Canopy LiDAR Measurements in Hemlock Removal Experiment at Harvard Forest 2005

As the ecological functioning of a forest stand is often related to the spatial organization of the canopy, we used a portable canopy LiDAR (PCL; Parker et al. 2004) to measure volumetric canopy structure in the simulated HWA management treatments. In September and October 2005, prior to leaf abscission, we set up 16 parallel transects spaced 2 meters apart in the 900 m2 (30 x 30 m) interior of each of the eight treatment plots. The orientation of the transects were either north-south or east-west to minimize the difficulty of traversing the stand. The distances to canopy surfaces more than1 m above the ground along the transects were recorded with the PCL. Assuming a constant horizontal sampling rate, the continual height measures were binned into 1 m intervals. From these measures, vertical canopy profiles, canopy openness, canopy rugosity, and other metrics related to the three-dimensional structure of the canopy can be derived. These canopy measures will be repeated minimally at 5 and 15 year intervals to develop an understanding of early structural dynamics and micrometeorological consequences associated with the simulated HWA treatments. (Parker, G.G., D.J. Harding, and M.L. Berger. 2004. A portable LIDAR system for rapid determination of forest canopy structure. Journal of Applied Ecology 41, 755-767).