In this section:
Burning & Baiting
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Burning is very effective at reducing high densities of snails but increases the risk of soil erosion. It is a good initial control method in situations where there are high snail numbers. For example, when a paddock comes out of pasture and goes into a cropping phase. Research has found that a hot and even burn is important for good snail control. Poor snail control occurs when there are unburnt patches, resulting in a poor snail kill. |
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Burning works best when:
Burning is less effective against conical snails as they tend to hide under rocks and summer weeds. Cabling just prior to burning or fire harrowing will improve control. |
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Soil Erosion and BurningBurning stubble has positive and negative impacts. It can destroy stubble born diseases and kill weed seeds, but it can also cause erosion and reduce organic matter. Burning must be avoided on soils which are prone to erosion. All these factors need to be considered before burning. Where snail populations are large, a strategic burn, perhaps once every 3-4 years, will dramatically increase the success of managing snail numbers with baits. |
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Baiting
When to bait?
Baiting should commence following an autumn rain and when there is sufficient moisture/ over- night dew for snails to remain active for 2-3 days following the bait application. Killing mature snails before autumn egg laying significantly reduces the potential for populations to build up in that season. Bait degrades in UV-light so it should be spread immediately before or just after there is enough moisture over the two to three days to stimulate snail movement.
Round snails less then 7mm in diameter and conicals less than 7mm in length, which are usually present from late winter onwards, are unlikely to be controlled with baits.
All baiting must be stopped by the end of August or two months before harvest to ensure bait has broken down and does not become a contaminant of grain. Windrowed crops should not be baited. There is zero tolerance for bait contamination of grain.
Baits are not registered for use in pastures so all baiting should be focussed in cropping paddocks. Stock must not be grazed on stubbles that have been baited. Use baiting as part of an integrated management strategy for control of snails.
Why monitor snail numbers?
Snail numbers should be monitored to assess the need to bait and to determine the bait rate to use. Seven days after baiting a second count should be taken to identify the effectiveness of the control and determine the need for further bait applications.
Growers should monitor through the growing season to check for reinvasion. Multiple bait applications may be required during the winter but this need must be based on monitoring results.
Bait fence lines throughout the season to combat reinvasion of snails into the edges of the paddock. For round snails increase the rate of bait if snail numbers are above 80/m2 (snails > 7mm).
Fence posts and roadside vegetation etc are popular sites for aestivating snails. This makes the area adjacent to the fence a ‘high traffic area’ for snails following the autumn rains. Repeated baiting in these areas can result in a high level of snail mortality.
Bait rates
| Snail | Snails/ m2 over 7mm | Kg bait required / ha |
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| Round snails | Less then 80/m2 | 5 kg/ha |
| Over 80/m2 | 8-10 kg/ha | |
| Conical Snails | No threshold established | 5kg/ha |
Which snail bait?
There are about 10 snail baits commercially available in Australia. These are retailed under different brand names but contain one of three active ingredients: metaldehyde, methiocarb and Fe-EDTA. No significant differences in mortality have been observed between the three active ingredients. Currently choice of baits comes down to which products are registered for use in your state and price. Always consult the label before application.
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Active Ingredient |
Mode of Action |
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| 15g/kg metaldehyde | Irritant, which causes excess mucus secretion and desiccation; inhibition of mobility; nerve poison at high concentration. |
| 20g/kg methiocarb | Inhibits nervous system |
| 60g/kg Fe-EDTA | Stomach Poison |
