African armyworm (Spodoptera exempta)
The African armyworm is a very damaging pest, capable of destroying entire crops in a matter of weeks. Although they are regarded as occasional pests, in an outbreak large number of caterpillars will appear destroying the whole plant to ground level.
- Monitor regularly field margins, low areas where plants have lodged, beneath plant debris around the base of plants, on the ground, and underneath the plant leaves. Check daily young crops if conditions are known to be favourable to the pest.
- Spray Bt or botanicals such as neem and pyrethrum extracts. Spray when caterpillars are small. Once caterpillars are mature (about 3 to 3.5 cm long) they may have already caused serious damage and it may no longer be economical to treat the crop. For more information on Neem click here, for Pyrethrum click here and for Bt click here
- Conserve and encourage natural enemies. For more information on Natural enemies click here
- Practise field sanitation. For more information on Field sanitation click here