Asked by: James Slatter, Feltwell
As tree trunks grow upwards, buds are produced on either side. These buds are initially dormant because the growing tip at the top, called the ‘apical meristem’, produces the hormone auxin, which inhibits their development. Once the apical meristem has grown far enough away, the concentration of auxin near the bud drops and it can begin growing sideways. This sideways shoot also lays down its own buds, which are in turn kept dormant until the shoot’s own growing tip has advanced enough.
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