Parasitic wasps
The parasite Aphelinus mali can completely control aerial colonies of the woolly apple aphid. Populations
of this parasite often increase rapidly in fall after the effects of summer spraying have diminished.
When monitoring aphids, examine the colonies to determine the level of parasitization; parasitized aphids
are black and may have an exit hole from which a parasite emerged. | 
Blackened
aphid bodies are parasitized
|
