Buxus – Boxwood Leaf Miner and Psyllid
The following pictures show two infections on the same Boxwood plants.
The cupped foliage is due to the feeding by Psylla buxi - Boxwood Psyllid bugs.
The yellow to beige discoloring of the foliage is a different problem caused by the feeding by Monarthropalpusi flavus - Boxwood Leaf Minor midges.

Both may be controlled with Acephate applied in April. Apply every year in April thereafter to maintain healthy beautiful foliage.
This may be applied as a drench poured right over the plants or with a low volume end-of-hose sprayer sprayed over the plants. 
Acephate is the active ingredient in Bonide Systemic Insect Control
Please follow the instructions on the container.

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