Honeylocust Plant Bug

Scientific Name: Diaphnocoris chlorionis

Honeylocust plant bugs cause damage by their feeding. When they penetrate cells of the leaf with their mouth parts (stylets), they inject saliva, which aids in digestion and uptake of the plant cell contents. The saliva destroys cells, causing leaf curling, distortion, and in severe cases leaf death. Fortunately, this pest is easily controlled with systemic and topical insecticides. Damaged leaves will remain on the tree after the plant bugs are gone. Foliage must be examined for active infestation before treatment is implemented.

Attacks: Honeylocust (Gledistia tricanthos) all varieties; Black Locust (Robinia pseudoacacia) all varieties

What you will see:

Yellowish white spots “stippling” on leaves
Large brown areas on leaf
Leaf drop and/or deformation of the leaf
Small black spots on bottom side of leaf
Very active green nymphs in May

Life cycle:

Eggs overwinter in twigs and branches
Eggs hatch shortly after the buds open in the spring
Nymphs feed for the next 3-4 weeks until they mature
Adults mate and lay eggs which hatch the following spring

Cultural Management of Honeylocust Plant Bug

Cultural practices:

Increase nectar sources for predators by planting flowering plants nearby
Fertilize according to Arborist recommendation
Mulch with POM® if recommended by Arborist

Chemical practices:

Honeylocust plant bug is susceptible to both systemic and topical insecticides