Publications by authors named "Robert A Progar"

Despite widespread concerns about the anthropogenic drivers of global pollinator declines, little information is available about the impacts of land management practices on wild bees outside of agricultural systems, including in forests managed intensively for wood production. We assessed changes in wild bee communities with time since harvest in 60 intensively managed Douglas-fir (Pseudotsuga menziesii) stands across a gradient in stand ages spanning a typical harvest rotation. We measured bee abundance, species richness, and alpha and beta diversity, as well as habitat characteristics (i.

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Whitebark pine, Pinus albicaulis Engelm., is a subalpine tree endemic to western North America. This species provides multiple ecosystem services and is suffering widespread mortality from mountain pine beetle, Dendroctonus ponderosae Hopkins.

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Article Synopsis
  • - The text discusses the ecological impacts of wildland fires, particularly focusing on how they affect tree mortality, which is important because trees support various biological services.
  • - Researchers created the Fire and Tree Mortality (FTM) database that includes detailed records from over 164,000 individual trees affected by prescribed fires and wildfires in the U.S. between 1981 and 2016.
  • - This database serves as a tool for assessing fire mortality models, improving pre- and post-fire decision-making, and identifying areas where further research is needed regarding fire-induced tree death.
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We summarize the status of semiochemical-based management of the major bark beetle species in western North America. The conifer forests of this region have a long history of profound impacts by phloem-feeding bark beetles, and species such as the mountain pine beetle (Dendroctonus ponderosae) and the spruce beetle (D. rufipennis) have recently undergone epic outbreaks linked to changing climate.

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The balsam woolly adelgid (Adelges piceae (Ratzeburg) (Homoptera: Adelgidae)) (BWA) is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process.

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