Current Western NC Orchard Pest Populations Aug 24, 2015
We track local insect populations throughout the growing season using a system of traps, temperature-recording devices, and degree-day models. Traps and weather data are checked weekly, with results updated by Tuesday afternoon from April through September. Learn more about southeastern apple pests at the Apple Pest Management page.
AUGUST 24, 2015
Codling moth and oriental fruit moth remained relatively low during the past week. With the possible exception of OFM in some orchards that have not used mating disruption, this trend is expected to continue into September. It is uncommon for insect problems to suddenly appear in September in orchards that have not experienced at least some lepidopteran damage by this point in the year. As mentioned in previous weeks, the exception can be OFM. In orchards not using mating disruption, an application of sprayable OFM pheromone in mid to late August usually works as well or better than insecticides.
Apple Maggot. Trap captures in abandoned orchards were low during the past week, and populations are probably on the decline at this point in the season.
Brown Marmorated Stink Bug. BMSB captures in pheromone traps located in apple orchards in Henderson County have been relatively low, and little stink bug damage has been observed on apples. However, the situation may be quite different in hotspots in other locations, so there is no substitute for monitoring for damage in your own orchards, especially in the first few rows adjacent to woods.
Average Weekly Trap Captures*
|Insects per trap|
|Oriental Fruit Moth
|Tufted Apple Bud Moth||3.0||5.0||1.0|
|Brown Marmorated Stink Bug||0.5||0.5||0.3|
|Spotted Tentiform Leafminer||18.0||8.0||21.0|
|Lesser Peachtree Borer||28.5||57.0||35.5|
|San Jose Scale||325.0||512.5||1035.5|
*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.
Accumulated Degree Days
|Codling Moth||April 23||2184||2331||2500|
|Oriental Fruit Moth||Apr 6||2936||3116||3322|
|Tufted Apple Bud Moth||April 23||2676||2856||3062|
|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: