There was limited snail activity across Victoria, South Australia and southern New South Wales in the long dry autumn of 2025.
Moderate conditions and late rain in spring is thought to have aided survival and breeding of conical snails, with high levels of small (less than 2 mm) individuals detected in grain samples. Conical snail numbers were not reduced in lentils sprayed with carbendazim, however an application of Metarex Inov Snail and Slug Bait1 reduced the population significantly, highlighting its efficacy.
Substantial rainfall in March 2026 has now triggered extensive snail activity in these regions. Applying Metarex Inov now will provide you excellent control of Italian and vineyard (round) snails prior to their breeding. You should focus on known areas, along fence lines and water channels/creek lines, where high numbers are known to seek refuge over summer.
A cluster of snails on a grapevine trunk
This should catch populations before they spread out into paddocks to feed on the new vegetation. It is essential to monitor snail numbers after application and assess if re-application is needed.
Slug control
According to a GRDC monitoring project2, there was limited, late emergence of black keeled slugs in 2025, hence limited slug damage to canola. Proactive growers applied bait after seeding to protect seed and seedlings. Where bran-based pellets were used, some growers needed to re-apply after substantial rainfall. Those using Metarex Inov were controlling slugs, even after 50 to 80 mm of rain, five weeks after application.
In traditional slug areas, large numbers of grey field slugs were observed in late November 2025 when windrowing crops. Based on previous experience that means, if it rains after sowing, slugs will be present in May 2026. Observations and research support the hypothesis that slugs become active once soil moisture is greater than 25 to 30 per cent.
A grey field slug with it's baby on the leaf of wheat
Additionally, black keeled slugs can delay breeding for over 500 days. This highlights that you can't be complacent. Use long-lasting Metarex Inov for sustained control; especially where monitoring of establishing crops every 3 to 4 days is not possible.
In summary
- Understand when slugs and snails are actively feeding and breeding, as this underpins successful management.
- Applications of Metarex Inov® now, following substantial rainfall in March, will reduce round snail numbers this autumn. Rolling after harvest prior to bait application complements that control.
- Protect susceptible seed/seedlings by applying Metarex Inov after sowing and before crop emergence.
References:
1.Metarex Inov ® is a registered trademark of De Sangosse SA.
2. GRDC monitoring project UOA2308-004RTX
This article was written by Dr Michael Nash from AgNova Technologies for Seasons magazine.
