Lignification
Lignification is the deposition of lignin as plant tissues become more woody and structurally firm. A new mango flush changes from soft, flexible growth to a harder shoot as it matures, although color alone does not measure every internal change. This matters when judging whether a shoot can tolerate handling or serve as suitable propagation material. A hardened stem is not necessarily ready to flower, and excessive toughness does not automatically make old wood a better scion.