Myrtle rust attacks members of the myrtacea family, trees that provide fruit and habitat for native species, and stabilise riverbanks in the wet tropics. Photo: Dr. Louise Morin / CSIRO

By Graham Readfearn
23 January 2019
(The Guardian) – Australia must roll out an emergency national response to an invasive plant disease that is rapidly pushing at least four plant species to imminent extinction, experts have told Guardian Australia.
A draft emergency action plan for the fungal disease myrtle rust proposes that a rapid collection of seeds and plant material needs to be mobilised before several species disappear altogether.Botanist Bob Makinson, vice-president of the Australian Network for Plant Conservation, has coordinated the action plan with input from about 90 experts around the country. He says the pathogen could result in at least four species becoming extinct within five years – Lenwebbia sp. ‘Blackall Range’ , Lenwebbia sp. ‘Main Range’ and Rhodamnia rubescens (scrub stringybark, brush turpentine, or brown mallet wood), Rhodomyrtus psidioides (native guava) – with others to follow.“This is extremely urgent. We are almost eight years down the track and we now have species faced with imminent extinction and a problem that’s only going to get worse.”Myrtle rust, first found at a New South Wales nursery in 2010, attacks trees in the myrtaceae family. In Australia, that includes 2,253 species, including iconic trees such as paperbarks and bottle brush. Many exist only in Australia. About 358 Australian species are already known hosts of myrtle rust, and that number is likely to rise.Makinson says myrtle rust is now “fully naturalised” from Moruya, 300km south of Sydney, to Cape York, and west to the Great Dividing Range. The disease has also appeared in the north of the Northern Territory and has been found in gardens and nurseries in Victoria and Tasmania.Andrew Cox, chief executive of the Invasive Species Council, says: “We absolutely need this plan. We could lose an entire series of myrtle plants and we don’t know what could happen then.“These are complex ecological systems and this could wreak havoc across the Australian plant world. This call cannot be ignored any longer. We could and we should have acted years ago.”“If you can’t grow, then you die – and with myrtle rust it’s a pretty slow death. Some of these species will just drop off their perch and nobody will notice.“It’s looking pretty grim so far,” he says, adding about a dozen are heading for extinction.“That extinction is the end point of millions of years of evolution so, to me, that’s pretty profound.” [more]

Calls for emergency action plan as myrtle rust pushes plants to extinction