Natural succession

Understanding natural processes of succession and regeneration is helpful when it comes to reconstructing a forest from scratch. Native forests develop over several natural successions where each plant community improves the conditions for the next.

Light-demanding pioneer or primary species such as manuka, kanuka, makomako, karamu, toetoe, poroporo and koromiko will be some of the first to grow on bare ground. This shrubland is followed by secondary colonisers, which include mahoe, ribbonwood, maire and mapou.

Later to establish are the taller emergent species like rewarewa, rimu, totara, matai and kahikatea. Under these trees only the more shade tolerant canopy species such as tawa, kohekohe, hinau and kamahi can survive.

Eventually, the colonising species are replaced by tree ferns, climbing and perching plants and a climax forest is reached. The cycle continues as trees fall through decay or wind, flood or fire.

The soil composition changes as layers of decaying vegetation build up. This rich organic matter is not available on a grassland site. It is therefore important when restoring an area to choose the right plant for the right place to avoid wasting time and money.