As part of the AmeriFlux project, fluxes of energy, mass and momentum are being measured continuously above and below a mixed hardwood forest canopy in the Morgan-Monroe State Forest, Indiana (MMSF 39 10'N, 86 25' W). The area is characterised by small ridge/ravine topography resulting in differences of moisture variability over short distances. Eddy correlation systems have been deployed above the canopy at two different levels (46 m and 32 m) and a third system at 2.5 m above the forest floor. Here we present the initial results of latent and sensible heat and carbon dioxide fluxes, and investigate the dependence of these fluxes on the relevant controlling variables.