WNC Orchard Insect Populations for June 26, 2018
Little has changed since last week in higher elevation orchards such as Henderson County (>2000 ft). At about 1100 DD from biofix, we remain between flights of the first and second codling moth generations. In addition, oriental fruit moth populations remain low throughout the area, and first generation tufted apple bud moth flight is complete. European red mite, leafhoppers and aphids remain the key potential pests at this time.
In lower elevation orchards such as Cleveland and Lincoln Counties, second generation codling moths are beginning to emerge. Codling moth DD accumulations since biofix in Cleveland County is about 1380, and first sprays for second generation flight are recommended at 1400 to 1450, depending on codling moth pressure. In orchards with low pheromone trap captures and no damage from the first generation, a single application shortly after 1500 DD is usually sufficient.
Now is a good time to keep an eye out for Japanese beetles, especially on young trees, as high numbers of them have been noted in some locations. Most neonicotinoids will do a good job knocking down Japanese beetle numbers without flaring European red mite populations.
Brown marmorated stink bug populations remain low throughout the region. Currently, overwintered adults are declining in numbers and nymphs are in early stages of development – second or third instars.
Learn more about southeastern apple insect pests at the Apple Insect Management page.
2018 Average Weekly Trap Captures*
|Insects per trap|
|Oriental Fruit Moth||16.0||15.7||19.3|
|Tufted Apple Bud Moth||1.0||1.0||0.0|
|Brown Marmorated Stink Bug (commercial – mountains)||1.5||0.5||0.4|
|Brown Marmorated Stink Bug (commercial – upper piedmont)||0.7||1.0||0.6|
|Brown Marmorated Stink Bug (research – unsprayed)||2.5||2.3||0.8|
|Spotted Tentiform Leafminer||40.0||12.0||30.0|
|Lesser Peachtree Borer||42.5||15.0||13.5|
|San Jose Scale||7.5||12.5||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||797||936||1124|
|Oriental Fruit Moth||Apr 2||1249||1418||1636|
|Tufted Apple Bud Moth||May 4||929||1099||1317|
|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: