The development of the stem, root, or leaf of higher plants does not follow a recognizable pattern in all cases. In some vascular plants, new bundles may be produced within the mass of secondary xylem as is the case in the Bougainvillea stem to the left, In Bougainvillea the stem also produces included phloem tissue, which is buried either side of secondary xylem. In sugar beet, supernumerary cambia may be produced which result in a significant increase in secondary vascular tissue.
In the sweet potato, additional cambia produce some tracheary elements as well as a few phloem elements. These secondary cambia mostly produce additional storage parenchyma exarch (towards the periphery of the structure) and endarch (towards the centre) of the tuber.
Anomalous growth can therefore be defined as a growth form which does not follow recognizable patterns that occur commonly in the majority of vascular plants.