Mechanical Pruning of ‘Clemenules’ Mandarins in Spain: Yield Effects and Economic Analysis

Abstract

Pruning is one of the most expensive tasks in citrus production, and its mechanization could increase the productivity and competitiveness of citrus farms. The effect of mechanical pruning on yield depends on the variety, crop condition, and location; among other factors. The ‘Clemenules’ mandarin variety is one of the most important ones; therefore, the aim of this work was to study the effects of twelve pruning strategies on ‘Clemenules’ yield over four years, and to conduct an economic analysis. These strategies included fully manual pruning, annual alternation of mechanical/manual pruning, mechanical pruning with manual follow-up, and fully mechanical pruning with different types of cuttings. The results showed that pruning strategies affected the yield and fruit size in some years of the study but not when the four years overall are considered. Strategies that annually alternated mechanical pruning with manual pruning had higher yields than the fully mechanical approaches, and similar yields to the manual and control (no pruning) strategies. Furthermore, although the mechanical pruning costs per hectare were as minimum two times less than those with manual pruning, higher net value was achieved with the manual pruning approach followed by alternate annual mechanical/manual pruning. In conclusion, after four years of study, the pruning strategy with the best global results for ‘Clemenules’ mandarin was that which involved annually alternating mechanical (topping and one-sided hedging) and manual pruning. This strategy allows maintaining regular tree dimensions without dry branches inside.