Treesearch

Forests in cities are important social and ecological resources that vary in spatial extent, configuration, and ownership across urban areas, yet these patterns are not well described. Using high resolution urban tree canopy maps and planimetric data from three major cities of the eastern United States (New York, NY; Philadelphia, PA; Baltimore, MD), we distinguish patches of forest from other tree canopy types. We then compare forest patch spatial characteristics and ownership across the three cities. Baltimore has the greatest citywide forest patch cover (8.3 %) and forest patch area per...

Emerald ash borer (Agrilus planipennis Fairmare) is a destructive invasive insect pest of ash trees (Fraxinus spp.) in North America. Monitoring ash regeneration within post-invasion forests is essential to assess ash persistence in North America. We recorded density of overstory ash [> 10 cm diameter at breast height (DBH)], ash recruits (2–10 cm DBH), ash saplings (≥ 45 cm in height; < 2 cm DBH), and ash seedlings (< 45 cm in height), along with canopy dieback of overstory ash and recruits in four post-invasion areas in south-central Michigan, USA. We also recorded density of all other...

Climate change may transform peatlands from net carbon (C) sinks to C sources, which could result in a positive feedback to global warming. Warmer temperatures might lower water tables, increase the abundance of shrubs, slow Sphagnum and sedge growth and further accelerate the decomposition of dissolved organic matter (DOM) with a concomitant release of C from the surface. Studies in which vascular plant functional groups (PFGs) in peatlands have been manipulated to mimic the potential effects of a warming climate on DOM are scarce. In the subject study, seasonal effects of PFGs on the...

Hybridization between eastern and western lineages of the biological control agent, Leucotaraxis argenticollis (Zetterstedt) (Diptera: Chamaemyiidae), was demonstrated in the laboratory. The western lineage is abundant on hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae) in western North America while a genetically distinct eastern lineage feeds mostly on pine adelgids (Hemiptera: Adelgidae: Pineus spp.). Western flies have been released in eastern North America but establishment has not been observed. When reared on A. tsugae in the laboratory, many eastern L. argenticol...

Civic capacity to care for the urban environment is a key factor in urban sustainability efforts. Civic environmental stewardship groups play critical roles in solving governance challenges associated with sustainability, serving as brokers, acting as stewards, advocating for policies, and being repositories of social-ecological memory. Understanding the existing capacity of such groups to create social-ecological outcomes across the urban landscape enables better planning and implementation of equitable nature-based solutions. In this paper, we draw upon existing frameworks of community...

Using Planetscope imagery, we trained a random forest model to detect Callery pear (Pyrus calleryana) throughout a diverse urban landscape in Columbia, Missouri. The random forest model had a classification accuracy of 89.78%, a recall score of 0.693, and an F1 score of 0.819. The key hyperparameters for model tuning were the cutoff and class–weight parameters. After the distribution of Callery pear was predicted throughout the landscape, we analyzed the distribution pattern of the predictions using Ripley’s K and then associated the distribution patterns with various socio-economic...

The boreal forests of Eurasia form the largest contiguous terrestrial biome in the world, providing numerous ecosystem functions and services for human societies. Temperatures are increasing most rapidly in high northern latitudes, altering tree growth and competition dynamics, and modifying disturbance regimes. The effect of these cumulative changes on the ecosystem functions provided by boreal forests is difficult to predict. We used the process-based LANDIS-II forest landscape model to evaluate how climate change and timber harvesting will interact to alter the production of ecosystem...

The ambrosia beetle Megaplatypus mutatus (Chapuis) (Coleoptera: Curculionidae: Platypodinae) is native to South America and is an important forest pest in poplar plantations in Argentina as well as in Italy where it has been introduced. Unlike most platypodine ambrosia beetles, it targets specifically live and vigorous trees. We report for the first time an attack on African mahogany trees, Khaya grandifoliola C. DC., by M. mutatus in Brazil, indicating its preference for trees with larger diameters. Most attacked trees exhibited only one or two gallery entrance holes, primarily along the...

Urban forests provide ecosystem services that are public goods with local (shade) to global (carbon sequestration) benefits and occur on both public and private lands. Thus, incentives for private tree owners to invest in tree care may fall short of those of a public forest manager aiming to optimize ecosystem service benefits for society. The management of a forest pest provides a salient focus area because pests threaten public goods provision and pest management generates feedback that mitigates future risks to forests. We use a game theoretic model to determine optimal pest treatment...

Due to concentrated surface water runoff, edge-of-field buffers may ineffectually mitigate agricultural nonpoint source pollution. To address this challenge, we evaluated the AgBufferBuilder (ABB) tool, which designs nonlinear buffers based on hydrologic modeling. ABB was tested on 45 areas of interest (AOIs) within the Saginaw Bay basin in central Michigan (United States) to determine the effectiveness of ABB at improving sediment trapping efficiency from runoff compared to existing conditions. While ABB did not consistently achieve the target sediment trapping efficiency rate of 75% in...