Monitor egg hatch by late April, using a hand lens (15x). Aphids have two distinct forms: stem mother is relatively large and bluish-gray; offspring is smaller, greenish-yellow, and may be covered by a fine powdery wax.
Scout for pale tan, oval eggs coated with wax.
Use beating sheet or board to detect presence of adults.
Listen for wasps and bees.
Check for black soot on the ground.
Encourage natural predators like lacewings, earwigs, lady beetles and their larvae, ants, predatory thrips, predaceous midges, and parasitoids such as Aphidius spp.
Apply insecticide after eggs hatch. Synthetic pyrethroids may cause outbreak of secondary pests, such as eriophyid mites, due to reduction of natural predators.