The research presented here examines the potential of multipolarization RADARSAT-2 (C-band) and Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) (L-band) for Leaf Area Index estimation over soybeans and corn canopies. A new Leaf Area Index estimation approach is developed based on coupling of two existing models, the Water Cloud Model (WCM) and the Ulaby model.