Garden shade under threat

FOR Western Queenslanders, trees go beyond aesthetic garden ornaments; they provide essential shelter and shade during long and hot summers.

But a naturally occurring yet deadly fungus has recently revived its grip on certain tree species and is threatening to spread thoughout Longreach streets.

For years avid green thumb Tony Emslie has doted upon his three magnificent Morton Bay figs which line the footpath outside his Galah Street home, providing a barrier from the harsh western sun.

However the fungus Ganoderma has infected two of these trees, with the third more than likely to also succumb to the contagious botanical disease.

"I have more or less accepted that these trees are going to go," Mr Emslie said.

"I don’t like the idea, but you have to accept that [Ganoderma] is spreading along the street."

Over 12 months ago, Mr Emslie noticed the first fig tree dropping its leaves and white ball-like mounds appearing at its base.

Bemused by the discovery, Mr Emslie contacted the Longreach Shire Council parks and gardens supervisor Jeff Conaghan.

It was not Mr Conaghan’s first experience with Ganoderma, having seen it devastate a number of trees at the Longreach swimming pool.

"Most of the time, once you see the problem it is too late to save the tree," Mr Conaghan said.

"Ganoderma results in thinning of the foliage and leaves dropping; eventually what they call a fruiting body comes up out of the ground.
"These fruiting bodies are a white fungus that grows up from the trees roots, they then turn brown and can get quite large."

Mr Conaghan said in the last three years five Morton Bay fig trees had been removed from around the Longreach swimming pool, with another infected tree earmarked for removal.

"The incidence in Galah Street was reported in April," Mr Conaghan said.

"But over the past six weeks we have noticed a marked deterioration in one of the trees."

"I’ve given up trying to rake up all the dropped leaves because I can’t keep up," Mr Emslie added.

Ganoderma has been prevalent along the moist coastal fringes of Queensland and New South Wales for the past 20 years, but has been rarely seen in dry climates like the Central West.

Using the wind to spread its spores as well as root-to-root contact, Ganoderma has been attributed to wiping out Townsville’s poincianas population.

Gardening guru and ABC local radio fixture Tom Wyatt from Rockhampton suggests local gardeners be more attentive to established trees to prevent Ganoderma.

"People need to be more careful when extracting trees or digging trenches so not to cause any root damage," Mr Wyatt said. "If there is root damage, then treat it with a copper-based fungicide, especially along exposed sections on footpaths and road ways."

While a cure for Ganoderma is not yet available, Mr Wyatt recommends Condey’s crystals or Dettol.
"One of the biggest mistakes people make is breaking off or hitting off the fungus, because it opens up the spores. Instead, people should paint on Dettol."

For Mr Wyatt, prevention is the key to fighting off a Ganoderma outbreak.

"Because this fungus is yet to attack forestries, not much has been done about it. It’s brought about by home gardeners injuring their trees.

"It’s recommended to contact your local parks and gardens officer if you notice anything suspicious."