Data comprise measurements of spectral reflectance for quaking aspen (Populus tremuloides Michx.) trees at a range of sites in southwestern Colorado near the town of Crested Butte. Spectra were measured in three different ways: hyperspectral measurements of leaves, hyperspectral measurements of bark, and multispectral measurements of canopies. The first two measurements were made using a handheld spectrometer, while the latter were made via airborne imaging from an unmanned aerial system. In addition to these reflectance data, the dataset also includes information on the genotype and/or ploidy level of each sample, as determined by either DNA microsatellite analysis or flow cytometry. All samples are georeferenced. The data include extracted data and raw imagery.