Impact of sward properties on the predictability of forage quality and yield in grassland using remote sensing

Remote sensing techniques have been gaining interest due to their potential for providing fast and non-destructive measurements of crop stands. We present the results of a field experiment aimed at determining the impact of sward structural parameters on the estimation of dry biomass yield and forage quality in grasslands based on spectrometric data. Using a portable spectrometer, we measured the red edge inflection point (REIP) of swards of different species composition at three dates following fertilizer application. We analysed the explanatory power of REIP, plant species, sward height and percent ground cover of green foliage for forage quality parameters and yield. We additionally analysed the effect of sward canopy structure on the predictability of yield for individual species. Our results indicate plant species to be an important factor for the prediction of both yield and forage quality. We also found evidence that biomass distribution across sward-height layers and percent ground cover of green foliage are further factors to be considered for the estimation of grassland yield based on spectrometric measurement.