PestFacts south-eastern This season has already seen widespread infestations of Bryobia mites, however, control measures have not always been necessary.
Where have they been reported?
Following on from reports in PestFacts Issue No. 1 there has been numerous reports of Bryobia mite this season extending from the northern Mallee of Victoria (Ouyen-Pinaroo and east of Manangatang); North East Victoria, southern Riverina (Jindera), up into the Central West Slopes & Plains of NSW (Orange) and across to the Central Tablelands of NSW (Cowra).
Reports have come from several crops and pastures, including canola, wheat, lupins, lentils, vetch and clover pastures.
In several cases growers are choosing to use insecticide because infestations are severe and plants are in their early stages.
However, in many cases crops are able to tolerate moderate infestations of Bryobia mites.
About this pest
For detailed information on Bryobia mites, including their occurrence, lifecycle, behaviour, damage symptoms and management strategies, go to Bryobia mites.
Our advice
It is important to distinguish Bryobia mites (Bryobia spp.) from other mite species before deciding on control options.
Inspect paddocks during the warmer parts of the day. Look for mites and evidence of feeding damage on newly established crops and pastures.
Established crops can tolerate moderate infestations of Bryobia mites and it is likely that Bryobia numbers will naturally decline in most areas with the onset of cooler late autumn and winter conditions.
Some insecticides are registered for Bryobia mites, however, be aware that recommended rates used against other mites might be ineffective against Bryobia mites.
Bryobia mites have a natural tolerance to several chemicals; we have received numerous reports of chemical control failures involving Bryobia mites when growers have sprayed insecticides, especially alpha-cypermethrin.
Insecticides do not kill mite eggs.
Generally organophosphate insecticides provide better control against Bryobia mites than synthetic pyrethroids.
Acknowledgements
Sources of field reports of Bryobia mites
Josh Douglas – Researcher, The University of Melbourne
Andrew McMahen – Agronomist, Landmark (Victorian Mallee)
Bob Ronald – Agronomist, Landmark (North East Victoria)
Mitchell Small – Agronomist, Elders (NSW Central Tablelands)
Matthew Witney – Agronomist, Dodgshun Medlin consultants (Victorian Mallee)
Cover image: Photo by Andrew Weeks, Cesar Australia
