CRAPEMYRTLE APHID
The
crapemyrtle aphid is sometimes a pest of crape myrtles. This tiny insect
feeds by inserting slender mouthparts into leaves and sucking out sap that
is rich in sugars. As they feed, aphids also inject saliva. This saliva causes
pale yellow spots on the leaves. Overall plant vigor may suffer. Leaves may
become distorted later as they develop. Crapemyrtle are slow, fragile insects
that vary from 1/16 to 1/8 inch long. They are pale yellowish green with black
spots on the abdomen.
Winged adults have dark tipped antennae and two double-pronged humps on the back. Young crape myrtle aphids resemble wingless adults although they are smaller.
Crapemyrtle
aphids were first discovered in Hawaii, though they are now known wherever
crapemyrtles are grown. These aphids excrete a sweet, sticky liquid called
honeydew. When aphid numbers are large, honeydew often completely coats
leaves and other objects below, giving infested plants a sticky or varnished
appearance. Honeydew attracts ants, flies wasps and other insects. Black,
unsightly fungi called sooty mold often develops in honeydew, further disfiguring
plants.
Crapemyrtle
aphids overwinter in the egg stage. The eggs hatch in April, and for the
rest of the growing season crape myrtle aphids give birth to living young.
The young aphids mature in about 10 days. There are several generations
per year. Both winged and wingless aphids are born during the growing season.
Winged forms migrate to start new colonies only on crape myrtles. The last
generation of females lay the overwintering eggs.
Natural enemies of crapemyrtle aphids include ladybird beetles and their larvae, green lacewings and their larvae (aphid lions), hover fly maggots, parasitic wasps, and entomophagous fungi. Sometimes these parasites and predators are not able to keep crapemyrtle aphids under control, so chemical control may be desired. The following sprays are some choices that may be used to control aphids. Insecticidal soaps and horticultural oils will have the least negative impact on beneficial insects. Sometimes two applications of an insecticide at 7- to 10-day intervals are required. Hort oils can also be applied as an early dormant spray post leafdrop. Repeat application when needed as aphids reappear. Some formulations of acephate (Orthene) can be applied as a slurry painted onto the bark of crape myrtle. Follow label directions.
Choose less susceptible
varieties of crape myrtle (PDF).
| Pesticide | (Trade Name) | Formulation |
|---|---|---|
| acephate | (*Orthene) (Orthene TTO) others | contact and systemic |
| *malathion | (Cythion) | 56% emulsifiable conc. |
| fluvalinate | (Mavrik) | 23% aquaeous flowable |
| *horticultural oil | various | |
| imidacloprid | Bayer Advanced Tree & Shrub | systemic |
| *soap, insecticidal | various | |
| bifenthrin | (Talstar) | 10% wettable powder |
| endosulfan | (Thiodan) | 50% wettable powder |
| For More choices | see | NC Agr. Chem. Manual |
Prepared by: James R. Baker & S. Bambara, Extension Entomologists
Published by North Carolina Cooperative Extension Service
Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age, or disability. North Carolina State University at Raleigh, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
ENT/ort-31 April 1994 (Revised) May 1997
Web page last reviewed January, 2008 by the webperson.