Early stages of plant succession following timber harvesting in the West Barham catchment of the Otway Ranges.  S. G. Harris.  September 1989.  29pp. (unpubl.)

SUMMARY

This report deals with a study of the impacts of timber harvesting in the Otway Ranges on flora values. The study was undertaken in the West Barham catchment in a tall, open-forest of mountain ash of mainly 1919 origin. The floristics and structure of a three hectare study area were determined in summer 1983/84 prior to timber harvesting in that season. Permanent quadrats were established over the study area, and these were used to annually reassess the vegetation for three years following the harvesting and regeneration operations. Prior to harvesting by the clearfelling method, the mountain ash dominated an understorey of wet sclerophyll trees and shrubs and abundant ferns.

All shrub and tree species present on quadrats before harvesting were recorded on the site after harvesting. Seed germination, rather than coppice regrowth, was the major form of regeneration of tree and shrub species.

Many new species appeared on the site following harvesting, the most abundant being native colonisers such as Helichrysum dendroideum and Senecio spp.. As the stand ages, the coloniser plants are expected to be overtopped and gradually disappear. Most fern species, and epiphytic ferns in particular, were adversely affected by harvesting. They are not expected to recolonise the site until conditions that they require (e.g. shady, cool and moist environment) redevelop.

The relationship between seedling density and growth as influenced by seedbed type and overwood shade was examined. The most successful seedling regeneration of eucalypts and understorey trees and shrubs was recorded on loose, bare soil seedbeds that received full sun.