Birch - George LaRoi Forest Plot - PIBN - ITRDB CANA560 Birch, J.D. Birch, J.D. PIBN Pinus banksiana Lamb. jack pine earth science/paleoclimate/tree-ring (George LaRoi Forest Plot>LATITUDE 53.40765>LONGITUDE -113.7517) Variation in tree recruitment, mortality, and growth can alter forest community composition and structure. Because tree recruitment and mortality events are generally infrequent, long-time scales are needed to confirm trends in forests. We performed a 50-yr demographic census of a forest plot located on the southern edge of the Canadian boreal forest, a region currently experiencing forest die-back in response to direct and indirect effects of recent severe droughts. Here, we show that over the last 30 yr biomass, basal area, growth, and recruitment have decreased along with a precipitous rise in mortality across the dominant tree species. The stand experienced periods of drought in combination with multiple outbreaks of forest tent caterpillar (Malacosoma disstria) and bark beetles. These insect disturbances interacted to increase mortality rates within the stand and decrease stand density. The interaction of endogenous and exogenous factors may shift forests in this region onto novel successional trajectories with the possibility of changes in regional vegetation type. STUDY NOTES: Chronologies of four co-occurring tree species within a long-term forest plot at the southern ecotone of the Canadian boreal forest. The naming format for each species' cores is as follows: Picea glauca (GLP01A), Betula papyrifera (GLB01A), Pinus banksiana (GLJ01A), Populus tremuloides (GLA01A). NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Birch, J.D. 2019-05-15 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/26792 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/correlation-stats/cana560.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/northamerica/canada/cana560.rwl https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/correlation-stats/cana560.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/northamerica/canada/cana560.rwl English https://www.ncdc.noaa.gov/paleo/study/26792 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/correlation-stats/cana560.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/measurements/northamerica/canada/cana560.rwl Joseph D. Birch, James A. Lutz, E. H. Hogg, Suzanne W. Simard, Rick Pelletier, George H. LaRoi, Justine Karst2019Decline of an ecotone forest: 50 years of demography in the southern boreal forestEcosphere10410.1002/ecs2.2698https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.2698 START YEAR: 1927 AD * END YEAR: 2017 AD -113.7517 53.40765 -113.7517 53.40765