03:14
Leading fungi expert on death cap mushrooms
Mycologist Tom May, who is an internationally recognised fungi expert, told the jury death cap mushrooms can only be found beneath or close to oak trees or trees within the oak family.
Dr May, a mushroom expert who was the principal fungi research scientist at the Royal Botanical Gardens, said death caps had a 'symbiotic' relationship with oak trees.
He explained this means death caps can't live without an oak tree.
'In Australia it has only been reported with the oak family,' Dr May said.
The mushroom expert described death caps as mostly orangey in colour, but could be whiteish or brownish.
He said they change their appearance as they matured.
Dr May told the jury death cap mushrooms - known scientifically as amanita phalloides (pictured below) - were believed to have been accidentally introduced into Australia from Europe and were first detected in Victoria in the 1970s.
He said the mushrooms were 'relatively short lived' in the wild due to wet conditions and insects.
Dr May said death caps wouldn't last much longer in a refrigerator due to the fungi being infested with insects that 'keep working away' at the mushrooms.
The jury heard button mushrooms last longer in the fridge because they weren't infested with insects.
Dr May said there were many publicly available online databases that contained information regarding death cap mushrooms.
He said iNaturalist is Australia's largest publicly accessible citizen scientist app for uploading information about fungi.
Dr May told the jury you need an account to post information about wild mushroom, but don't need an account to view 'precise location information'.
'You can readily find the location of certain species,' he said.
Dr May also said iNaturalist contains information on where death cap mushrooms can be found.
He said death caps appear as red dots on a map and when you click on the dot it shows information including the image, date of observation and person who made the observation.
An image shown in court included the exact location of death caps in a suburban park.
The jury heard a death cap was detected in Loch on April 18, 2023.
The doctor said death cap mushrooms have been found in the ACT, NSW and parts of Victoria, including Gippsland towns Outtrim, Loch and Morwell.
In Victoria, death caps grow throughout metro Melbourne to the east into the Dandenong Ranges and in the west to Gisborne and Bendigo, the jury was told.
Overseas, the doctor said death caps, outside of their native Europe, have been detected in the United States and New Zealand, but not in Asia or China.
Dr May said cases involving death cap mushrooms occured when people ingested the deadly fungi by mistake.
Dr May, who published a book in 2021, told the jury toxins found in death caps can be in found other mushrooms.
In 2023, one poisoning involved a Chinese tourist who ate a mushroom, became sick, went to hospital, showed early signs of organ failure, but left hospital a week later.
In 24 other cases of reported wild mushroom poisonings, patients experienced gastro symptoms, but none involved organ damage.
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