Petiolegall and Vagabond Gall Aphids

    Petiolegall and Vagabond Gall Aphids

    Pemphigus spp.; Mordwilkoja vagabunda

    poplar spiral gall aphids

    Poplar spiral gall aphids (Milan Zubrik, Forest Research Institute - Slovakia,

    petiole galls

    Galls on petiole of leaves produced by poplar petiolegall aphids (Herbert A. 'Joe' Pase III, Texas A&M Forest Service,

    vagabond gall aphids

    Leaf galls produced by vagabond gall aphids (Minnesota Department of Natural Resources,

    Pest Description

    Petiolegall Aphid

    • small, 1/13 inch; pale green; covered in a waxy film; with or without wings
    • recognized by round galls on Populus spp. petioles

    Vagabond Gall Aphid

    • very small, 1/50 – 9/50 inch; color variable; with or without wings
    • recognized by galls noticeable after leaf fall

    Host Plants, Diet & Damage

    Petiolegall Aphid

    • creates round galls on cottonwood, poplar and aspen petioles; damage primarily aesthetic

    Vagabond Gall Aphid

    • creates unsightly galls on cottonwood and aspen; damage primarily aesthetic

    Biology, Life Cycle & Damaging Life Stage

    • form galls by feeding on host tissue
    • adults and immatures cause damage
    • overwinter as eggs within galls or in bark crevices
    • eggs hatch in spring as foliage expands, forming galls
    • alternate to a summer host around mid-summer once galls have dried out
    • return to host in fall to lay overwintering eggs

    IPM Recommendations

    • Little negative effect on tree health; tolerate pest.
    • Keep trees healthy and stress free.
    • Apply horticultural oils to overwintering eggs in spring prior to budbreak.
    • Once galls form, insecticide cover sprays will not be effective.
    • Apply a systemic insecticide (neonicitinoid) in the spring.