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Filters: Tags: Invasive species, diseases, pests and their effects on biological communities (X)

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Data represent presence/absence for cedar decline occurrence. Cedar decline refers to the dying or decline of yellow-cedar (Chamaecyparis nootkatensis) forests in Southeast Alaska and is characterized by red or yellow foliage in trees currently dying, or by white-gray snags of old mortality. Mapped snags can be standing dead as long as eighty years. The data were collected via aerial sketch mapping techniques and recorded on 1:250,000 USGS base maps from 500-3000 foot above ground level(AGL) observations. Survey coverage has been most intense for forests adjacent to shorelines and waterways. Data are collected, refined and updated on an annual basis. This data represent not one year's mortality but the cumulative...
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The risk mapping effort was initiated in 1995 with the formation of a group of specialists from several disciplines including representatives from state and other federal agencies to map and identify risk to insect caused tree mortality. An area is defined to be at risk if 25% or more tree mortality (beyond the normal level of approximately 0.6% annually) is expected over the next 15 years. This effort developed a statewide insect mortality risk layer based upon rules and statistics developed for the National forests and expanded to cover all state and private forest land. Rule structures were based primarily upon stand density index and also included, precipitation, percent canopy cover of host species, and host...
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This DataBasin Gallery contains 415 datasets on bark beetle-caused tree mortality in British Columbia and the western United States. Outbreaks of aggressive bark beetle species cause widespread tree mortality, affecting timber production, wildlife habitat, wildfire, forest composition and structure, biogeochemical cycling, and biogeophysical processes. As a result, agencies responsible for forest management in the United States and British Columbia conduct aerial surveys to map these forest disturbances. Here we combined aerial surveys from British Columbia (2001– 2010) and the western conterminous United States (1997–2010), produced 1-km2 grids of the area of crown mortality from bark beetle attack, and analyzed...


    map background search result map search result map SE Alaska Cumulative Yellow-Cedar Decline Tongass National Forest Invasive Plants 2012 Risk of Insect-caused tree mortality, California Rogue River-Siskiyou National Forest Sudden Oak Death Quarantine Areas 2012 Rogue River-Siskiyou National Forest 7th field watersheds free of Port Orford Cedar root rot Rogue-River Siskiyou National Forest Invasive Plants Spatiotemporal patterns of observed bark beetle-caused tree mortality in British Columbia and the western United States Rogue River-Siskiyou National Forest Sudden Oak Death Quarantine Areas 2012 Rogue River-Siskiyou National Forest 7th field watersheds free of Port Orford Cedar root rot Rogue-River Siskiyou National Forest Invasive Plants SE Alaska Cumulative Yellow-Cedar Decline Tongass National Forest Invasive Plants 2012 Risk of Insect-caused tree mortality, California Spatiotemporal patterns of observed bark beetle-caused tree mortality in British Columbia and the western United States