The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-9 (Terrestrial Ecology) team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. This data set describes the spatial and temporal relationship between foliage nitrogen concentration and photosynthetic capacity in the canopies of black spruce, jack pine, and aspen located within the Northern Study Area (NSA). The data were collected from June to September 1994 and are useful for modeling the vertical distribution of carbon fixation for different forest types in the boreal forest. The data are available in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). Hall, Forrest G. (Editor) and Curd, Shelaine (Editor) and Dang, Qinglai and Margolis, Hank and Coyea, Marie Goddard Space Flight Center NASA/TM-2000-209891/VOL156, NAS 1.15:209891/VOL156, Rept-2000-03136-0/VOL156