However, some observations, namely an apical gradation of bud break along a beheaded axis (Cutter and Chiu, 1975; Chern et al., 1993; Zalewska et al., 2010), suggest that a more complex regulation of bud outgrowth is actually taking place after api- cal dominance release. This mechanism, designated as the “apical control”, is described as “the growth suppression of an existing sub-dominant branch by a higher dominating shoot” (Cline and