TY - JOUR AU - Abidine, Aziz Z. AU - Heidman, Brian C. AU - Upadhyaya, Shrini K. AU - Hills, David J. TI - Autoguidance system operated at high speed causes almost no tomato damage JF - California Agriculture JO - Calif Agr Y1 - 2004/01/01 VL - 58 IS - 1 SP - 44 EP - 47 PB - University of California Agriculture and Nature Resources SN - 0008-0845 UR - http://dx.doi.org/10.3733/ca.v058n01p44 L3 - 10.3733/ca.v058n01p44 AB - This project explored the effectiveness of an autoguidance system based on a real-time kinematic global positioning system (RTK GPS) accurate to the centimeter (about half-inch) in agricultural production. Our objectives were to determine the effect of spacing between cultivator disks or knives and forward tractor speed on plant damage, and of deep tillage operations on drip-tape damage. Two sets of split-plot field experiments were conducted (with processing tomato transplants and direct-seeded tomatoes) in a Yolo loam field on the UC Davis campus. No significant plant damage occurred even at 7 miles per hour (mph) forward speed and cultivator disk spacing of 2 inches from the plant line. In an additional split-plot test, there was no significant damage to drip tape when the fertilizer shank was operated 2 inches from the drip tape at 3.5 mph. This system allows for automatic steering of the tractor and implements along a path close to buried drip-tape and/or plants without damaging them, even at high operational ground speeds.