Fruit IPM for July 26, 2019

Peach:

Oriental Fruit Moth: Treatments for the 3^rd generation OFM are timed for now in northern counties. Treatments are done in southern counties.

For later generations from this point forward, it is more reliable to rely on trap captures. If trap captures exceed 6 moths per trap, then treatments are justified for the 4^th generation and any overlapping generations (in southern counties at the present time). See timings in the table below:

Brown Rot: Most growers should be relying on a captan based program for mid-season covers, followed by better materials during the last 3 weeks pre harvest.Do not spray captan or sulfur if temperatures are above 85-90 deg F. and do not combine captan with sulfur in hot weather with poor drying conditions. See Dr. Norm Lalancette’s recent article in the Plant and Pest advisory for more information on pre harvest brown rot programs.

San Jose Scale: San Jose Scale crawlers have emerged in southern counties. See previous posts for control options. Emergence will continue and peak in early August.

Apple:

Rots/Summer Diseases: Various rots are starting to show up on the fruit. Early indications are that both Honeycrisp and Empire can be seen with small bitter rot lesions starting to form. These varieties seem to be particularly susceptible to bitter rot. Research being done in Dr. Kari Peter’s lab in Biglerville, PA is showing that Omega @ 6.9 fl oz/A when applied in July can be part of an effective program. Omega has a 28 day PHI, so be careful on the varieties where you use it. Omega (fluazinam) can be used at up to 13.8 fl oz/A and has a maximum total application restriction of 8.625 pt/A/season or 10 applications. Rotate the Omega with Captan (0 days PHI) at up to 5 lb/A of 80W (max total – 40 lb/season), or at up to 6-8 lb/A of 50W (max total –  64 lb/season). When you get closer to harvest, Merivon (FRAC 7+11)(0 days PHI) can be alternated with Captan, but Merivon probably should be used for the last 2 consecutive applications just prior to harvest. Merivon can be used up to 4 times per season at a maximum rate of 5.5 fl oz/A or a total of 22 fl. oz. per A per season. Dr. Peter’s lab is finding that Luna Sensation, which is also a FRAC 7+11 chemistry, and has bitter rot on the label, is not effective for bitter rot in our area. As previously mentioned, there are a number of sanitary practices that should always be done that help in general rot control: 1) Remove infected fruit before harvest, 2) Where dead shoots are present from fire blight, prune them out to reduce inoculum buildup; and 3) Maintain good coverage with sufficient water volume for all sprays.

Codling Moth (CM): The timings are updated below for third generation CM. Trap counts are starting to come up, but are below 5 males per trap on most farms. All second generation treatments have been applied, which has been indicative of an early season. The next flight coming up is for the third generation. This is often drawn out in recent years, and therefore traps counts and thresholds should be considered along with the initial model timing. Growers in southern counties should plan on initially treating during the first week of August if trap captures exceed 5 males per trap.

Grapes:

Vineyards are approaching bunch closure in southern counties. This time is important for disease control. See a recent blogpost from Dr. Nita at Virginia Tech for more information.

Grape Root Borer (GRB): IF you have a problem with grape borer in your vineyard, and IF you did not use mating disruption earlier in the season, then the bases of the vines should be treated now. Previous surveys have shown that only 30-33% of NJ vineyards have GRB populations that justify treatment. The ONLY WAY to determine if you need to treat is to monitor the pupal cases that are left at the base of the vine as the adult emerges from the roots. Trap captures over the past week show an increase in adult emergence. Those adults will now mate and lay eggs at the base of the grape vine.

Grape Trap Counts

Tree  Fruit Trap Counts – Southern Counties

Tree  Fruit Trap Counts – Northern Counties

Blueberry

Spotted Wing Drosophila (SWD): For the past 3-4 weeks our traps have shown a marked increase in adult activity.  Elliott and other late varieties are still being harvested, and the SWD population is even higher this week than it was last week. DO NOT let up on your program, and keep to a 7 day program. We have done very well this season, but no buyer wants the extra protein in their fruit!

Putnam Scale: We have seen a slight uptick in scale activity this past week. This may be the start of the second crawler generation. If you kept track of which fields had 1^st generation scale issues, then you may want to plan on treating over the next couple of weeks.

Oriental Beetle (OB): Adult activity is decreasing. All treatments for this insect should have already been applied. From this point forward in the season, any additional treatments are purely ‘Revenge Sprays,’ and will not work since the larvae are too big to be controlled.

Aphids: Aphid infestations have decreased since last week, showing an average of 1.8% of terminal infested. This is a very low level, and indicates that aphids are no longer an issue to deal with.

Blueberry Traps

Atlantic County Traps

Burlington County Traps