Light bars for measuring photosynthetically active radiation (PAR) are set up for calibration at one of the AFSRC research sites. After calibration the light bars are used to measure PAR under different canopy settings. More information about light measurement research at AFSRC can be found at
Feldhake, C. M., J. P. Neel, D. P. Belesky, and E. L. Mathias. 2005. Light Measurement Methods Related to Forage Yield in a Grazed Northern Conifer Silvopasture in the Appalachian Region of Eastern USA. Agroforestry Systems, 65(3):231-239.