Pinyon-juniper basal area, climate and demographics data from National Forest Inventory plots and projected under future density and climate conditions

These data were compiled to help understand how climate change may impact dryland pinyon-juniper ecosystems in coming decades, and how resource management might be able to minimize those impacts. Objective(s) of our study were to model the demographic rates of PJ woodlands to estimate the areas that may decline in the future vs. those that will be stable. We quantified populations growth rates across broad geographic areas, and identified the relative roles of recruitment and mortality in driving potential future changes in population viability in 5 tree species that are major components of these dry forests. We used this demographic model to project pinyon-juniper population stability under future climate conditions, assess how robust these projected changes are, and to identify where on the landscape management strategies that decrease tree competition would effectively resist population decline. These data represent estimated recruitment, mortality and population growth across the distribution of five common pinyon-juniper species across the US Southwest. These data were collected by the US Forest service in their monitoring program, which is a systematic survey of forested regions across the entire US. Our data is from western US states, including AZ, CA, CO, ID, MT, NM, ND, NV, OR, SD, TX, UT, and was collected between 2000-2007, depending on state census collection times. These data were collected by the Forest Inventory and Analysis program of the USDA US Forest Service. Within each established plot, all adult trees greater than 12.7 cm (5 in.) diameter at breast height (DBH) are assigned unique tags and tracked within four, 7.32 m (24 ft.) radius subplots. All saplings &lt;12.7 cm &amp;  &gt; 2.54 cm (1 in.) DBH are assigned unique tags and tracked within four, 2.07 m (6.8 ft.) radius microplots within the larger adult plots. Finally, seedlings &lt;2.54 cm DBH are counted within the same microplots as the saplings. Two censuses were conducted 10 years apart in each plot. These data can be used to inform how tree species have unique responses to changing climate conditions and how management actions, like tree density reduction, may effectively resist transformation away from pinyon-juniper woodland to other ecosystem types.

Tags: arizona, biogeography, biota, california, climate-change, climatologymeteorologyatmosphere, colorado, data-release, droughts, dryland-forests, ecosystem-management, effects-of-climate-change, field-inventory-and-monitoring, forest-ecosystems, forest-inventory-plot, forest-management, idaho, juniperus-monosperma, juniperus-osteosperma, juniperus-scopulorum, montana, mortality, nevada, new-mexico, north-dakota, oneseed-juniper, oregon, pinus-edulis, pinus-monophylla, pinyon-juniper-forests, pinyon-juniper-woodland, plot-sampling, population-and-community-ecology, population-dynamics, population-growth, recruitment, rocky-mountain-juniper, singleleaf-pinyon, south-dakota, texas, tree-growth, tree-mortality, tree-recruitment, trees, twoneedle-pinyon, united-states-southwest, usgs-627190ded34e76103cd58701, utah, utah-juniper, vegetation, western-united-states
Organization: Department of the Interior