NEW Redlegged earth mite hatch timing tool

A few weeks ago, we sent out an article with the predicted hatch dates for redlegged earth mites calculated using our egg hatch models. Now, we have developed an early-release online tool to allow you to calculate your own hatch dates based on climate data in your local area.

Redlegged earth mite hatch timing tool

Why timing is important

Redlegged earth mite early-season management relies strongly on the timing of hatching of over-summer diapause eggs. Eggs in south-eastern Australia will typically hatch after 5 mm of rain over 5 days, followed by 10 days of mean temperatures below 19 degrees Celsius.

The hatch timing tool uses local weather data (maximum/minimum temperatures and rainfall) to calculate when these conditions will be met and then estimate when redlegged earth mites will hatch in different regions each season.

How to use the tool

The only information you need to use the tool is your location of interest. The tool will then provide the date mite eggs are predicted to hatch for the current year and the hatching probability based on predicted hatch dates across the past 25 years of available data.

We need your reports!

To improve the usefulness and accuracy of our hatch timing tool, we need further validation of the estimates provided by the model. Reports from growers and advisors are an extremely valuable part of this validation.

If you have checked for mites this season, please consider providing your report via this form. It only takes a minute!

Future development

The hatch timing tool can be expanded further. Future additions that could be made include:

  • A user input for irrigation to modify local moisture conditions.
  • Hatch status maps for Australia that show whether RLEM in a region are predicted to be hatched, recently hatched, or unhatched status for the current date.
  • Comparison of current year’s climate against historical so users can intuitively contrast the current year with past years

If you have any feedback about future features, we would love to hear from you. Please let us know, by sending an email to: 

Redlegged earth mite tools webinar


Many thanks to Dr James Maino for the development of the tool, Dr Garry McDonald, Dr Paul Umina and Professor Ary Hoffmann for the development of the model, Dr Paul Umina and Dr Jess Lye for help developing the article and Leo McGrane for the webinar video.

This web tool was developed by Dr James Maino through a GRDC investment (CES2010-001RXT) with contributions from CSIRO, Cesar Australia, the University of Melbourne, and the Department of Primary Industries and Regional Development.

Cover image: Photo by Andrew Weeks, Cesar Australia

What is Pestfacts south-eastern?

PestFacts south-eastern keeps growers and advisers informed about invertebrate pests and beneficials in broadacre crops and pastures during the winter-cropping season in Victoria and southern New South Wales.


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Since 2019 PestFacts south-eastern has been running through IPMforGrains: Best Practice Insect Pest Management, a project delivered by the National Pest Information Network (Cesar Australia, DPIRD, QDAF, NSW DPI, and SARDI). This project aims to provide grain growers and advisors with information on invertebrate grain pest occurrence and equip industry with the knowledge needed to implement integrated pest management practices. This initiative is a GRDC investment and includes in-kind contributions from all project partner organisations.

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