Description of the Pest
Light brown apple moth, also known as LBAM, is an exotic pest native to Australia that has been detected in coastal California from Los Angeles to Sonoma counties.
In both appearance and behavior, the light brown apple moth is similar to other leafroller species in the tortricid family that occur in grapevines. The mature larval stages are pale-to-medium green with a light yellow-tan head. The first segment behind the head (prothoracic shield) is greenish brown with no dark markings. Full-grown larvae are about ½ to ¾ inch (10 to 18 mm) long. However, larvae cannot be reliably identified using morphological characters. Take captured, suspect larvae (preferably alive) to the county agricultural commissioner's office for proper identification.
The most efficient and reliable method for trapping male adults is with the use of light brown apple moth pheromone traps. There are many native tortricids that can be confused with this pest. Tortricid moths hold their wings over their abdomens in a bell shape when at rest and have protruding mouthparts that resemble a snout. Many moths have oblique markings on the wings. If you find a tortricid moth in a light brown apple moth pheromone trap, take it to your county agricultural commissioner's office for positive identification.
Depending on the climate, this pest may have from 2 to 4 generations a year. In its native range it does not survive well at high temperatures, but it does thrive in cooler areas with mild summers, moderate rainfall, and moderate-to-high humidity. Overwintering larvae do not have a winter resting stage (diapause). During the winter second- to fourth-stage larvae can be found on vegetation surrounding vineyards, on weeds or in grape mummies on the vine. Larvae may survive for up to 2 months in the winter without feeding.
Adult moths emerge after 1 to 3 weeks of pupation and mate soon after emergence. They stay sheltered in the foliage during the day, resting on leaf undersides. Females begin to lay eggs 2 to 3 days after emerging, depositing them at night on the upper side of leaves. On grapevines, eggs are normally found on fully developed leaves near the edge of the leaf blade. The eggs are typically laid in masses of 20 to 50 (but may contain up to 170 eggs), slightly overlapping each other like fish scales. Egg masses are covered with a greenish transparent coating when newly laid, but the eggs become darker as the embryo develops. Larvae emerge after 1 to 2 weeks and disperse widely on the vine. In spring the first stage larvae move to shoot tips where they web together developing leaves to form nests. The larvae feed within these shelters. Larvae may enter fruit clusters as early as bloomtime. They produce webbing along the cluster stem tying flower parts together and feed on developing berries in a manner similar to omnivorous leafroller and orange tortrix.
Damage
Overwintering larvae may feed on buds; injured buds may fail to develop further. During bloom, larvae may feed on flower clusters. After veraison, feeding damage to the berries may allow rot organisms to infect fruit.
Management
Removing mummified fruit and overwintering sites under the vines can reduce populations of these leafrollers. Well-timed spray treatments with a selective insecticide may be warranted if moths are caught in pheromone traps placed inside the vineyard and light brown apple moth larvae are seen feeding on grape clusters.
Biological Control
General insect predators and several species of spiders may influence these leafroller populations by feeding on eggs or larvae. High mortality has been reported during the initial dispersal of the newly hatched larvae. Several parasitic wasps, Meteorus sp. in particular, have been recorded parasitizing light brown apple moth in California.
Cultural Control
Appropriate sanitation practices during the dormant season can help prevent a buildup of these leafrollers. Mow broad-leaved weeds in and around the vineyard before bud break. Remove mummified clusters when pruning and place them in the row middles to be chopped.
Organically Acceptable Methods
Cultural control and sprays of Bacillus thuringiensis and the Entrust formulation of spinosad are acceptable for use on organically certified crops.
Monitoring and Treatment Decisions
Pheromone lures are commercially available and may be used to monitor the presence of these moths in the vineyard.
In early spring, monitor shoots for webbing of leaves and larvae inside their nests. Follow the monitoring procedures in MONITORING CATERPILLARS, which have been developed for other vineyard leafrollers. Look for rolled leaves that appear glued to shoots. Beginning at bloom, monitor bunches for webbing and larvae. If insecticide applications are warranted, they must be applied before bunch closure.
Pesticides and Natural Enemy Releases
Not all registered pesticides are listed. The following are ranked by their IPM value, with the most effective and least harmful to natural enemies, honey bees, and the environment listed at the top of the table. When choosing a pesticide, consider information related to water and air quality, resistance management, and the pesticide's properties and application timing. Use PestManage to compare summarized management options for different pests in the same crop. Always carefully read the label of the product being used and take all necessary precautions when handling pesticides.
| Rank | Active ingredient | Example trade name | Group | Group Order | MoA 1 | Amount per acre | REI (hours) ‡ | PHI (days) ‡ | Comments | Selectivity 2 | Bees 3 | Predatory mites 4 | Predators 5 | Parasitoids 5 | Residue duration 6 | Leaching(fish) 7 | Adsorbed runoff(fish) 8 | Solution runoff(human) 9 | Leaching(human) 10 | Solution runoff(human) 11 | Last updated 12 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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|
various products # | Bloom to Bunch Closure | 4 |
11A |
Label rates | 4 | 0 | Most effective on young larvae. | narrow | low | low | low | none | — | — | — | — | — | 07/2015 | ||
|
|
Altacor | Bloom to Bunch Closure | 4 |
28 |
2.0–4.5 oz | 4 | 14 | — | narrow | low | low | low/moderate | short | — | — | — | — | — | 07/2015 | ||
|
|
Intrepid 2F | Bloom to Bunch Closure | 4 |
18 |
10–16 fl oz | 4 | 30 | Do not apply more than 48 fl oz/acre per... | narrow | low | low | low | none | very low | low | low | very low | low | 07/2015 | ||
|
|
Delegate WG | Bloom to Bunch Closure | 4 |
5 |
3–5 oz | 4 | 7 | A stomach poison; most effective when in... | narrow | low/moderate | moderate 13 | moderate/high | moderate 14 | low | low | low | very low | low | 07/2015 | ||
|
|
Entrust # | Bloom to Bunch Closure | 4 |
5 |
1.25–2 oz | 4 | 7 | Do not apply more than 7.5 oz of Entrust... | narrow | low | moderate 13 | low/moderate | short | very low | low | low | very low | low | 07/2015 | ||
|
|
Success | Bloom to Bunch Closure | 4 |
5 |
4–6 oz | 4 | 7 | Do not apply more than 29 fl oz of Succe... | narrow | low | moderate 13 | low/moderate | short | very low | low | low | very low | low | 07/2015 |
Legend
- ‡ a b Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without personal protective equipment. Preharvest interval (PHI) is the number of days from treatment to harvest. In some cases, the REI exceeds the PHI. The longer of the two intervals is the minimum time that must elapse before harvest.
- # a b Acceptable for use on certified organic crops. Check with your certifier to confirm before application.
- 1 ↩ Group numbers for insecticides and miticides are assigned by the Insecticide Resistance Action Committee (IRAC). Insecticides with unknown modes of action are assigned mode-of-action group numbers (MoAs) that begin with UN. Rotate pesticides 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; insecticides with a 1B group number should be alternated with insecticides that have a group number other than 1B.
- 2 ↩ Range of insect and mite groups affected by a pesticide. Broad means the pesticide affects most groups of insects and mites; narrow means the pesticide affects only a few specific groups.
- 3 ↩ Risk of harm to honey bees. For more information, see Bee Precaution Pesticide Ratings.
- 4 ↩ Risk of harm to predatory mites. Toxicities are generally to western predatory mite, Galendromus occidentalis. Where differences have been measured in toxicity of the pesticide-resistant strain versus the native strain, these are listed as pesticide-resistant strain or native strain.
- 5 a b Risk of harm to parasitoids and general predators. Toxicities are averages of reported effects and should be used only as a general guide. Actual toxicity of a specific insecticide depends on factors including the application rate, environmental conditions, and the life stage and species of a parasitoid or predator.
- 6 ↩ Length of time residue affects natural enemies. Short means hours to days; moderate means days to 2 weeks; and long means many weeks or months.
- 7 ↩ Risk of harm to fish from leaching, based on USDA Natural Resources Conservation Service Windows Pesticide Screening Tool (WIN-PST).
- 8 ↩ Risk of harm to fish from adsorbed runoff, based on USDA Natural Resources Conservation Service Windows Pesticide Screening Tool (WIN-PST).
- 9 ↩ Risk of harm to fish from solution runoff, based on USDA Natural Resources Conservation Service Windows Pesticide Screening Tool (WIN-PST).
- 10 ↩ Risk of harm to humans from leaching, based on USDA Natural Resources Conservation Service Windows Pesticide Screening Tool (WIN-PST).
- 11 ↩ Risk of harm to humans from solution runoff, based on USDA Natural Resources Conservation Service Windows Pesticide Screening Tool (WIN-PST).
- 12 ↩ Date information was last updated in the UC IPM Pest Management Guidelines.
- 13 a b c Toxic to some natural enemies (lacewing and syrphid fly larvae, predatory beetles, and thrips) when sprayed and up to 5 to 7 days after.
- 14 ↩ Residual is moderate if solution is between a pH of 7 and 8.
UC IPM Pest Management Guidelines: Grape
UC ANR Publication 3448
L.G. Varela (emeritus), UC IPM and UC Cooperative Extension Sonoma County
D.R. Haviland, UC IPM and UC Cooperative Extension Kern County
W.J. Bentley (emeritus), UC IPM and Kearney Agricultural Research and Extension Center, Parlier
L.J. Bettiga, UC Cooperative Extension Monterey County
K.M. Daane, Kearney Agricultural Research and Extension Center, Parlier
R.J. Smith (emeritus), UC Cooperative Extension Sonoma County
L.R. Wunderlich, UC Cooperative Extension Central Sierra
F.G. Zalom (emeritus), Entomology, UC Davis
Acknowledgement for Contributions to Invertebrates
M.C. Battany, UC Cooperative Extension San Luis Obispo County
J. Granett (emeritus), Entomology, UC Davis
P.A. Phillips (emeritus), UC Cooperative Extension Ventura County
A.H. Purcell (emeritus), Environmental Science, Policy, and Management, UC Berkeley
