Abstract
Leaf reflectance changes associated with changes in water stress were analysed in two separate experiments. Results indicate that the variation in reflectance among collections of leaves of a given species all at the same level of water stress is at least as great as the variation in reflectance associated with changesin water stress for a givenleaf collection of that species. The implicationis that results from leaf reflectance-water stress studies have only limited applicability to the remote sensing of plant canopy water stress.