02664nas a2200229   4500008004100000020001400041245014100055210006900196260001000265300001000275490000800285520183700293100001602130700002502146700002002171700001902191700002502210700001902235700002402254700002102278856013502299       2012                        eng d  a0378-112700aRelationships between moisture, chemistry, and ignition of Pinus contorta needles during the early stages of mountain pine beetle attack0 aRelationships between moisture chemistry and ignition of Pinus c  cApr 1  a52-590 v2693 aVery little is known about how foliar moisture and chemistry change after a mountain pine beetle attack and even less is known about how these intrinsic foliar characteristics alter foliage ignitability. Here, we examine the fuel characteristics and ignition potential of Pinus contorta (lodgepole pine) foliage during the early stages of a mountain pine beetle attack. Foliar samples were taken periodically from multiple trees identified as green (healthy, unattacked), recently attacked, or red (dead). The fuel moisture content, chemical composition, and time to ignition of needles from each attack category were quantified. Foliar moisture contents varied by an order of magnitude between the attack categories and were lowest for red needles ([approximately]12% on average), highest for green needles ([approximately]109% on average), and most variable for needles of recently attacked trees. Dry matter proportions of fiber in the needles of attacked and red trees were nearly twice that of green needles. Starch and sugar levels were much lower in the needles of attacked and red trees than green trees. Crude fat contents also differed between the attack categories. Time to ignition was strongly related to time since beetle attack. Ignition times varied from as little as 11 s for red needles to 41 s for green needles. A combined model of foliar moisture content, fiber, and crude fat explained 92% of the variation in the foliar time to ignition. Results show that decreased moisture contents and changes in foliar chemistry increase the foliar flammability of mountain pine beetle-attacked trees. This suggests that less heat would be required to ignite the foliage of attacked trees and thus crown fire potential may be higher in attacked stands as long as foliage is retained on the tree. Published by Elsevier B.V.1 aJolly, Matt1 aParsons, Russell, A.1 aHadlow, Ann, M.1 aCohn, Greg, M.1 aMcAllister, Sara, S.1 aPopp, John, B.1 aHubbard, Robert, M.1 aNegron, Jose, F.  uhttps://weevil.myspecies.info/relationships-between-moisture-chemistry-and-ignition-pinus-contorta-needles-during-early-stages-mou02218nas a2200193   4500008004100000020001400041245015900055210006900214260001300283300001400296490000700310520144900317653002801766100002301794700002501817700002301842700002401865856013501889       2010                        eng d  a0045-506700aPost-harvest seedling recruitment following mountain pine beetle infestation of Colorado lodgepole pine stands: a comparison using historic survey records0 aPostharvest seedling recruitment following mountain pine beetle   cDecember  a2452-24560 v403 aThe extent and severity of overstory lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) mortality from mountain pine beetle (Dendroctonus ponderosae Hopkins) has created management concerns associated with forest regeneration, wildfire risk, human safety, and scenic, wildlife, and watershed resources in western North America. Owing to the unprecedented nature of the outbreak and associated management in the southern Rocky Mountains, it is unknown if the forests that regenerate after this current period of extensive change will differ from those that regenerated in the past. Here, we compare the density and species composition of post-harvest seedling recruits in pre-outbreak (1980-1996) and outbreak stands (2002-2007). Lodgepole pine accounted for more than 95% of post-harvest seedling recruitment and the density of seedlings colonizing clearcuts was equal during both the pre-outbreak and outbreak periods. Compared with harvested areas, the density of tree regeneration was 75% lower in uncut forests and was more evenly distributed among subalpine fir (Abies lasiocarpa (Hook.) Nutt.) and lodgepole pine. This comparison provides evidence that the density of seedling recruitment will be at least as high after extensive pine beetle caused mortality as under healthy, pre-outbreak conditions and that the species composition of stands regenerating after this outbreak will differ between treated and untreated areas.10aDendroctonus ponderosae1 aCollins, Byron, J.1 aRhoades, Charles, C.1 aUnderhill, Jeffery1 aHubbard, Robert, M.  uhttps://weevil.myspecies.info/post-harvest-seedling-recruitment-following-mountain-pine-beetle-infestation-colorado-lodgepole-pine