How to Manage Pests
Pests in Gardens and Landscapes
Adult gall midges are tiny, delicate flies, often with long
slender antennae. They resemble fungus gnats and flies
in certain other families. Larvae are tiny yellow to
orange maggots that can't be seen unless you cut the galls
open. There are hundreds of species of gall midges, not all
of them pests. Each
gall-forming species is specialized to feed on only one or
a few closely related hosts. Some common pests
of flowers and ornamentals include the chrysanthemum gall
midge, the violet gall midge, and the honeylocust
pod gall midge. Other species of gall midges prey on
aphids and are beneficial.
In gall-making species, larvae bore into tissue or cause tissue to form into galls that surround the larvae, which feed inside. Galls are distorted and sometimes colorful swellings in plant tissue.
For flowers in planting beds, clip off galls
and distorted plant parts as soon as you see them, and remove
them from the garden. If you have a severe infestation,
you may want to remove all susceptible plants. Gall midges
are difficult to control with insecticides.
Adult honeylocust pod gall midge
Female violet gall midge on curled violet leaf