This data publication includes tree measurements taken 2008-2010 in three mixed conifer forests: the Pinaleno Mountains and Santa Catalina Mountains in southeastern Arizona, and the Jemez Mountains (Valles Caldera National Preserve) in northern New Mexico. Tree data measured at all locations include: species, condition, diameter at breast height and maximum vertical height. Additional data available include: effective energy and mass transfer (EEMT) and specific gravity (wood density) of woody species. Another data set, for the Pinaleno Mountains, is included in this publication. The data were collected as part of the RMRS Growth and Demography of the Pinaleno High Elevation Forests research project and the Critical Zone Observatory aerial lidar forest structure validation. The data include diameter at breast height, maximum vertical height, condition and species information; and laboratory-determined cross-dated tree establishment dates, age at collection, computed total biomass, and plot-level Effective Energy and Mass Transfer (EEMT) for each tree. Both of these data sets support Swetnam et al. 2016.