterwood was developed in Europe and has recently been adapted for North American forests. Practicing foresters say that they have been doing irregular shelterwoods for a while primarily on private lands, but just didn't have the right terminology for it until recent times.

Despite the social and ecological importance of residential spaces across the country, scant research examines urban yard management policies in the U.S. Governance scholarship points to the implementation challenges of navigating policy language. Our research provides an exploration of yard ordinance language, with implications for communities across the U.S. Specifically, we sought to determine whether — and in what instances — vegetation- and groundcover-related yard ordinances in the U.S. are ambiguous or clear. Our findings suggest that ordinances are often ambiguous when referring to...

Environmental changes are anticipated to generate substantial impacts on carbon cycling in peatlands, affecting terrestrial-climate feedbacks. Understanding how peatland methane (CH4) fluxes respond to these changing environments is critical for predicting the magnitude of feedbacks from peatlands to global climate change. To improve predictions of CH4 fluxes in response to changes such as elevated atmospheric CO2 concentrations and warming, it is essential for Earth system models to include increased realism to simulate CH4 processes in a more mechanistic way. To address this need, we...

An examination of hardwood lumber prices in the eastern United States adjusted for inflation and regional differences in forest composition found declines in aggregate (combined species) prices across all regions. Still, the movements of the three aggregate prices examined were highly correlated among regions. The greatest declines in lumber price occurred in the Northeast and Lake States regions, with smaller declines occurring in the Central, Southern, and Mid-Atlantic regions. With the exception of white oak and walnut, prices of high-value species declined more than prices of low-value...

The advantages of clonal forestry have been well described, but little progress has been made in the identification of phenotypes best suited to this method in high-value hardwood species. The genetic variation within, clonal repeatability (broad-sense heritability) of, and Pearson's correlations among phenological, morphological, physiological, and growth traits (N = 22) of black walnut (Juglans nigra L.) were investigated using 25 grafted clonal genotypes. The trees were grown at wide spacing (4.6 m × 6.1 m) in an intensively managed plantation in north-central Indiana, USA. Clonal...

Urban areas can be particularly vulnerable to climate change due to extensive impervious cover, increased pollution, greater human population densities, and a concentration of built structures that intensify impacts from urban heat, drought, and extreme weather. Urban residents are at risk from a variety of climate stressors, which can cause both physical and mental harm. Urban forests and tree cover provide a critical role in helping cities address climate change by supporting greenhouse gas mitigation, reducing the impacts of extreme heat and altered climate that impair human health, and...