Wollemi Pines--The Dinosaur Tree--Threatened


The Australian pine once thought extinct and then rediscovered was reported in Treehugger when nursery cuttings of the unique Dinosaur Tree with the bubbly bark were put on sale to help support conservation efforts. Now the survival of this species is again threatened; this time by Phytophthora cinnamomi, a root-rotting fungus known for its activity as an invasive species moving out from its point of origin in Southeast Asia.
Studies done in 1995 failed to isolate Phytophthora cinnamomi and it was assumed the area was free of the fungus. Nonetheless, the Department of Environment and Conservation identified the fungus as (along with global warming) one of two key threats to the grove. Therefore, measures have been taken for decontamination of all personnel visiting the area for conservation efforts, and the authorities are confident that the approved activities to research and restore the species is not the source of the spread of Phytophthora cinnamomi to the Wollemi Pine. In spite of the very inaccessible and secret location, news of the discovery of this antique species has lured adventurers as evidence of footprints and fire pits have been noted, so the possibility that an unauthorized person tracked the fungus in cannot be ruled out.

Another name for Phytophthora cinnamomi is "Jarrah dieback" which rather well expresses the effect when the soil-borne fungus confronted native Jarrah trees. The Global Invasive Species Database has this to say about the fungus:

"Phytophthora cinnamomi is a destructive and widespread soil-borne pathogen that infects woody plant hosts. It requires moist soil conditions and warm temperatures to be active, but damage caused by the disease most often occurs in summer when plants are drought stressed. P. cinnamomi is one among the most destructive species of Phytophthora, and has been associated with the decline of several forestry, ornamental, and fruit industries as well as over 900 woody perennial plant species. Identification and diagnostic techniques for P. cinnamomi are expensive and require expert attention. Preventative measures and chemical application are the typical forms of control for this species. There are no eradication methods available to combat this species."

Efforts will now focus on confining the existing fungus by horticultural measures such as drainage patterns. Repressing it with fungicides may be attempted if test show the trees are resistant to the chemicals.

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