Impact of hedging on Washington Navel citrus trees

Abstract: The experiment consisted of hedging citrus trees of the variety Washington Navel with a planting density of 873 plants/ha. The hedge was 2.65 m high, 0.5 m wide on the upper part and 1.5 m on the lower part forming 10 degrees angle to the vertical and NE/SW orientation. The control tree was cut to a ball shape. Considering mean values of three years, hedging showed a high vegetative stretching (7.20 cm) while the control tree had a lengthening of 4.18 cm, with a growth rate of the spring shoots of 6.80 mm and 4.29 mm per day, respectively. As well, a larger spring leaf area was noted as compared to the control tree. This area was 366.55 cm² against 124.22 cm² by branch, respectively. In spite of a more severe pruning in the treatment, the fruit yield was near to that of the control (9.12 kg/tree) with a density of 873 trees/ha. No significant difference was noted for the total amount of chlorophyll between both sides of the hedge (South/East and North/West) for the non-bearing shoots (1.75 and 1.51 mg. g^-1 fresh weight, respectively) and bearing ones (1.57 and 1.51 mg/g fresh weight) contrarily to the control (non-bearing shoots 1.2 and 1.57 mg g^-1 fresh weight; bearing shoots 1.97 and 1.35 mg. g^-1 fresh weight). All stages of maturation occurred earlier in the treatment.