An Orthman Mk II tracking unit was purchased in October 1991 prior to cotton sowing. The unit was successful in planting CSIRO's Leitch's block using a Kinze planter. Modifications to NSW Agriculture listing rig was conducted over summer to accommodate the tracking sensors which are fixed at the front of the listing rig, together with the manufacture of suitable marking arms to accommodate minimum tillage experiments. The 1992/93 cotton areas have been prepared using the Orthman tracker and has eliminated the 'guess row' errors previously experienced. The tracker will be used through the coming season for inter-row cultivation, now that standard width rows have been constructed