Phenological Monitoring Article author D. Cabello, A. Belaj, L. Rallo, C. Muñoz-Díez, D. Barranco, R. de la Rosa, G. Medina, I. J. Lorite Document classification 1.3.1. Phenological Monitoring Text For monitoring the different phenological stages, a triangle diagram (Figure 1) is used to record the most delayed, common and advanced phenological stages by applying the BBCH scale (Figure 2A: Budburst, 2B: Flowering, and 2C: Ripening). A minimum average flower or fruit load should be present on the assessed tree to ensure a correct evaluation. Text Most common stage Most delayed stage Most advanced stage Figure 1: Phenological triangle Text A B C Figure 2: Phenological stages indicated by numbers for A: Budburst (51-54) and B: Flowering (60-68). For Ripening C: 0 = Deep green, 1 = Green-yellow, 2 = Ripe, 3 = Violet, 4 = Black. (Sanz-Cortes et al., 2002; Barranco and Rallo, 2005; Rapoport and Moreno-Alias, 2017) Text The Budburst process should be evaluated to monitor the following stages: • Beginning of Budburst (BB): first time that stage 52 is observed as the most advanced stage (lower right vertex of the phenological triangle). • Beginning of Full Budburst (BFB): first time that stage 53 is observed as the most common stage (upper vertex of the phenological triangle). • Full Budburst (FB): average date between BFB and EFB. • End of Full Budburst (EFB): last time that stage 53 is observed as the most common stage (upper vertex of the phenological triangle). • End of Budburst (EB): first time that stage 54 is observed as the most common stage (upper vertex of the phenological triangle). Text The flowering process should be evaluated two or three times a week to monitor the following stages: • Beginning of Flowering (BF): first time that stage 60 or 61 is observed as the most advanced stages (lower right vertex of the phenological triangle). • Beginning of Full Flowering (BFF): first time that stage 60 or 61 are observed as the most common stages (upper vertex of the phenological triangle). • Full Flowering (FF): average date between BFF and EFF. • End of Full Flowering (EFF): last time that stage 65 is observed as the most common stage (upper vertex of the phenological triangle). • End of Flowering (EF): first time that stage 67 is observed as the most common stage (upper vertex of the phenological triangle).