Mick Schaefer, ex-PARG PhD student and now CSIRO-UNE research scientist, has returned for one week only to complete a combined sensor trial over pasture utilising Sick lidar technology, Holland Scientific Red/NIR and thermal sensing plus his own Optical Ranging and Reflectance sensor (ORRS) developed during his time as a postgraduate student. The trial aims to assess the ability of ranging technology to increase the biomass prediction over standard Red/NIR optical biomass sensors. The holy grail of biomass sensing is the ability to measure total biomass, green and dead fraction, in a pasture sward. Current optical sensors work well in totally green monoculture swards, but add a different species and a dead fraction and proximal sensed biomass estimation lose accuracy quickly.