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Fruits
Volume 59 Number 17 Date 08/28/2014 CODLING MOTH - Counts remain high for late August. The weekly average based on reports from 19 orchards was above-threshold at seven moths per trap, with a range of 1-23 per trap. The peak of the second flight has occurred at most locations, but additional treatments may be required before harvest if the moths remain numerous. Pheromone traps should be checked until 1,700 degree days (modified base 50°F) have accumulated from the first biofix, at which time approximately 90% of second-flight adults will have emerged. BROWN MARMORATED STINK BUG - Fruit growers are advised to watch for this pest next month and in October as the bugs swarm on warm fall days in search of protected, overwintering sites. Brown marmorated stink bug is thought to be established at very low levels in Dane and Jefferson counties, although it has never been detected in any fruit, vegetable or field crop anywhere in the state. Similar to the multicolored Asian lady beetle and boxelder bug, BMSB aggregates on the exteriors of buildings on warm fall days in search of protected, overwintering sites. Any swarms of stink bugs noticed this fall should be reported to DATCP at 1-866-440-7523. SPOTTED WING DROSOPHILA - Larvae and adult flies have been confirmed in 14 Wisconsin counties as of August 28, although infestations are undoubtedly more widespread. This insect poses a serious risk to ripening fruit again this year, making it imperative for growers with SWD infestations to continue treatments every 4-5 days through harvest. A list of insecticide options can be found on the UW-Madison SWD website at http://labs.russell.wisc.edu/swd/management-2/. For organic operations, the OMFI-approved insecticides PyGanic and Entrust are available for SWD control. APPLE MAGGOT - Fly activity has persisted with the recent wet weather, and enough adults are still present in some orchards to cause problems in late cultivars. Counts ranged as high as 24 per trap for the period of August 21-27, with the weekly high capture reported from Niagara in Marinette County. This season's AM flights have been directly correlated to heavy rainfalls of 1-2 inches. Apple growers should continue to monitor AM traps through the first week of September. OBLIQUEBANDED LEAFROLLER - Orchardists are reminded to maintain pheromone traps for this insect throughout September. Second generation larvae occasionally cause severe fruit damage late in the growing season and moth counts in late August and September can be an indication of damage potential by first brood larvae next spring. SPOTTED TENTIFORM LEAFMINER - The third and last flight of the season has peaked and is now declining at most orchards. Moths have been very abundant at some locations during this flight, with a weekly high count of 1,280 moths registered at Hillpoint in Richland County since mid-August. Another larval generation should be anticipated in September based on the trap counts registered in the last two weeks. Apple growers experiencing large numbers of third brood moths may assess infestations by monitoring orchard perimeters for leaf mines. -- Krista Hamilton, DATCP Entomologist 
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