Treesearch

In the western United States and elsewhere, the need to change society’s relationship with wildfire is well-recognized. Suppressing fewer fires in fire-prone systems is promoted to escape existing feedback loops that lead to ever worsening conditions and increasing risks to responders and communities. Our primary focus is how to catalyze changes in fire manager behavior such that responses are safer, more effective, and capitalize on opportunities for expanded use of fire. We daylight deep-seated, systemic drivers of behavior, and in so doing, challenge ingrained ways of thinking and...

Changing climate may impact species through several processes, including phenologic shifts in seasonal timing of food supplies. These temporal changes can create trophic mismatches for species during major life-cycle events such as migration. For long-distance Neotropical–Nearctic migratory songbirds, body condition prior to migration is related to quality and quantity of food supply, which is a function of precipitation and temperature conditions on the wintering grounds. We assessed how future climate-change scenarios might affect wintering habitat of Setophaga kirtlandii (Kirtland's...

The behaviors of Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) during inter- and intrasexual interactions between both solitary and paired individuals at different sex ratios were observed on Acer platanoides L. (Sapindales: Sapindaceae) branches in the laboratory. Intrasexual contact was generally ignored by females, but between males resulted in battles from which one male ultimately retreated. When male size differed, larger males won battles, whereas equally sized males split the wins and battled longer. When males initiated intersexual contact, they quickly found...

Emerald ash borer (EAB) is an invasive beetle that kills native North American ash species, threatening their persistence. A classical biological control program for EAB was initiated in 2007 with the release of three specialized EAB parasitoids. Monitoring changes in the health and regeneration of ash where EAB biocontrol agents have been released is critical for assessing the success of EAB biocontrol and predicting future changes to the ash component of North American forests. We sampled release and control plots across southern Michigan over a three-year period to measure ash health...

Understanding global change processes that threaten species viability is critical for assessing vulnerability and deciding on appropriate conservation actions. Here we combine individual-based and metapopulation models to estimate the effects of climate change on annual breeding productivity and population viability up to 2100 of a common forest songbird, the Acadian flycatcher (Empidonax virescens), across the Central Hardwoods ecoregion, a 39.5-million-hectare area of temperate and broadleaf forests in the USA. Our approach integrates local-scale, individual breeding productivity,...

Biological invasions by insects that vector plant pathogens have altered the composition of natural and urban forests. Thousand cankers disease is a new, recent example and is caused by the complex of walnut twig beetle, Pityophthorus juglandis, and the fungus, Geosmithia morbida, on susceptible hosts, notably some Juglans spp. and Pterocarya spp. Host colonization by P. juglandis may be particularly important for disease development, but the beetle's host range is not known. In the United States and Italy, this insect has expanded its geographic range by colonizing naïve hosts. The...

Flame and mass loss data for chaparral, a mixture of shrub plants from the Mediterranean climate zone of southwestern North America, from five previously reported experiments were used to evaluate several published models relating flame characteristics to mass loss and heat release rates. These data are unique with fuel moisture content ranging from 0.36 to 0.94 (dry basis); the study used mass loss rates which included water loss. Fit of the data to Froude number correlations developed by Albini, Byram, Nelson and Thomas and heat release rate—flame length correlations by Heskestad,...

A study of commercial timber-harvesting activities in Montana was conducted during 2011 to 2016 to estimate growing-stock removals, characterize current tree utilization and logging operations, and assist with estimating the amount of woody biomass left onsite after harvesting. Sample logging sites were selected within major geographic regions proportional to 5-year timber harvest volumes. A two-stage sampling method was used to compute State-level logging utilization factors. Results of the study indicated that in Montana, for every 1,000 cubic feet (CF) delivered to the mill, harvesting...

On a warm July day in 2014, our group headed out to a field tour on the Mark Twain National Forest. The purpose of the trip was to learn firsthand what stakeholders thought of the Missouri Pine-Oak Woodlands Restoration Project. As wildlife ecologists and foresters, we were well aware of the conservation issues for this ecosystem and the ecological benefits of restoring open forests. On this visit we heard conservation agencies, an NGO, and even a local landowner voice their support for the project. It soon became clear, however, that not everyone agreed with the goals or the management...

Conserving multiple facets of biodiversity is important for sustaining ecosystems. However, understanding relationships between faunal diversity and measurable ecosystem quantities, such as heterogeneity and productivity, across continental scales can be complicated by disparate methods. We developed standardized approaches using lidar data and spectral greenness data (via NDVI; Normalized Difference Vegetation Index) from 637 sampling plots across four sites in North America, Europe, and Asia to test the local effects of habitat heterogeneity and productivity on taxonomic, functional, and...