Phorodon humuli
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Pest description and crop damage Soft-body, bluish green insect found on the underside of leaves or in rolled leaves. Heavy infestations cause severe defoliation.
Management- biological control
See:
Biological Control of Nursery Pests
Management-chemical control
See:
Chemical Control of Nursery Pests
It is important to cover foliage thoroughly, including lower leaf surfaces. Difficult to control unless applications are made in early spring before leaves are rolled. Apply oils in dormant or delayed-dormant periods.