Cork Oak Trials In Victoria

John Taylor (bio)

Paper read to the Australian Forest History Society conference in Mt Gambier in October 2015

Cork tree acorns

Introduction

Introduction

The genus Quercus contains 450 to 600 species distributed in all continents in the northern hemisphere, with a few species in central America extending into the southern hemisphere{tip content="Mabberley,David J. 1987. The Plant-Book.  Cambridge University Press"}[1]{/tip}. There are many natural hybrids and so the taxonomy of the genus is disputed.

Quercus suber, the cork oak, occurs naturally around the western Mediterranean. It is a short (20m), spreading, slow growing evergreen tree, adapted to cool moist winters and hot dry summers. In its natural state it grows in an ecological association called the maquis, a shrubland to low forest association of hard leaved, evergreen shrubs and small trees rich in plant and animal species{tip content="Dallman, P R. 1998. Plant Life in the World’s Mediterranean Climates. University of California Press"}[2]{/tip}.

Cork from cork oaks has been used since ancient times as bottle stoppers, footwear, insulation and floats for fishing. Since the 17th Century the production and export of cork has been an important industry in Portugal and Spain. The bark is first harvested when trees are about 25 years old, and thereafter at 9 to 12 year intervals.

Large areas of both natural and planted cork oak forests around the Mediterranean are now threatened as demand for cork falls due to competition from plastic and steel. In future they could be replaced by citrus orchards or timber plantations of Pinus or Eucalyptus.

Cork Oaks in Australia

Cork oaks have been planted in Australia as specimen trees in many parks and gardens since the mid-19th Century. The oldest is said to be in the Royal Tasmanian Botanic Gardens (planted 1857) and the largest at Tenterfield in northern NSW (planted 1861; Figure 1){tip content="Hawker, J. 2003. Cork Oaks in Australia. The Botanic Garden BGANZ"}[3]{/tip}.

 
Cork oak at Tenterfield, northern NSW, planted 1861

Figure 1. Cork oak at Tenterfield, northern NSW, planted 1861

 

The largest plantation of cork oaks in Australia was established in the Mt Stromlo Forest near Canberra in 1917 and 1920. The cork oaks were planted by Charles Weston, Officer in Charge Afforestation{tip content="Charles Weston MBE, forester and horticulturalist, established Canberra’s urban forest between 1913 and 1926."}[4]{/tip}, at the urging of Walter Burley Griffin who supplied the acorns for the initial planting. Cork was harvested from the trees from 1948 to 51 and in 1981 and 2001{tip content="Susan Parsons, retrieved from http://www.nationalarboretum.act.gov.au/living-collection/trees/tree_stories/cork_oaks October 2015"}[5]{/tip}. Now nearly 100 years old, the trees are healthy, though growth has been slow compared to some plantings in Victoria as described later in this paper. The plantation narrowly escaped being burnt in the 2003 bushfires and is now part of the National Arboretum (Figure 2).

 
 

Figure 2. Cork oaks planted 1917 and 1920 in the National Arboretum, Canberra

 

Turning to Victoria, a small plantation of cork oaks was planted in State Forest at Mt Macedon in 1887. Cork from the plantation was harvested in 1930 by the well known cork processing firm of Vogts{tip content="Forests Commission Victoria file 63/792"}[6]{/tip}. The plantation was destroyed in the 1983 bush fires.

In the 1920s Vogts lobbied the government and the Forests Commission Victoria, urging the planting of commercial cork oak plantations to support local industry and reduce imports.

In response the Commission agreed to plant small areas in the Creswick and Beechworth forest districts. There is no information on the files as to what, if anything, happened at Beechworth, but in 1929 cork oak acorns were planted at 8ft by 8ft spacing on two acres in the south western corner of the Mt Beckworth State Forest in the Creswick Forest District (Figure 3). The acorns came from the trees at Mt Macedon. The file contains reports on the small plantation dated 1937 and 1963 – many trees were lost after planting, but the survivors grew well and today are large trees (top height 20m). Cork has not been stripped from these trees.

 

Figure 3. Cork oaks planted 1929 in Mt Beckworth State Forest

 

References
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  1. Mabberley,David J. 1987. The Plant-Book.  Cambridge University Press
  2. Dallman, P R. 1998. Plant Life in the World’s Mediterranean Climates. University of California Press
  3. Hawker, J. 2003. Cork Oaks in Australia. The Botanic Garden BGANZ
  4. Charles Weston MBE, forester and horticulturalist, established Canberra’s urban forest between 1913 and 1926.
  5. Susan Parsons, retrieved from the National Arboretum Website, October 2015
  6. Forests Commission Victoria file 63/792
  7. File 68/1593
  8. Brian Fry, ex Assistant District Forester, pers comm
  9. Athol Hodgson, ex Commissioner of Forests, pers comm