WNC Orchard Insect Populations for May 30, 2018
The recent heavy rain has significantly suppressed insect activity. Trap captures for most insects were fairly low this week. However, when sunshine and warm weather return, you can expect the insect world to return to normal rather quickly. So for the next week, the insects of greatest concern are codling moth and tufted apple bud moth.
Depending on location, degree-day (DD) accumulations for codling moth range from about 530 in Henderson County to almost 700 in Cleveland County. If you are uncertain of your codling moth population, you should assume that codling moth will remain a threat for the next two weeks in Henderson County. Off the mountain, populations are nearing the end of the first generation flight, and the window for first generation control will close within in the next week.
Tufted apple bud moth DD accumulations range from about 660 in Henderson County to about 870 in Cleveland County, although TABM is generally not an issue outside of Henderson County. An insecticide effective against TABM during the next week should control the first generation. Regardless of whether one is using Altacor or Delegate for first generation codling moth, both products are excellent against TABM. If codling moth control is not required at this time, other options for excellent TABM control are Intrepid and Rimon, as well as the premix products Voliam Flexi, Besiege, Cormoran, and Minecto Pro.
The Comstock mealy bug is a sporadic pest that is most common in Polk County; rarely is it a problem in other apple producing locations in NC. In those areas where this insect has a history of infesting the calyx end of fruit, now is the time for insecticide applications targeting this pest. There are not a lot of insecticides effective against this mealy bug, the most effective being Assail (or premixes containing acetamiprid) or Movento.
Finally, European red mite continues to be observed in more orchards than usual for this time of the year. With the rains letting up, expect ERM populations to continue to build up.
Learn more about southeastern apple insect pests at the Apple Insect Management page.
2018 Average Weekly Trap Captures*
|Insects per trap|
|Oriental Fruit Moth||6.7||4.3||5.7|
|Tufted Apple Bud Moth||6.0||12.0||12.0|
|Brown Marmorated Stink Bug (commercial – mountains)||n/a||2.7||1.3|
|Brown Marmorated Stink Bug (commercial – upper piedmont)||n/a||0.7||3.7|
|Brown Marmorated Stink Bug (research – unsprayed)||0.5||2.2||0.3|
|Spotted Tentiform Leafminer||0.0||0.0||0.0|
|Lesser Peachtree Borer||98.0||47.0||25.0|
|San Jose Scale||0.0||0.0||0.0|
*Note that averages presented here are intended only to illustrate the timing of insect emergence and fluctuations in population activity, and not as general indicators of population levels. Some orchards included in these averages have significantly higher or lower populations than most commercial orchards in the area, resulting in averages that are sometimes skewed from what is typical. The only way to have an accurate assessment of an individual orchard’s populations is to set up traps in that orchard.
2018 Accumulated Degree Days
|Codling Moth||Apr 30||196||358||501|
|Oriental Fruit Moth||Apr 2||503||706||883|
|Tufted Apple Bud Moth||May 4||184||386||564|
|About degree-day models: The degree day (DD) models predict adult emergence and egg hatch of each generation. They do not predict the intensity of populations, which can be assessed by using pheromone traps. Hence, the models should be used to help gauge the time period when control is most likely needed, and pheromone traps provide information on the need for and frequency of insecticide applications. For full details, read “IPM Practices for Selected Pests” in the Orchard Management Guide.|
ORIENTAL FRUIT MOTH:
TUFTED APPLE BUD MOTH: