Spring Brings Azalea Lace Bugs Out of Hibernation

As another winter turns to spring, bears aren’t the only
things coming out of
hibernation. Azalea lace bugs are waking up, too, and will
soon damage prized azaleas if
homeowners don’t take action.

Azalea lace bugs are the main pests of landscape
azaleas, say University of Georgia
entomologists. The insect with the
beautiful, lacy wings can cause ugly damage to azalea
foliage.

Lace bugs feed on the underside of leaves and extract
the contents of the upper layer
of cells. This causes the azalea leaves to appear bleached
or mottled.

Kris Braman, an entomologist with the UGA College of Agricultural and Environmental Sciences, said early spring is the perfect time to check plants for azalea lace bugs. Controlling them now, while they’re young, is the key, she said. “The azalea lace bug spends the winter as an egg inside your azaleas’ leaves,” Braman said. “Now that the temperatures are warming, the eggs are beginning to hatch. And newly emerged nymphs are beginning to feed.”

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Braman said a properly scheduled insecticide application
will get rid of these nymphs
before they mature and have time to lay eggs.

“If you
don’t kill them before May,
they will have laid eggs, and you’ll have to spray several
times,” she said.

If not controlled, azalea lace bugs can produce four
generations from spring to fall.
“If you kill this first generation,” she said, “you may
not have to spray
again.”

UGA entomologists urge homeowners to use less toxic
insecticides to save the good bugs
in the landscape.

“Using less toxic insecticides allows you to conserve
beneficial insects like the
parasitic wasps and spiders that feed on lace bugs,”
Braman said.

“Horticultural oils and insecticidal soaps have been
around a long time,” she
said. “People are using them more now. But you need to
remember that these are
strictly contact insecticides.”

Contact insecticides must be sprayed on the insects.
They work best on soft-bodied bugs
like aphids and lace bugs.

“They have no residual activity on the leaves,” Braman
said, “So
beneficial insects can walk on that leaf surface, after
the fact, and not be killed. Good
contact with lace bugs on the underside of the leaves is
important for good control.”

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If homeowners don’t spray for azalea lace bugs, Braman said, young plants will suffer the most damage. “In our research,” she said, “we have observed that older plants, those that have been in the landscape for several years, can withstand more lace bug damage. They can tolerate some damage because they have well-established root systems and are not already under stress like a newly transplanted azalea.” Braman said this is one reason homeowners keep replacing young plants year after year.

“If you wait too long to spray, the nymphs
will become egg-laying
adults. And you will have to fight all stages of lace
bugs,” she said.
“Unfortunately, the egg stage is not affected by
insecticides.”