intrusive growth

(interpositional growth) The type of growth exhibited by certain cells when they intrude between other cells that are either not growing or growing at a slower rate. For example, certain members of the Liliaceae have vascular tracheids that elongate at both ends to achieve a length of between 15 and 40 times that of the original. These tracheids insinuate themselves amongst the surrounding cells, disrupting established plasmodesmata. Compare sliding growth , symplastic growth.