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Weekly Insect Bytes - Timing Optimal for Control of Codling Moth

Posted: May 21, 2015

Codling moth egg hatch is at about 10 percent and Oriental fruit moth egg hatch is at almost 100 percent. The flights of obliquebanded leafroller (OBLR) and peach tree borer (PTB) are expected to start within the next few days. Green peach aphid (GPA) (on stone fruit) and spirea aphid (SA) (on stone and pome fruit) colonies are being observed in some orchards. Watch for predator populations such as ladybird beetles or syrphid fly larvae.
Spirea aphid and syrphid fly larvae predator. Photo by G. Krawczyk.

Spirea aphid and syrphid fly larvae predator. Photo by G. Krawczyk.

Current Pest Status

The insect pest control updates presented below are for South-central Pennsylvania based on observations in Adams County. To view the insect hatch and trapping data for all major insect pests, please visit the Penn State Fruit Research and Extension Center (FREC) website. For control recommendations, refer to the Insect and Mite Control Toolbox.

Codling moth egg hatch at about 10 percent

The codling moth (CM) egg hatch developmental model provided by SkyBit Inc., initiated on May 7th (CM biofix in FREC orchards) forecasts about 10 percent CM egg hatch to occur on May 26th for the Biglerville area. This is an optimal timing to initiate management activities against CM. If mating disruption materials are not used to control this pest, applications of Altacor®, Belt®, Delegate®, Tourismo® or Voliam Flexi® or Voliam Xpress® should provide excellent control. Codling moth granulosis virus (Cyd-X®, Cyd-X HP® or Madex XP®) applied after the beginning of egg hatch should also provide good control of CM neonate larvae.

Green fruitworm a problem in some orchards this year

During this past week at two separate locations (Berks and Bedford Counties) we observed a high number of fruit injured by the green fruitworm larvae. As we described in a recent Fruit Times entomology alert, this pest can cause severe deformation of fruit and injury on foliage. Products recommended for the control of codling moth (except viruses) should also provide excellent control of green fruit worms. Other effective insecticide products include Intrepid and Dipel.

Oriental fruit moth egg hatch at almost 100 percent

Based on the degree-day based developmental model for the Oriental fruit moth (OFM), the hatch of OFM eggs in the Biglerville area should be almost completed by this weekend (forecasted 100 percent OFM egg hatch by May 25th). Products recommended for CM control will also provide excellent control of remaining OFM larvae and some residual activity against tufted apple budmoth (TABM) larvae, which do not need to be controlled for another two weeks. However, it is impossible to control OFM larvae after they are feeding inside growing shoots or apple and peach fruit.

Green peach aphid and spirea aphid colonies being observed in some orchards

Green peach aphid (GPA) (on stone fruit) and spirea aphid (SA) (on stone and pome fruit) colonies are being observed in some orchards. A threshold of one GPA 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.

Brown marmorated stink bug (BMSB) adults observed in traps placed around fruit orchards

We continue to observe brown marmorated stink bug (BMSB) adults in traps placed around fruit orchards. Traps baited with one of the two most common lures: Stink Bug Xtra Combo (from Ag-Bio,Inc.) and Stink Bug Rescue lure (Sterling International, Inc.) and placed on the edges of orchards bordering woods are most likely to capture BMSB adults. As we continue to control the wide spectrum of other fruit pests, in most orchards no special treatment against BMSB should be necessary. However, if juvenile BMSB stages (nymphs) are detected inside orchards, a specific insecticide application targeting BMSB is warranted.

Last call to place borer pheromone dispensers in orchards

If hand applied mating disruption materials are still planned for the control of dogwood borer (DWB) (Isomate® DWB) or peach tree borer (Isomate® PTB Dual) it is the last call to place pheromone dispensers in orchards. As the DWB flight already started any further delay of placing these hand applied dispensers will hinder the efficacy of both products by missing the early portion of the population.

Biofix dates - flights of obliquebanded leafroller and peach tree borer expected to start within the next few days

In the Biglerville area (Penn State Fruit Research and Extension Center [FREC] orchards) the 2015 season biofix for Oriental fruit moth was established on April 26; spotted tentiform leafminer on April 12, codling moth on May 07 and tufted apple bud moth on May 10. All pheromone traps for monitoring fruit pests should already be placed in orchards. The flights of obliquebanded leafroller (OBLR) and peach tree borer (PTB) are expected to start within the next few days.

Contact Information

Grzegorz (Greg) Krawczyk
  • Extension Tree Fruit Entomologist
Email:
Phone: 717-677-6116