Background:

  • Slug/snail control is estimated to cost WA grains industry$1.86 million dollars per annum
  • If uncontrolled slug/snail damage is estimated to cost $19.25 million dollars in lost yield
  • Surveys conducted in Western Australia in 2013 showed the small conical snail was more wide spread and more difficult to control than slugs or round snails.
  • Snail/slug control on sandy soils in the Albany Port Zone is restricted to baiting alone. This reliance on baiting does not give complete control of slug/snail populations because:
    • Immature snails do not readily feed on baits
    • Timing of applications at seeding does not necessarily coincide with slug/snail activity
    • Cultural control option of burning is not considered viable due to soil erosion

Scope of work:

There is a need for more cultural control options rather than wide-scale burning for the control of small conical snails.

  • Tillage has not been trialled, even in South Australia (according to Greg Baker entomologist based at SARDI), for the control of small conical snails. In conjunction with Derk Bakker as part of GRDC project DAW00204:  ‘Delivering enhanced agronomic strategies for improved crop performance on water repellent soils in WA’ one tillage trial will be conducted on a paddock with high snail densities. Paddock will be chosen in conjunction with the Stirlings to Coast Farmers. It is proposed that this research project will monitor the effectiveness of the tillage for the control of small conical snails on sandy soils.
  • Weed control and snail control will be integrated into one post-harvest trial on the effectiveness of chaff windrow burning to manage small conical snail populations over an entire paddock. Growers are reluctant to conduct a wide scale burn due to soil erosion concerns. One trial will be to monitor the effectiveness of windrow chaff burning as a management tool for small conical snails.
  • Results from trials will be disseminated by: one paper in an appropriate format, one talk at a field day in the Albany port zone, one talk on radio, one media release.

There are some concerns that the reason bait applications have not been effective for the control of slugs has been due to the timing. Baits need to be applied when slugs are actively moving but when there is limited green plant material. Growers in the Stirlings to Coast Farmers and South Dirt groups have reported that bait applications post seeding, pre-crop emergence controlled germinated.

  • In conjunction with SARDI, as part of GRDC project‘DAS00134: Improved snails and slug management’,   proposed that this project will set up and monitor monthly one time lapse camera to assist in the prediction of environmental factors that trigger movement and feeding for slugs.  Camera will be set up in a paddock with a history of slug damage as determined by members of the Stirlings to Coast group. Working with DAS00134 will lead to southern Western Australian environmental conditions feeding into models being developed as part of DAS00134. This will give Western Australian growers better tools to predict when slugs will be active on their properties to better time baiting applications. Western Australia has different cropping rotations, stubble retention and soil types to South Australia which may influence slug emergence.

Expected outcomes:

  • Better understanding of how cultural controls for the management of small conical snails can be applied on sandy soil types
  • Feeding of Western Australian data into models being produced on slug movement will ensure the model predictions will be apply to Western Australia
  • Increased extension and dissemination of control methodologies for slugs and snails