Rural
25 October, 2024
Keep an eye out for pasture
Queensland graziers are urged to keep an eye out for pasture dieback this spring.
Department of Agriculture and Fisheries (DAF) principal pasture agronomist Gavin Peck said the condition, which caused premature death of tropical and sub-tropical grasses, spread to new areas last year.
“Previously, pasture dieback generally affected high-yielding sown-grass pastures in regions with more than 600mm of average annual rainfall,” Mr Peck said.
“However, last summer it spread into western districts of southern, central and northern Queensland where there was good summer rainfall.”
Mr Peck encouraged graziers to check early growth and condition now, so they have time to manage towards assisting natural recovery, or to renovate or replace the pasture if required.
“Initial symptoms of pasture dieback include leaf discoloration and unthrifty growth, before the pasture dies in patches.
“The dead patches are then colonised by broadleaf weeds or legumes—both of which are unaffected by pasture dieback.”
Mr Peck said graziers should check dieback-affected pastures for natural recovery and decide if they needed to replace the pasture.
“Paddocks that have surviving plants or good density of new grass seedlings can rapidly recover, especially with the use of broad-leaf herbicides to control weed competition.
“Severely affected pastures that do not have good grass seedling density or have had chronic multi-year pasture dieback can be renovated or replanted to legumes and more tolerant grasses.”
DAF principal pasture agronomist Stuart Buck, who leads pasture dieback research in Queensland, said the condition was caused by pasture mealybug, a sap-sucking insect which was mostly spread by wind.
“Pasture dieback is likely to occur when pasture mealybugs are present in warm and wet conditions with a dense body of susceptible grass,” he said.
DAF has a range of dedicated tools and resources to help graziers identify and manage pasture dieback, including pasture dieback workshops available on the FutureBeef website.
