Abstract: Spectral reflectance assessment of turfgrass canopies is likely to enhance our ability to refine irrigation management technology. Reliable spectral detection of water stress is dependent upon knowledge of wavelengths most sensitive to leaf water content. The purposes of this study were (1) to determine wavelengths at which turfgrass canopy reflectance is most sensitive to progressive dehydration in the visible and near infrared portions of the spectrum and (2) to investigate whether different turfgrasses exhibit spectrally unique canopy reflectance responses to progressive dehydration. Two consecutive studies were conducted using established field plots of hybrid bluegrass (Poa pratensis L. x Poa arachnifera Torr.) (HBG), Kentucky bluegrass (Poa pratensis L.) (KBG) and perennial ryegrass (Lolium perenne L.) (PRG). Field plots were brought to field capacity, irrigation was then withheld and spectral reflectance and Leaf Water Content (LWC) measured as dehydration progressed. In study I, turfgrass canopy spectral reflectance within 616-696 nm in HBG, 658-688 nm in KBG and 630-688 in PRG were well correlated to LWC with maximum coefficients of determination (R2) occurring at 664, 672 and 664 nm for HBG, KBG and PRG, respectively. In study II significant coefficients of determination ranged from 642-694, 594-698 and 638-678 nm with maximum r2 occurring at 668, 672 and 660 nm for HBG, KBG and PRG, respectively. Within the near infrared range only KBG exhibited correlation between canopy reflectance and decreasing leaf water content. Within 734-878 nm range, three species exhibited different degree of reflectance change between fully turgid and wilted turf; indicating the rank of canopy reflectance sensitivity to dehydration was KBG>PRG>HBG, the reverse order of their drought resistance ranking.