Description of the Pest
Avocado lace bug (family Tingidae) occurs in parts of the Caribbean, Mexico, and southeastern United States. As of 2006, in California it occurs only in San Diego County. Also known as the camphor lace bug, its only known hosts are various Persea species and the camphor tree (Cinnamomum camphora), which is grown as a landscape ornamental and commercially for its aromatic extracts.
Lace bugs do not feed on fruit. Adults and nymphs feed in groups on the underside of leaves. This sucking pest causes chlorotic blotches on foliage, which become necrotic. Severely damaged leaves may drop prematurely. Defoliation can result in sunburned fruit and wood and stressed trees, reducing subsequent yield.
Adults are about 0.08 inch (2 mm) long oval shaped insects with a dark (black or brownish) head and thorax. Their abdomen, antennae, legs, and wing covers have both dark and light (orangish, yellowish, or white) areas. Nymphs are mostly dark and orangish, resembling the adults without wings. Eggs are laid on leaves within shiny black globs of excrement. Insects develop from egg to adult in about 1 month during warm weather and have several generations a year. All stages can be present throughout the year.
Relatively little is known about this insect in California. Numbers increase during summer. High numbers and severe foliage damage occur in California on some untreated avocado trees. Avocado lace bug is an intermittent pest in Florida on avocado.
An important component of managing avocado lace bug is preventing its spread into uninfested areas.
- Do not move uncertified host material or dirty bins from infested areas.
- Clean bins and other potentially infested equipment and materials before bringing them into groves, as lace bugs may survive and spread on leaf debris.
- Conserve resident natural enemies that prey on lace bugs, including lacewing larvae and predatory thrips. The introduction of natural enemy species is being researched in an effort to provide classical biological control. At least two species of parasitic wasps kill avocado lace bug eggs in Florida, an unidentified species in the family Mymaridae and an Oligosita sp. (Trichogrammatidae).
Do not treat low numbers of lace bugs. If numbers are increasing and are anticipated to cause extensive foliage damage or premature leaf drop, where feasible make a foliar spray of short-persistence contact materials such as oil or pyrethrin. Avoid persistent, broad-spectrum insecticides, which can disrupt biological control of other pests in avocado. Certain systemic insecticides can be very effective and may be available for application through irrigation systems.
Organically Acceptable Methods
Spray pyrethrin (PyGanic) and certain oils in an organically certified crop.
|Common name||Amount per acre||REI‡||PHI‡|
|(Example trade name)||(hours)||(days)|
|Not all registered pesticides are listed. The following are ranked with the pesticides having the greatest IPM value listed first—the most effective and least harmful to natural enemies, honey bees, and the environment are at the top of the table. When choosing a pesticide, consider information relating to air and water quality, resistance management, and the pesticide's properties and application timing. Always read the label of the product being used.|
|A.||NARROW RANGE OIL#||Label rates||4||0|
|MODE OF ACTION: Contact including smothering and barrier effects.|
|COMMENTS: Requires good coverage to be effective. Check with certifier to determine which products are organically acceptable.|
|(Admire Pro)-soil||10.5–14 fl oz||12||6|
|MODE-OF-ACTION GROUP NUMBER1: 4A|
|COMMENTS: Do not exceed 14 fl oz/acre per season. Apply by chemigation through low-pressure drip, trickle, microsprinkler or equivalent equipment. Application may only occur pre-bloom or during bloom period. Post bloom applications are not allowed. Bees shall not be used in avocado treated while avocado is in bloom. Remove bee hives from avocado orchards prior to application. Hives may be returned only after the avocado bloom period has ended.|
|MODE-OF-ACTION GROUP NUMBER1: 3A|
|COMMENTS: Because there is little residual activity, repeat application may be needed in 2 to 3 weeks and control may be only partial.|
|‡||Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.|
|#||Acceptable for use on organically grown produce.|
|1||Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a group number of 1B; chemicals with a 1B group number should be alternated with chemicals that have a Group number other than 1B. Mode-of-action group numbers are assigned by IRAC (Insecticide Resistance Action Committee).|