Insect Bytes for June 02, 2017

The tufted apple bud moth (TABM), obliquebanded leafroller (OBLR) and codling moth (CM) continue their flights in most orchards across Pennsylvania.
Insect Bytes for June 02, 2017 - News


Codling moth male adult in pheromone trap. Photo: G. Krawczyk, Penn State

Tufted Apple Bud Moth (TABM) and Obliquebanded Leafroller (OBLR)

As the emerging TABM and OBLR larvae will start feeding on the foliage and developing fruit, an insecticide application may be necessary to manage these two leafrollers and CM larvae simultaneously. Insecticides such as Altacor®, Delegate®, Exirel ® or Voliam® Flexi should provide excellent control of TABM and OBLR, and also provide effective control of codling moth larvae. According to the model for the Biglerville area, CM egg hatch just reached around 50 percent (June 01) and egg hatch is about 5 percent for TABM and OBLR. While TABM larvae tend to feed on older leaves, the preferred feeding sites for OBLR larvae are usually located at the top of growing terminals. If OBLR is the dominant species in the orchard, applications of insecticides may need to be repeated to protect developing new foliage. On-site monitoring for TABM, OBLR and CM should provide the best guidance for if and how long control treatments against these pests will be necessary.

Codling Moth (CM)

If only CM control is necessary, the organically approved codling moth granulosis virus (Cyd-X® HP, Madex® HP) applied after the beginning of egg hatch and repeated at weekly intervals should provide good control of CM neonate larvae. The Bacillus thuringiensis based products (such as Dipel ®) or Entrust® can be used if CM is not a problem and only the two leafroller species require specific control.

Tufted apple budmoth male and female moths on peach fruit. Photo: G. Krawczyk, Penn State

Green Peach Aphid (GPA) and Spirea Aphid (SA)

Colonies of green peach aphid (GPA) (on stone fruit) and spirea aphid (SA) (on stone and pome fruit) 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. 

Winged spirea aphid female and young aphids on apple foliage. Photo: G. Krawczyk, Penn State

Scale Insects

Scale insects can be controlled with an application of Esteem® or Centaur® with an addition of a low rate of oil or application(s) of Movento®. The secret to good scale control is a good coverage. Growers should use a minimum of 100 gallons per acre (GPA) or more depending on the size of their trees. Pheromone traps are available to monitor flight of San Jose Scale and can be used to properly time the insecticide application.

Dying apple branch due to a severe infestation of San Jose scale. Photo: G. Krawczyk, Penn State

Close-up of apple branch infested by San Jose scale. Photo: G. Krawczyk, Penn State

European Red Mite (ERM)

European red mite populations remain at relatively low levels in most orchards. If ERM control is needed, acaricides such as Acramite®, Apta® (pome fruit only), Envidor®, Portal®, Kanemite®, Nexter® or Zeal®, are registered for mite control and should be considered at this time of the season.

Oriental Fruit Moth (OFM)

No control of Oriental fruit moth is required at this time. OFM larvae are already feeding inside terminals or fruit and control with insecticides will not be effective. The start of the second generation OFM flight and the next potential timing for OFM control is expected in the next two weeks (perhaps around mid-June).

Injuries on peach fruit caused by the Oriental fruit moth larvae. Photo: G. Krawczyk, Penn State

Injuries on apple shoot caused by the Oriental fruit moth larvae. Photo: G. Krawczyk, Penn State

As during the last few seasons, dinotefuran (neonicotinoid, IRAC Group 4A), the active ingredient of insecticides Scorpion® and Venom®, received the EPA Section 18 Emergency Exemption registration for the use on stone and pome fruit in Pennsylvania during the 2017 season for the control of the brown marmorated stink bug (BMSB). Both products have 12 hours of restricted entry interval (REI) and can be used within 3 days of harvest (3 day PHI).

No more than total of two applications of products containing dinotefuran are permitted per season.

The current, 2017 Section 18 Exemption Registration label is necessary for a legal use of mentioned products containing dinotefuran. The 2017 EPA Emergency Exemption Section 18 registration for dinotefuran containing products will expire on October 15, 2017.

In the Biglerville area (Penn State Fruit Research and Extension Center orchards) the 2017 season biofix for Oriental fruit moth was established on April 5th, spotted tentiform leafminer on April 1st, codling moth on April 25th, tufted apple bud moth on May 1st, and obliquebanded leafroller on May 20th.