Weekly Insect Bytes
Unless noted otherwise, the insect pest control updates presented below are for the south-central part of Pennsylvania based on observation in Adams County, PA.
Current insect pest updates:
Ø First generation Oriental fruit moth flight is continuing across the state. While in Erie County this week is a good time to control hatching larvae for the first time this season, in the southern counties the second application of effective products should be applied already. In Adams County, the OFM egg hatch reached about 70 percent (as of May 17) and it is a last call for an effective control of this OFM generation.
Ø Plum curculio adults will need to be controlled for at least another two weeks. The cooler weather so far suppressed the pressure from PC adults, but the forecasted warm and humid conditions will create perfect circumstances for PC feeding and oviposition. Appropriate, effective insecticides should be applied based on orchard monitoring and documented pest control needs.
Ø In southern part of Pennsylvania, codling moth adults are active and, if needed, the first codling moth treatment should be planned sometime during the week of May 26th. Applications of Altacor®, Belt®, Delegate®, Tourismo® or Voliam Flexi® or Voliam Xpress® should provide excellent control of CM. Codling moth granulosis virus (Cyd-X®, or Cyd-X HP) applied after the beginning of egg hatch should also provide good control of CM neonate larvae.
Ø If hand applied mating disruption materials (Isomate® or CheckMate® products) are planned for the control of CM, OFM, dogwood borer, peach tree borer and lesser peach tree borer, the dispensers should be already placed in the orchards. For a maximum efficacy of mating disruption products, dispensers for all mentioned species should be placed as high within the tree canopy, as it is possible, preferably within the top 10 percent of the canopy.
Ø Scale insects can still be controlled with an application of Esteem® or Centaur® with an addition of low rate of oil or application(s) of Movento®. The secret to good scale control is good coverage. Growers should use a minimum of 100 GPA or more depending on the size of their trees.
Ø Although not very common, the green peach aphid colonies are being observed in some peach and nectarine orchards. A threshold of one colony per nectarine tree or five colonies per peach tree is recommended in Pennsylvania. Watch for predator populations such as ladybird beetles or syrphid fly larvae. The presence of predators in about one out of five aphid colonies may lead to successful biological control.
Ø Brown marmorated stink bug is continuing its movement away from overwintering shelters and feeding on multiple species of plants, most likely not inside orchards. In majority of orchards no special stink bug control activities are required at this time. Visual search for BMSB adults still remains the only reliable monitoring technique at this time of the season.
Ø All pheromone traps for monitoring fruit insect pests should be already placed in orchards. The 2013 season biofix for the Oriental fruit moth was established on April 17; spotted tentiform leafminer on April 09, codling moth on May 06, tufted apple bud moth on May 09. Obliquebanded leafroller adults are still not active (as of May 17).
Prepared by Dr. Greg Krawczyk PSU Department of Entomology, Fruit Research and Extension Center, Biglerville, PA.