Ash Plant Bug

    Ash Plant Bug

    Tropidosteptes spp.

    ash plant bug

    Ash plant bug (University of Minnesota)

    ash plant bug damage

    Ash plant bug damage (Whitney Cranshaw, Colorado State University, Bugwood.org)

    ash plant bug damage

    Ash plant bug damage (Whitney Cranshaw, Colorado State University, Bugwood.org)

    Pest Description

    • adults: 3/8 inch; pale yellow, brown to black; yellowish-green triangle on back between wings
    • nymphs: similar in appearance but are smaller, ovoid, wingless and may vary in color
    • eggs: oblong and laid on bark or undersides of leaves

    Host Plants, Diet & Damage

    • ash
    • feed on sap of ash leaves
    • white stippling on top of leaves; wilting, curling, stunted and drying leaves
    • brown to black fecal spots on damaged leaves
    • browning leaves and leaf drop later in the season
    • most damage occurs on young foliage in late-May

    Biology, Life Cycle & Damaging Life Stage

    • overwinter as eggs near buds or within bark fissures
    • egg hatch begins in late-April to mid-May
    • first generation develops into adults and eggs are laid in June on leaf midribs
    • second generation feeds from July until frost
    • second generation eggs laid in late summer and fall
    • two generations per year
    • nymphs and adults are the damaging stages

    IPM Recommendations

    • Manage trees to improve or maintain health.
    • Damage is mostly aesthetic; tolerate pest.
    • Ash plant bugs on young or nursery trees may require management.
    • Apply an insecticide (carbamate; insecticidal soap; pyrethroid) about 1 week after budbreak to manage young first generation nymphs. Target the undersides of foliage.