Treesearch

Cities are increasingly greening vacant lots to reduce blight. Such programs could reduce inequities in urban greenspace access, but whether and how greened lots are used remains unclear. We surveyed three hundred greened lots in Philadelphia for signs of use and compared characteristics of used and nonused lots. We found physical signs of use that might be found in yard space, such as barbeques, picnic benches, and swings, on approximately 10 percent of lots. Logistic regression showed that population density was the only statistically significant predictor of lot use. Findings suggest...

Many studies have examined short-term changes in understory vegetation following prescribed burning. However, knowledge concerning longer term effects on both forest understory and overstory vegetation is lacking. This investigation was initiated to examine changes in understory (herbaceous and shrub) and overstory species composition almost four decades after logging and prescribed burning at the Pike Bay Experimental Forest in Minnesota. The experiment was established in 1964 with a randomized block design with four treatments: control (c); burned in spring 1967 (S0); burned in spring...

Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle (Dendroctonus ponderosae) outbreak and its associated blue stain fungi (Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous disturbance spreads across the landscape. Water cycling may dramatically change due to increasing spatial heterogeneity from uneven mortality. Water and energy storage within trees and soils may also decrease, due to hydraulic...

These data and analyses support the research article late herbivory suppresses deciduous woody plant establishment following salmonid stream restoration” Averett et al. (2017) [1]. The data and analyses presented here include: (1) planting density, survival and growth (two years post restoration) of riparian plantings along an ~11 km stream reach in northeastern Oregon as a function of herbivory treatment (protected/not protected from wild ungulate herbivory), habitat type, and planting species; and (2) abundance and height distributions of naturally occurring deciduous woody species along...

This resource update provides an overview of forest resources in North Dakota based on an inventory conducted by the USDA Forest Service, Forest Inventory and Analysis (FIA) program within the Northern Research Station in cooperation with the North Dakota Forest Service. Estimates are based on field data collected using the FIA annualized sample design and are updated yearly. Information about the national and regional FIA program is available at https://research.fs.usda.gov/programs/fia. For the 2016 inventory, estimates for variables such as area, volume, and biomass are based on 7,595...

Background and Aims Wood is a major innovation of land plants, and is usually a central component of the body plan for two major plant habits: shrubs and trees. Wood anatomical syndromes vary between shrubs and trees, but no prior work has explicitly evaluated the contingent evolution of wood anatomical diversity in the context of these plant habits. Methods Phylogenetic comparative methods were used to test for contingent evolution of habit, habitat and wood anatomy in the mega-diverse genus Croton (Euphorbiaceae), across the largest and most complete molecular phylogeny of the genus to...

The spatial and temporal scales of hyporheic exchange within the stream corridor are controlled by stream discharge and groundwater inflow interacting with streambed morphology. While decades of study have resulted in a clear understanding of how morphologic form controls hyporheic exchange at the feature scale, we lack comparable predictive power related to stream discharge and the spatial structure of groundwater inflows at the reach scale, where spatial heterogeneity in both geomorphic setting and hydrologic forcing are present. In this study, we simulated vertical hyporheic exchange...

An analysis of the urban forest in Houston, Texas, reveals that this area has an estimated 33.3 million live trees with tree canopy that covers 18.4 percent of the city. Roughly 19.2 million of the city’s trees are located on private lands. The most common tree species are yaupon, Chinese tallowtree, Chinese privet, Japanese privet, and sugarberry. Trees in Houston currently store about 2.0 million tons of carbon (7.5 million tons of carbon dioxide [CO2]); valued at $272 million. In addition, these trees remove about 126,000 tons of carbon per year (462,000 tons CO2 per year) ($16.8...

This report highlights key findings from a comprehensive vegetation survey of all forested land across the state of Oregon. A total of 5,180 forested field plots in Oregon were visited by Forest Inventory and Analysis (FIA) crews over a 10-year period from 2001 to 2010. Oregon has 30 million acres of forest, covering nearly half the state. The structure and composition of Oregon’s forests differ considerably across the state, particularly east versus west of the Cascade Range. Western Oregon forests are dominated by higher productivity classes (85 to 224 cubic feet per acre annual growth)...

With the goal of understanding environmental effects of a growing bioeconomy, the U.S. Department of Energy (DOE), national laboratories, and U.S. Forest Service research laboratories, together with academic and industry collaborators, undertook a study to estimate environmental effects of potential biomass production scenarios in the United States, with an emphasis on agricultural and forest biomass. Potential effects investigated include changes in soil organic carbon, greenhouse gas emissions, water quality and quantity, air emissions, and biodiversity. Effects of altered land-management...