1. USDA‐ARS, Conservation and Production Research Lab. P.O. Drawer 10 Bushland TX 79012‐0010
2. Geoscience Australia, National Earth Observation Group, Cnr Jerrabomberra Av & Hindmarsh Dr Symonston, ACT 2609, GPO Box 378 Canberra ACT 2601 Australia
3. USDA‐ARS, Hydrology and Remote Sensing Research Lab. Building 007, BARC‐West Beltsville MD 20705‐2350