Project Botanist Rob Price found 3 specimens of the plant which is one of the Myrtaceae family. He said Rhodomyrtus psidioides was particularly susceptible to the introduced fungus Myrtle Rust Austropuccinia psidii. More information about Myrtle Rust.
Native Guava had previously been observed at The Gap in 2007 by SOWN life member Robert Whyte when compiling entries for the SOWN web site Plant to Plant list and during a 2011 botanical survey by BRAIN, Brisbane Rainforest Action and Information Network.
SOWN web site Plants to Plant entry for Native Guava Rhodomyrtus psidioides shows a healthy plant and flowers when it was photographed in 2007. This actual specimen has been badly knocked about by 2022 flooding and Myrtle Rust. While it’s producing healthy looking suckers, Rob Price said Myrtle Rust was very likely to affect the suckers as they grew.
Rob Price contacted the Queensland Department of Agriculture and Fisheries (DAF) who are currently making an effort to collect material off the species for propagation. This effort is an attempt to preserve as much of the species genetic diversity as possible in cultivation as it is likely to become extinct in the wild in the coming decade or so. The plant can be grown successfully with the regular application of a systemic fungicide that prevents Myrtle Rust.
Two officers from DAF collected plant material from the Rhodomyrtus psidioides at the end of February 2023. They said of the 20 native species highly susceptible to Myrtle Rust Rhodomyrtus psidioides was the worst affected. Another local species Rhodamnia rubescens Scrub Turpentine is also susceptible to Myrtle Rust.
In February 2023 SOWN’s Protect The Gap Rainforest project completed the final of five botanical walks to map remnant rainforest species in The Gap. The next steps will be to evaluate the findings and consider future programs to restore the local rainforest.
Native Guava Rhodomyrtus psidioides showing the effects of Myrtle Rust. PHOTO: Ed Bennett