Transplanting for conversion to warm season turfgrass.

Warm season turfgrass species (like bermudagrass) seem to be very suitable to Mediterranean climate conditions. They also give an excellent wear resistance to the sport pitches. Transplanting of pre-cultivated warm season turgrass plants (similar to horticultural nursery) is a promising technique which can be efficiently used for turf conversion. It is based on the quick ground cover capacity of these species by means of stolons and rhizomes. Transplanting can be performed both in tilled and untilled soil. A working yard for the conversion of a professional football pitch was assessed in order to evaluate the performaces. The transplant was performed with a 4-row mechanical transplanter which had been adjusted to work in the untilled mowed football pitch. The mechanical transplanter accommodates 4 back-seated operators and 4 walking operators who can manually transplant the plants in case of failure. The working speed of the tractor was less than 1 km h-1, theoretical working time was about 15 h ha-1, actual working time was 28 h ha-1, thus the work efficiency was about 0.52. Fuel consumption was about 28 kg ha-1. Such a low efficiency was due to the difficulty of the operators to remove the plants from the trays and supply the transplanter’s delivery system. In this concern, an automatic transplanter was modified in order to work in untilled soil within a second specific trial. This machine had an automatic system for removing the plants from the trays, like the most advanced robotic transplanters for vegetable crops. Moreover, a specific system for plant deposition in untilled soil was developed by mounting a double disc in front of the furrowers. Plant deposition was tested and a maximum variation of 6 cm in the row was assessed with respect to the expected value. This gap is completely in accordance with this kind of crop.