Volume 57 Number 18 Date 08/16/2012
SPOTTED WING DROSOPHILA - Fly emergence is expected to intensify next month and continue through October or early November. Research has shown that SWD is most active in mid- to late summer and that daily high temperatures in the 70s are ideal for reproduction and growth. Fruit growers concerned about this pest should place vinegar traps now and report any suspects to Krista Hamilton at DATCP. Spotted wing drosophila was detected for the first time in the state in October 2010 and has been found in Crawford, Dane and Racine counties since then.
CODLING MOTH - Low to moderate flights were registered at several monitoring locations in the past week, indicating that codling moth pressure has not diminished in all areas. High counts of 13-19 moths per trap were reported from Oneida and Chippewa Falls.
STINK BUG - Nymphs and adults are very active in field crops and may become abundant in orchards just before harvest. The feeding and probing by both nymphs and adults results in visible injury, posing an economic risk to maturing fruits. A single adult or nymph in the orchard can potentially damage many apples. If the feeding occurs just prior to harvest, depressions on the fruit surface may not develop until after a period of time in storage. Scouting is strongly advised at this time. The highest numbers usually occur on the edges of orchards bordering woods or agronomic crops.
SPOTTED TENTIFORM LEAFMINER - The third and last flight of the season has peaked and is now declining at most orchards. Trap counts ranged from 10-432 moths from August 9-15, with the high count registered at Hillpoint in Richland County. Moth activity should continue throughout the month and subside by mid-September.
--Krista Hamilton, DATCP Entomologist