baumzaehlen - Primeval Forests & Their Trees

©2017copyright christoph hase

Styx Tall Trees Forest Reserve, Tasmania, Australia

 

This small (3 km2) reserve – also called Andromeda Reserve – is located in Tasmania’s Styx Valley at an elevation of about 400 metres. In 2013, it was added to the Tasmanian Wilderness World Heritage Site.  It is not untouched - some stumps can be seen. However, it is the tallest broadleaf forest in the world, with 12 Opens internal link in current windowEucalyptus regnans (mountain ash) individuals of at least 90 metres, the tallest reaching 97 metres. The only taller specimen is a single isolated individual reaching 99.8 m found to the south of Hobart, Tasmania.1 However, the Andromeda stand is senescing and most of the tallest mighty trees already have dead tops. The stand mostly regenerated in about 1710 after a wildfire which burned the whole former forest apart from two trees, which are still 150 years older2. E. regnans forests have the highest fire intensities of any vegetation type in Australia3, but species regeneration is dependent on these infrequent stand-replacing wildfires4, which kill the trees and undergrowth but also release seeds from the woody capsules in the E. regnans canopy, to initiate a new generation5. Unlike most Eucalyptus species, E. regnans cannot regenerate vegetatively, which allows it to grow more rapidly because it does not invest in protective bark and storage organs6. The photosynthetic bark of E. regnans may also contribute to the extremely rapid growth7.

 

In addition to E. regnans the canopy layer also has Opens internal link in current windowE. delegatensis (alpine ash). The canopy is very open so the understory is dense and difficult for walking. There are no trails. Tree identification is fairly easy.

 

References:

 

1       http://gianttrees.com.au/

2       Hickey, Kostoglou & Sargison (2000): Tasmania’s tallest trees. Tasforests Vol. 12.

3       McCarthy, M. A., Gill, A. M. & Lindenmayer, D. B. (1999): Fire regimes in mountain ash forest: evidence from forest age structure, extinction models and wildlife habitat. Forest Ecology and Management 124: 193–203.

4       Jackson, W. D. & Brown, M. J. (2005): Pattern and Process in the Vegetation. In Reid, B., Hill, R., Brown, M. & Hovenden, M. (eds.): Vegetation of Tasmania, pp. 11–38. Australian Government, Canberra.

5       Gill, A. M. (1997): Eucalypts and fires: interdependent or independent? In Williams, J. & Woinarski, J. (eds.): Eucalypt ecology, Individuals to ecosystems, pp. 151-167. Cambridge University Press.

6       Tng, D. Y. P., Williamson, G. J., Jordan, G. J. & Bowman, D. M. J. S. (2012): Giant eucalypts – globally unique fire-adapted rain-forest trees? New Phytologist 196: 1001–14.

7       Sillett, Van Pelt, Koch, Ambrose, Carroll, Antoine & Mifsud (2010): Increasing wood production through old age in tall trees. Forest Ecology and Management 259: 976–994.

 

Eucalyptus regnans (mountain ash) stand. All the trees in the photo are about 90 metres tall. Also Dicksonia antarctica (soft tree fern).
Eucalyptus regnans (mountain ash), centre, and Eucalyptus delegatensis (alpine ash), right.