Studies in the ecology of Nothofagus cunninghamii Oerst. II. Phenology

Abstract

After germination, seedling growth of Nothofagus cunninghamii results from spring flushing of lateral buds, combined at 4-5 years of age with continuous growth from an apical bud during summer. Adult trees all flush from lateral buds in spring. In addition occasional sporadic flushes occur in autumn, but decrease in frequency with increase in altitude.

Within the first 4-5 years of life of Victorian N. cunninghamii seedlings, epicormic burl development with the proliferation of dormant buds commences. This epicormic burl is poorly developed on trees in the Surrey Hills area of northwestern Tasmania. It is suggested that burl formation may have been selected by more constant burning in Victoria, where trees able to coppice after fire have both higher growth rate and earlier seed production than seed-produced plants.

Flowering of N. cunninghamii in Victoria is annual and seed production is generally high. Seed viability increases with tree age, and decreases with stand altitude. The average viability at 3300 ft is 45-50%, and production may be as high as 11 x 10⁶ seeds per acre. The effective longevity in the field is 8-9 months, though dry stored seed at room temperature may germinate, with some viability loss, after 2½ years.

The fall of litter in an N. cunninghamii forest is 6.5 tonnes per hectare per year, and the average annual rate of decay is 0.42. N. cunninghamii leaves live for just over 3 years, falling in autumn after the spring growth has matured.