Effetti dell'anulazione del tronco nell'olivo (Ascolana tenera)

Effects of girdling with and without removal of a bark ring in «Ascolana tenera» olive-trees, whose charac teristic is the variable yield, are reported in this study. Girdling with and without removal of a bark ring, carried out before anthesis, increased the percentage of setting of 40% the first one and of 70% the second one. The yield levels (resulted definitely low in control) resulted superior to 100% and 300%. At the same time leaf diagnostic showed (between May and October) a decrease of leaf mineral composi tion in leaves from girdled trees regarding N, Ca, Mg, P, Mg rates: in any case girdling with removal of a bark ring showed more intense effects. Considerable yield increases showed no bad influence on fruit morphology and quality.