Pasture / Winter Crops – Redlegged Earth Mite; RLEM (𝘏𝘢𝘭𝘰𝘵𝘺𝘥𝘦𝘶𝘴 𝘥𝘦𝘴𝘵𝘳𝘶𝘤𝘵𝘰𝘳)

Crop:         Pasture / Winter Crops
Insect(s): Redlegged Earth Mite; RLEM (Halotydeus destructor)

Guidelines:

1. Rotate insecticide Groups.
2. Do not apply consecutive sprays of products from any one insecticide Group.

*Refer: CropLife Australia Expert Committee on Insecticide Resistance Mode of Action Classification for Insecticides

3. If both autumn and spring applications are needed, alternate chemical groups.
4. Timing of sprays:
5. Monitor RLEM activity carefully and only treat if damage has reached threshold levels. Hatch timing tool can be used to determine season risk.¹
6. One well timed spray in Autumn or Spring will maximise effectiveness of treatment. Optimal timing of Spring sprays can be calculated using the TIMERITE tool.²
7. 1. Placement of sprays:
   2. Apply perimeter sprays where infestations are concentrated on the edge of the fields.
   3. Use blanket sprays where appropriate. However, with pyrethroid products, recent research has shown that the risk of pyrethroid resistance can be minimised through the application of foliar pyrethroids in a 50 m strip with 10 m spacing.³
   4. Cultural practices:
   5. Heavy grazing or cutting for hay or cultivation will reduce mite numbers.
   6. Control alternative hosts such as Capeweed and Paterson’s curse.
   7. Develop damage thresholds.
   8. Rotate crop and pastures that are more tolerant to the pest.
   9. Encourage predator survival by judicious use of insecticides.

   For more detail on resistance management for RLEM in grain crops and pastures, refer to: https://grdc.com.au/resources-and-publications/all-publications/publications/2020/redlegged-earth-mite-best-management-practice-guide-southern

   Notes regarding the application of insecticides:

   1. To ensure the most effective control of the pest:
   2. Product labels should at all times be carefully read and adhered to;
   3. Full recommended rates of registered insecticides should always be used; and
   4. Ensure good coverage of the target area to maximise contact.

   References

   1. Hatch timing tool developed by Cesar to aid with early season monitoring and predict RLEM risk at crop establishment https://cesaraustralia.com/pestfacts/new-redlegged-earth-mite-hatch-timing-tool/
   2. TIMERITE tool TimeRite (wool.com)

   ^3. Strip spraying delays pyrethroid resistance in the redlegged earth mite, Halotydeus destructor: a novel refuge strategy – Maino – 2021 – Pest Management Science – Wiley Online Library