Treesearch

Reliable predictions of how changing climate and disturbance regimes will affect forest ecosystems are crucial for effective forest management. Current fire and climate research in forest ecosystem and community ecology offers data and methods that can inform such predictions. However, research in these fields occurs at different scales, with disparate goals, methods, and context. Often results are not readily comparable among studies and defy integration. We discuss the strengths and weaknesses of three modeling paradigms: empirical gradient models, mechanistic ecosystem models, and...

Cytochromes P450 family genes (P450s) are found in a diverse array of organisms ranging from bacteria to mammals to plants to arthropods. Although there are exceptions to this rule, organisms generally contain a fairly large number of P450 genes and pseudogenes in their genomes. For instance, among arthropods whose genomes are well characterized, the mosquito, Anopheles gambiae, has about 100; the fruit fly, Drosophila melanogaster, has about 89; and the honeybee, Apis mellifera, has about 46.

Bark beetle colonization action is a biotic stress to the host, which responds to this action by secreting oleoresin. This mixture of several compounds can be highly toxic for the insects. We hypothesized that the first physiological reaction of the insects to these toxic compounds is to metabolize and subsequently use some of them as pheromone precursors. Epithelial cells from the bark beetle's midgut have been demonstrated to be involved in pheromone production (Nardi and others 2002); however, the site(s) and mechanism(s) where the detoxification process occurs are unknown.

Population genetic structure studies made in genus Dendroctonus have been conducted from the perspectives of allopatric and sympatric models. In the first case, host effect and historical contingency were not recognized as a source of variation, while the later considered the host itself as a source of reproductive isolation. Nevertheless, both models show that genus Dendroctonus has the highest values of genetic variation among Scolytidae (Anderson and others 1979; Anderson and others 1983; Higby and Stock 1982; Langor and Spence 1991; Namkoong and others 1979; Roberds and others 1987;...

The recent outbreak of mountain pine beetle (MPB) (Dendroctonus ponderosae) in British Columbia provided an opportunity to examine genetic variation of differential attack and resistance in a 20-year old lodgepole pine open-pollinated (OP) family trial. Approximately 2,500 individuals from 180 OP parent-tree collections (~14 trees per parent), from several geographic collection zones in B.C., were scored for several traits relating to attack, survival, gallery formation, and infection from the fungi associated with MPB, Ophiostoma sp. Successful initial attack was assumed by the presence...

Emerald ash borer (EAB) was first detected in Michigan and Canada in 2002. Efforts by federal and state regulatory agencies to control this destructive pest have been challenged by the biology of the pest and the speed in which it has spread. Invasion dynamics of the beetle and identifying source populations from Asia may help identify geographic localities of potential biocontrol agents. Genetic techniques, such as mtDNA gene sequencing, amplified fragment length polymorphisms (AFLP), nuclear gene sequencing, and microsatellite analysis will help determine the geographic origin of the...

Pityogenes chalcographus is one of the major pests in Eurasian spruce stands. Crossing experiments performed in the mid-1970s suggested race differentiation, and mtDNA analysis of P. chalcographus gave evidence that today’s populations are divided into several clades. The genetic distance between clades favours a model of allopatric origin with a separation about one million years ago while today haplotypes of the major clades exist sympatrically all over Europe. Within the last few years, the use of mtDNA as a sole genetic marker became a matter of critical discussion. It was shown that...

In this, our last editorial as Editors-in-Chief (EICs) of the Journal of Wildlife Management (JWM), we want to outline how this journal has changed in the past few years, make a few comments on our editorial philosophy and what we hope we accomplished, and make a recommendation for expanding the publishing opportunities in The Wildlife Society (TWS).

Baseline wilderness data are of considerable importance for several reasons. One of the primary values of wilderness is as a reference that contrasts with those lands where humans dominate the landscape. Leopold (1941) called wilderness "a base-datum of normality, a picture of how healthy land maintains itself." To realize this value, baseline data on wilderness conditions are needed, for comparison at some future time and for comparison to other lands. Baseline data also contribute knowledge needed to effectively steward wilderness. Baseline recreation data are particularly important to...

Historical low-severity fire regimes are well characterized in ponderosa pine and mixed-conifer forests at many sites in the western United States, but not in the southern interior of British Columbia, Canada. We reconstructed a history of low-severity fires (1750-1950) near the northern limit of ponderosa pine and demonstrated that local-scale spatial variation in fire frequency varied with topography and that the intra-ring position of fie scars (a proxy for fire seasonality) varied somewhat with topography but more strongly by tree species. Fires were significantly more frequent on the...