Treesearch

Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these environmental factors. We assessed the effect of N deposition on herbaceous richness for 15,136 forest, woodland, shrubland, and grassland sites across the continental United States, to address how edaphic and climatic...

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by nonanthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models.We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011- 2013. We also tested correlations of territory re-occupancy with oil...

The U.S. Forest Service Forest Inventory and Analysis Program uses visual inspections of trees from bottom to top to record damage that is likely to prevent survival, reduce growth, or hinder capability to produce marketable products. This report describes the types of damage and occurrence as measured across the 24-state northern region between 2009 and 2013. Descriptive statistics and spatial occurrence maps are presented by genus, species, and state. Inter- and intra-species variation, as well as biotic and abiotic disturbance agents, are issues that should be considered while analyzing...

Context. Golden-cheeked warblers (Setophaga chrysoparia), an endangered wood-warbler, breed exclusively in woodlands co-dominated by Ashe juniper (Juniperus ashei) in central Texas. Their breeding range is becoming increasingly urbanized and habitat loss and fragmentation are a main threat to the species' viability. Objectives. We investigated the effects of remotely sensed local habitat and landscape attributes on point occupancy and density of warblers in an urban preserve and produced a spatially explicit density map for the preserve using model-supported relationships. Methods. We...

The past decade could be called a renaissance of urban forestry, driven by mayoral tree planting initiatives and increased attention on city trees as green infrastructure. The political support for urban greening has been fueled by research that quantifies and projects the ecosystem services of planting initiatives (Young and McPherson 2013). Major cities have been launching "million tree" campaigns, hoping that those trees pay us back. In the scholarly literature, doubts have been raised as to whether urban tree planting is more fashion than function (Pincetl et al. 2012). W e have little...

This report provides an overview of forest resources in Massachusetts based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station.Estimates are based on field data collected using the FIA annualized sample design. Results are for the measurement years 2010-2015 with comparisons made to 2005-2010. Forest resource measurements were taken on 614 plots with about 20 percent of the plots measured each year. Estimates will be updated and published annually. For core tables and more information, including definitions and...

This report provides an overview of forest resources in Rhode Island based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. Estimates are based on field data collected using the FIA annualized sample design. Results are for the measurement years 2010-2015 with comparisons made to 2005-2010. Forest resource measurements were taken on 143 plots with about 20 percent of the plots measured each year. Estimates will be updated and published annually. For core tables and more information, including definitions and...

Ecosystem health and sustainability, to a large degree, depend on the performance of keystone or dominant species. The role of climate on population dynamics of such species has been extensively examined, especially for health indicator species. Yet the life-cycle processes and response lags for many species could complicate efforts to detect clear climate signals. Longleaf pine (Pinus palustris Mill.) is such a keystone tree species in the southeastern United States that has declined in both abundance and distribution during the past century. Despite research efforts on multiple fronts,...

These reference ecosystems and historic range of variability may be hard to define or determine, but accepted methods can include cultural evidence such as written descriptions, oral histories, maps and photographs, and survey records (Egan and Howell 2001). Another tactic is to focus on restoring species composition (such as returning the American chestnut) and ecological processes (such as prescribed fire).