SCRUB

This is an intermediate stage between grassland and forest. When an area of grassland is left to its own devices it will soon be colonised by small trees and shrubs. The smaller shrubs will eventually be over-shaded by the taller-growing trees and disappear unless something happens to discourage tree growth.

Some of the colonising woody plants are better able to withstand disturbing influences than others. Thorny plants discourage grazers; some can withstand fire and so on. In this situation of regular disturbance, the growth of tree seedlings is discouraged and certain smaller ‘scrubby’ bushes survive. In this case ‘scrub’ is not an intermediate stage but a stable biotope.