ecesis

(i-SEE-sis) noun

The entry or establishment of a plant in a new habitat.

[From Greek okiesis (inhabitation), from oikein (to inhabit). Ultimately from Indo-European root weik- (clan) that is also the forbear of vicinity, village, villa, and villain (originally, a villain was a farm servant, one who lived in a villa or a country house).]
With thanks to wordsmith.org.