Woolly apple aphid - monitoring

There are three key occasions for monitoring woolly apple aphid in IFP:

Summer monitoring:   This determines insecticide use in summer.
Harvest monitoring:   This determines insecticide use at green tip next season.
Post-harvest monitoring:   This determines post-harvest insecticide use (for high populations)
and, if the threshold is exceeded, also indicates the need for control
at green tip in the following season.

Organic production - Woolly apple aphid does not usually require monitoring in an organic orchard because the pest is well controlled by natural enemies. If this is not the case, the cause of disruption of biological control needs to be tracked down and changed.