During the spring, measurements of understory leaf extension and canopy coverage were made on several days to describe the phenology of an aspen stand. Measurements of the optical properties of canopy components were made for wavelengths between 0.35 and 2.1 micrometers. Reflectance and transmittance properties of leaves and needles of eight major overstory tree species and three understory shrubs were measured. Multiple measurements of aspen and spruce allow an investigation of the variability of optical properties within a species, spagnum moss and leaf litter. The helicopter MMR data have a spatial resolution of approximately 32 meters.
Several sites have multiple observations, to allow studies of seasonal variation.
The flights were in a 'criss-cross' pattern to allow observation of the same location with multiple sun and view angles. A key goal of the experiment was to use the aircraft measurements to scale up to satellite observations for the remote sensing of biophysical parameters. Biophysical, Morphological, Canopy Optical Property, and Productivity Data on the Superior National Forest. The study area covered a 50 x 50 km area centered at approximately 48 degrees North latitude and 92 degrees West longitude in northeastern Minnesota at the southern edge of the North American boreal forest. Items 1-2 refer to the site and the plot, respectively.