There are 30 species of beneficial carabid beetles in the UK, each with a particular weed or pest benefit.
However, separating each carabid species can be tricky so Rothamsted Research has created a guide. This doesn’t just offer guidance on species identification but also their particular farm benefit, dispersal, behaviour and habitat.
The key ID features flowchart groups species by size, colour and shape which then allows users to identify specific species through more detailed information. There is also advice on trapping.
But Rothamsted is looking to refine this further. It wants farmers to get involved in the Carabid Monitoring Programme. “We want to understand more on their behaviour and lifecycle and then design approaches how growers can attract greater carabid diversity and get them where needed,” says Rothamsted entomologist Dr Jowett.
Rothamsted wants farmers to monitor carabids in field margins, adjacent field areas and field centres. That’s because a recent study has questioned the effectiveness of field margins. “I don’t want to underplay the importance of field margins but we looked at various margin options to evaluate the impact on carabid diversity. Rather than confirm our hypothesis that higher density would be found in field margins and 5m adjacent field area, greater abundance was found in field centres.
“What we need to do now is look at in-field interventions that can support carabid populations. We’ve found that undersowing oats with grass/clover mix supports beetles and larvae and that the surface chaff through reduced tillage benefits the snail and slug hunting species. The more data we can collect covering an array of farming practices and systems will help significantly.”
