Controlling mice
Mice damage has been reported in areas across north west Victoria in crops which appear from the drivers seat of the ute to be doing very well. Mice have the potential to cause significant damage and therefore yield loss. Therefore we need to be out of our utes, in the paddock closely monitoring. Use the following information to help you develop a management plan.
How many mice are on your farm?
Early detection is the key to preventing crop damage. The first step is to gauge numbers in all paddocks. Two ways you can do this are:
- Walk in a straight line for 100 metres and count the number of active holes within 1 metre width. To find out whether mice holes are active, circle holes with talcum powder. The next morning walk the transect again counting the number of holes where the powder has been disturbed. Two active holes per 100 metre transect is enough to warrant baiting. Five active holes per 100 metres can mean as many as 10 mice per 100m2, equivalent to 1,000 mice per hectare (1ha = 10,000m2).
- Peg 10 x 10cm paper squares soaked in canola oil at ground level at 10 metre intervals across a transect. Check cards the next morning for damage. 10% or more of the canola card area eaten is enough to warrant baiting.
So you’ve got mice. Now what?
Mouse Off® (zinc phosphide) bait can be spread via aerial or ground application at a rate of 1kg/ha and will provide good protection against mice damage. It can be spread in stubble, pasture and crop, or a vegetative fallow but shouldn’t be applied to bare ground. Continue to monitor paddocks after baiting including those that didn’t require baiting. Mouse Off has a withholding period of 14 days, therefore it can be used if mice are still present and causing damage during grain fill.
Good farm hygiene will help prevent mice problems. Clean up grain spills, set the harvester to minimise grain loss and reduce cover around buildings, silos and hay sheds. Bromadiolone or brodifacoum baits (such as Talon®), can be used in bait stations around sheds. Farmers with hay stored for export should be particularly vigilant.
For more information regarding the control of mice see What constitutes a mouse problem? (PDF - 200KB) MOUSEOFF® Zinc Phosphide Bait (PDF - 842KB) and On-going control of mice or visit http://www.animalcontrol.com.au/
Also see: http://www.bcg.org.au/cb_pages/controlling_mice_at_sowing.php