COMPARISON OF TWO TRAINING PRUNINGS ON ´NEGRET´ AND ´GIRONELL´ HAZELNUT CULTIVARS

In modern hazelnut orchards trees are frequently grown on free vase with only one trained stem and a variable trunk height. This pruning system usually varies within the producing areas, mainly according to the ecological conditions, variety vigour, plant quality and the harvesting system used. The influence of two trunk heights (40 and 80 cm from the ground) in vase training on two hazelnut cultivars with different vigour (‘Negret’ and ‘Gironell’) was studied in a trial for 12 crops (1991-2002). The results show that shorter trunks (40 cm) increase tree vigour and improve early bearing. Although sucker emission is bigger for higher trunks (80 cm), it should be considered that with vigorous varieties (‘Gironell’), sucker control and crop mechanization are much easier. Significant differences in yields and nut quality were not observed between the two pruning training systems assayed. This means that, within the range of 40 to 80 cm, the best system for carrying out all the agricultural practices in the hazelnut orchard is open to choice.