Fruit IPM Report for 5/9/2013

• Peach
• Apple
• Scouting Calendar
• Blueberry
• Trap Counts

Peach

Oriental Fruit Moth (OFM): Oriental Fruit Moth (OFM): As of 5/6 we have accumulated 322 DD base 45 in southern counties. In northern counties 117 DD have accumulated. Based on the current forecast, the first of two applications for OFM should be made between 5/10 and 5/12 in northern counties. The OFM target for the second application at 350-375 DD in southern counties is late this week 5/9-11. Growers who wish to deploy mating disruption for OFM have an additional choice this year with respect to timing. If using the Biocontrol hand applied product, the new TT dispensers last a longer period of time. Therefore, they can be placed in the orchard any time now and before the second flight starts. If you are planning to use sprayable pheromone, then you must still wait until the end of the first OFM flight.

Green Peach Aphid (GPA): Aphid colonies are now visible in some orchards in southern counties. see the 4/13 IPM Report for more information.

Plum Curculio (PC): PC activity is very low at present in southern counties. See last week’s report for control information.

Lesser Peachtree Borer (LPTB): Adults should start flying soon. Growers who wish to employ mating disruption for lesser borer control should begin placing dispensers in orchards during the next week or two.

Peach Fungal Diseases: Weather conditions so far have been favorable for rusty spot, however the current pattern is favoring scab. To date constriction canker is the only fungal disease exhibiting symptoms.  Some orchards with leaf curl have been seen in southern counties.  Bravo (only permitted through shuck split) has been very effective for leaf curl control. However the usual practice assumes that nothing can be done for leaf curl once leaf tissue emerges and picks up the pathogen from surrounding bud scales.

Bacterial Spot: Fruit at this stage is very susceptible to bacterial spot. Favorable conditions for epidemics include persistent winds along with heavy rains or long periods of moisture or humidity. This is an important time for control. Coppers or Terramycin should be applied anytime wet and windy weather is expected. Bacterial spot lesions from the wetting period on 4/29 have been seen on on the leaves of highly susceptible varieties in southern counties. Leaf symptoms appear about a week after infection, while fruit symptoms appear about 3 weeks after infection.

Special Warning on Phytotoxicity: Be very careful when tank mixing Captan and coppers. Captan/copper combinations should be avoided after long periods of overcast skies, since we have previously experienced moderate to severe phytoxicity following several days of cloudy weather. Also be careful with buffering solutions in tank mixes. Copper injury can occur with acidic mixtures.

Apple

Codling Moth (CM):  A Biofix for CM was set in southern counties on Sunday May 5.  Timing for the first of 2 sprays for the 1^st generation is set at 250 to 350DD₅₀ and again at 14 to 21 days later or around 550DD for the standard insecticides – OPs, carbamates, pyrethroids, neonicotinoids, spinosyns and  Delegate, and the granulosis virus. Granulosis virus is a biorational control marketed under the names Carpovirusine, Cyd-x and others. These products are useful as a supplement to mating disruption, or for resistance management. The timings for the IGR Rimon is at 75-100DD, and the IGR’s Intrepid, and Esteem are at 100-150DD and again at 450DD. As of 5/6 we have accumulated 5 DD base 50 in southern counties. Based on the forecast we should reach 75 DD on or about 5/13 if using Rimon, but the first spray using standard materials won’t be due until the 3^rd week of May. The 2^nd complete spray timing for CM often coincides with timings for tufted apple bud moth.

The newer diamide chemistries (Altacor, Voliam Flexi/Xpress, Belt, and Tourismo) are other options for codling moth and internal worm control. These materials have long residuals and are highly effective. Some growers find that using Delegate for first generation CM control and then a diamide combination for the second generation works well, since the chemistry has a long residual and the summer generation is typically spread out over a long time period.

Apple Scab, Powdery Mildew (PM) and Cedar Apple Rust (CAR): Overwintering ascospores are now 99% mature in southern counties as of 5/6. In northern counties spore maturity is at 67%.  Primary scab infections are present in a few blocks in southern counties. Since wetting periods started in Wed. 5/8 and are predicted to continue through the weekend, significant scab infections can occur. Temperatures are predicted to be in the 70’s during these periods so infections can be severe. Make sure to be covered before the rain, and keep an accurate record of the precipitation amounts on your farm. Fungicides have different properties when it comes to “reach back activity” redistribution and rainfastness.  See  the enclosed table from the Cornell Crop and Pest Management Guidelines:
http://ipmguidelines.org/TreeFruits/Chapters/CH06/default-1.aspx

Table 6.1.3. Characteristics of Apple Scab Fungicides

[1] Not effective against resistant strains of the fungus.
[2] The after-infection activity of Sovran and Flint may be only 48 hr in orchards with resistant populations of apple scab.
[3] Apples are not included on the most recent label.
[4] Given the wide spread prevalence of fungicide resistance in regional populations of apple scab, one should not rely on post-infection activity.
§ Potentially acceptable in certified organic programs.
Key: P = poor, F = fair, G = good, VG = very good, E = excellent.

For a complete set of resistance management recommendations, see the April 12 article by Norman LaLancette.

Powdery Mildew and Cedar Apple Rust: Mildew and rust infections are still possible so maintain coverage with effective materials.

Fire Blight: Blossom sprays using antibiotics should be applied anytime temperatures are 65° F or above and the relative humidity is 60% or above even where most bloom is over. The current weather pattern is very favorable for infection in all regions of the state. Check the NEWA site for local predictions.  Apogee has been used with success for fire blight suppression. When streptomycin is applied six days after an Apogee application, research has shown suppression is significantly increased over Apogee use alone.

Petal Fall Pest Complex: Plum.Curculio and European Apple Sawfly are targets at petal fall. Growers also should evaluate rosy aphid control before making petal fall applications. Rosy aphid infestations have been seen in southern counties. Where rosy’s need treatment, Assail and Calypso will control the entire complex in addition to white apple leafhopper and spirea aphid if present.

Scouting Calendar Southern Counties Tree Fruit

The following table is intended as an aid for orchard scouting. It should not be used to time pesticide applications. Median dates for pest events and crop phenology are displayed. These dates are compiled from observations made since 1995 in Gloucester County. Events in northern New Jersey should occur 7-10 days later.

Blueberry:

Plum Curculio (PC): About 3% of total samples have been positive for adults. This is a similar level as was seen last week. Activity should increase with the warmer temperatures predicted for this weekend.

Aphids: Shoot samples are being done to detect aphid presence.  The first aphid was seen on 5/6 and the highest level seen this past week was 2% of new shoots infested. An infested shoot is defined by new growing shoots infested with one or more colonies, with a colony being one aphid or more. Only single aphids have been seen so far. During these early stages of development, searches should be done on the lowest shoot terminals. This is also where Lep/worm larvae are more likely to show up.

Leps (Leafrollers and Spanworms): Leafrollers and Spanworms – About 6% of beating tray samples have been positive for worms. These include gypsy moth and sawfly larvae.  We began shoot samples on 5/6 and as of 5/7 have not seen any larvae in these observations. With respect to adult flights, the first generation redbanded leafroller adult flight is just beyond the peak in Atlantic and Burlington counties.

Cranberry Weevil (CBW): Very little activity is being seen now that bushes are in bloom. Although there are some positive samples, adults are rare in beating tray samples.

Thrips: This pest has recently been seen in traps at low numbers, however sampling of flowers has not shown any presence yet.  In previous seasons we have seen very high trap levels without any significant flower infestation.

Cranberry Fruitworm (CBFW): The first adult moth was seen in our traps on 5/7 in Atlantic Co. CBFW has one generation per year with an adult flight peak usually at the end of May to beginning of June. Insecticides that target CBFW will be applied around that time. More on this later.

Tree Fruit Trap Counts – Southern Counties

Tree  Fruit Trap Counts – Northern Counties

Blueberry Insect Trap Counts – Atlantic County

Blueberry Insect Trap Counts – Burlington County