In-growth is the process whereby previously open forests become denser and treed grasslands become more densely covered with young trees.
Incursion
An activity, such as harvesting or road construction, that removes trees in an old-growth management area.
Invasion
The arrival of an organism in an area where it was not formerly represented.
Invader
Plant species that were absent in undisturbed portions of the original vegetation of a specific range site and will invade following disturbance or continued heavy grazing.
Increaser
Plant species, of the original vegetation, that increase in relative amount due to overgrazing.
