Myrtle rust (Austropuccinia psidii) monitoring across eastern Australia through May 2026 is showing the usual late-autumn pattern with localised concerns that biosecurity teams are working through. The May reports from state biosecurity agencies, parks services, and nursery industry monitoring groups are worth reading together to get the regional picture.

Queensland. The wet tropics and the southeast Queensland coastal corridors are reporting elevated rust pressure compared to May 2025. The combination of an extended wet season into early autumn and warm overnight temperatures has supported active sporulation later in the year than usual. Native nursery operators in the Sunshine Coast hinterland and the Gold Coast hinterland are reporting active management on susceptible species. Parks teams in the Lamington and Springbrook areas are documenting increased lesion incidence on Rhodomyrtus and Lenwebbia species.

New South Wales. The mid-north coast and the northern rivers are reporting active pressure that is consistent with the 2024 and 2025 patterns. The South Coast reports are quieter, with the cool autumn temperatures dropping infection activity earlier. The Sydney basin reports are mixed, with active monitoring on the threatened species recovery sites in the Royal and the Ku-ring-gai Chase National Parks. The nursery industry compliance reporting through DPI Biosecurity has been steady.

Victoria. The Gippsland and East Gippsland reports are quiet. The Otways monitoring sites are not showing significant activity. The general Victorian read for May 2026 is that the seasonal temperature drop has paused active sporulation, with the watching brief for the spring return.

Tasmania. The northern and east coast monitoring sites continue to show no detection. The Tasmanian biosecurity posture remains on incursion prevention.

Western Australia. The southwest reports are quiet. The northern WA reports are limited but stable. The WA approach to import surveillance on host species has continued through 2026 with the established controls.

Three operational notes from the May 2026 cohort:

The host species watch list has not changed materially this year. The most susceptible genera — Rhodomyrtus, Eugenia, Syzygium, Lenwebbia, and selected Eucalyptus species in the high-susceptibility category — continue to be the focus of active monitoring.

The nursery industry compliance programmes are operating cleanly across the affected states. The disinfection protocols, the host material movement controls, and the documentation discipline at the wholesale and retail nursery level have matured to a workable practice.

The threatened species recovery sites are the highest-attention monitoring locations. The species that have been pushed close to extinction by rust pressure — including Rhodomyrtus psidioides and Lenwebbia prominens — remain under active conservation management. The May 2026 reports from the recovery sites are stable but the underlying population pressure has not eased.

The watching points for spring 2026:

The recovery pattern from any El Niño-influenced dry winter, if one develops. The dry-winter, wet-spring sequence has historically supported rapid rust population growth on susceptible hosts. The seasonal outlook will matter.

The detection of any new genotype incursions through international biosecurity. The current Australian population of Austropuccinia psidii is a known pandemic-strain biotype, and any incursion of a new biotype would change the management picture significantly. The border surveillance work continues to be the most consequential biosecurity layer.

The capacity of the nursery industry compliance system to maintain the standard through the EOFY cycle and into the spring season. The system has held through 2025 and the May 2026 read is that it should hold through the rest of the year.

For practitioners in the conservation, parks, and nursery sectors, the May 2026 monitoring picture is broadly stable with the localised concerns in southeast Queensland and northern New South Wales requiring active management. The agencies are well-coordinated and the operational systems are working. The base case for the rest of the year is more of the same.