Silage Advice

Why is soil contamination an issue?

If the silage has an ash content above 10% DM it is a good indicator of soil contamination. Soil is a good source of enterobacteria, clostridia and listeria which increases the risk of a poor fermentation, especially with wetter forages, and can lead to animal health issues.


The risk is highest in wet weather and with lodged crops. If there is a risk of soil contamination, wilt to at least 30% DM and/or use an additive to increase the rate of fermentation.

Minimising soil contamination:

  • Fix muddy gateways
  • Trap moles and roll the fields before mowing
  • Avoid handling the grass in wet weather
  • Increase the cutting height
  • Avoid running machinery over the cut grass
  • Ensure tedders and rakes are set high enough
  • Clean clamp machinery, especially wheels, before you start
  • Keep the clamp apron clean – don’t allow field machinery and clamp machinery to run over the same area

Are you a farmer making grass or maize silage?

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