Volume 57 Number 12 Date 06/28/2012
CODLING MOTH - The first flight has declined at some locations and continued at others. The summer flight of moths should begin in the next 1-2 weeks. Apple growers are advised to check their records for the spring biofix to estimate the second biofix, which generally occurs 1,000 degree days (base 50°F) later in a typical year. Approximately 750-950 degree days have accumulated since the first biofix on May 3-4 or 12. In preparation for the summer flight, growers should replace pheromone lures and begin more frequent trap checks.
APPLE MAGGOT - Emergence has increased in some apple orchards, while others have not yet captured a single fly. The high count for the period of June 21-27 was seven flies on a baited red ball trap at Plymouth in Sheboygan County. On the basis of current degree day accumulations, peak emergence of the fly population should occur from July 7-21 at most sites.
SPOTTED TENTIFORM LEAFMINER - The second flight continued, with pheromone trap counts ranging as high as 962-1,600 moth per trap at Beldenville, Hillpoint and Rio. The peak in flight activity is expected by the first week of July throughout southern and central Wisconsin and a week or more later in the east-central and northern areas. Egg laying is likely to be very heavy as long as the moths are numerous. Apple orchards with populations greater than one mine per leaf or a history of infestation are candidates for control of second generation leafminer larvae.
--Krista Hamilton, DATCP Entomologist