The Effects of Burning and Simulated Grazing on Productivity, Forage Quality, Mortality and Flowering of Eight Subalpine Herbs in Kosciusko National Park.

Abstract

The effects of simulated grazing and burning on biomass production, forage quality (CP and DM digestibility), plant mortality and flowering of 4 native perennial grasses (Poa phillipsiana, P. sieberana, Danthonia pilosa and Festuca asperula) and four perennial forbs (Aciphylla simplicifolia, Arthropodium milleflorum, Bulbine bulbosa and Hypochoeris radicata) growing in Kosciusko National Park were studied over a 16-month period.

Cutting at 8-week intervals reduced the amount of regrowth at successive harvests as well as the survival of individuals. The season in which a single cut was made generally had a greater effect on the amount of regrowth than length of the regrowth period. Burning promoted flowering and improved the forage quality of the grasses.

Rabbits bred only when they were able to obtain forage with a minimum protein content of 14%, provided mainly by the forb species. The management implications resulting from the interaction of fire and grazing, particularly by rabbits and domestic stock, for ecosystem quality are discussed.