Plum, flowering (Prunus)-Hop aphid

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

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Management-chemical control

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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.