Description of the Disease
Eyespotted bud moth has become an important pest in organic apple orchards in coastal areas but is not a problem in the interior valleys. Larvae are dull brown caterpillars with a shiny black head. Adult moths are gray and similar in appearance to a codling moth but smaller and with a white band across the mid-section. In California, two generations per year have been observed. Adults of the overwintering generation appear in May and lay eggs, which hatch in late June and July. Larvae feed on leaves and the surface of fruits throughout summer. The summer generation adults emerge in September and October. It is believed that the larvae produced by the summer generation overwinter in hibernacula. These larvae emerge in late winter, pupate in spring, and emerge as adults in May. The life cycle and damage from eyespotted budmoth is similar to the apple pandemis moth, and they may co-exist in the same orchard.
Larvae feed primarily on emerging buds and leaves in spring. They roll leaves later in spring and pupate in these leaf rolls. The leaf rolls often contain a dead leaf in the center.
Larvae of the summer generation feed on leaves; the first sign of egg hatch is often windowpaning of leaves where small areas are chewed out leaving just a web of veins. Check with a hand lens for the presence of the small brown larvae in windowpaned areas. Larvae also attach leaves to the fruit with silk and feed on the fruit under the attached leaf, making individual, shallow feeding marks.
Eyespotted bud moth is primarily a pest in organic apple orchards where pheromone mating disruption for codling moth control is used. In conventional orchards, synthetic pesticides applied for other pests easily control eyespotted budmoth. This insect has become a pest in organic apple orchards only in recent years, and effective control measures are still being evaluated. Monitor eyespotted bud moth flights with pheromone traps, which should be placed in the orchard by May 1. Maintain traps through the growing season. Treatments may be warranted in organic apple orchards.
|Common name||Amount per acre**||REI‡||PHI‡|
|(Example trade name)||(conc.)||(dilute)||(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.|
|DELAYED DORMANT/PRE-BLOOM AND LATE JUNE/JULY|
|(Entrust)#||2–3 oz||0.67–1 oz||4||7|
|MODE-OF-ACTION GROUP NUMBER1: 5|
|COMMENTS: A maximum of one prebloom spray and two sprays 7 to 10 days apart in late June and July after the first windowpaning is observed is suggested. Do not apply more than 9 oz of Entrust/acre per year. No more than three sprays of Entrust applied for leafrollers are recommended on the label. Alternation with Bacillus thuringiensis may help delay development of resistance. Toxic to bees; do not spray directly or allow to drift onto blooming crops or weeds where bees are foraging.|
|B.||BACILLUS THURINGIENSIS ssp. KURSTAKI#|
|(various products)||Label rates||Label rates||4||0|
|MODE-OF-ACTION GROUP NUMBER1: 11A|
|COMMENTS: A maximum of one prebloom spray and one early bloom spray as well as two sprays 7 to 10 days apart in late June and July after the first windowpaning is observed is suggested. Alternate with Entrust for resistance management. Most effective when applied during warm, dry weather and while larvae are small.|
|**||For concentrate applications, use the amount given in 80 to 100 gal water/acre, or lower if the label allows; for dilute applications, amount is per 100 gal water to be applied in 300 to 400 gal water/acre, according to label.|
|‡||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).|