Regeneration of podocarps on Mt Tarawera, Rotorua

Abstract

Abstract In the area studied on the east side of Mt Tarawera, Rotorua, seven species of the Podocarpaceae survived the 1886 eruption. Their regeneration since then is described. Dacrydium cupressinum, Phyllocladus glaucus, Podocarpus hallii , and P. spicatus have only regenerated in the vicinity of surviving trees, but Podocarpus dacrydioides, P. ferrugineus , and P. totara have dispersed seeds up to 4.0, 4.8, and 4.8 km respectively from their surviving parents. Establishment of Podocarpus hallii, P. totara , and Phyllocladus glaucus appears to have resumed within 25 years of the eruption, but regeneration of Podocarpus dacrydioides does not appear to have begun until nearly 50 years after the eruption. Information is not available for the remaining three species. In a detailed of study of Podocarpus hallii regeneration about a surviving parent, most of the younger regeneration is found close to the parent tree and the older regeneration is found some distance away. Chances of survival seem to be greater at a distance from the parent tree, and the parent may have a harmful influence on the survival of its progeny.