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Apical dominance is suppression of lateral bud outgrowth by the growing tip of a shoot. Removing that tip can allow previously inhibited buds to grow into branches, explaining why pinching a growing plant can make it bushier. The effect concerns the growth of existing buds, not simply whether they were formed.

It is tempting to attribute the response to one inhibitory substance. Time-resolved experiments in pea instead found that buds began growing after tip removal before local stem auxin content had declined. Sugar redistribution and sucrose feeding implicated resource supply in this early response. The result does not eliminate later hormonal regulation; it shows why measuring the order of events distinguishes a trigger from a correlated consequence.^[ref]

Michael G. Mason is a plant researcher credited as first author of a 2014 study of sugar supply and apical dominance. The paper lists an affiliation with the School of Biological Sciences at the University of Queensland and credits Mason with research design, experiments, analysis and writing.

The team measured the timing of pea bud growth after removal of the shoot tip, alongside changes in stem auxin and sugar supply. Buds began to grow before the measured local decline in auxin; supplying sucrose also promoted release from inhibition. The result challenged a simple account in which depletion of apically supplied auxin must be the immediate trigger. Its strength is the combination of time-resolved observations and a direct resource manipulation, rather than correlation between branching and sugar abundance alone.^[ref]