Fruit IPM Update for 5/24/17

Peach

Tufted Apple Budmoth (TABM): The first of 2 flights of tufted apple budmoth have started. Adults started to emerge in northern counties on 5/16 and in southern counties on 5/1. Although this has been a minor pest, timings are outlined below for anyone who had high populations last year.

Plum Curculio (PC): PC egg laying should be nearly complete in all areas of the state. We have accumulated about 380 DD since petal fall (apple) in southern counties and just over 210DD in Hunterdon County. The Cornell model calls for insecticides applied up to the 340DD₅₀ mark. This allows for the last of the PC activity to be covered by the residual from the last insecticide application. It is important to note that we are still seeing some active adults in the Hammonton and Burlington County areas on blueberries and in traps. In southern counties, any PC effective material applied over the next few days should be the last application needed for PC control. After that, it should be safe to switch to materials that target catfacing insects and other tree fruit insects that are active. Treatments in northern counties should still be targeted for PC activity.

Tarnished Plant Bugs and Other Catfacing Insects: This is the key insect complex to target at this time of year. Tarnished plant bugs will become more of an issue as temperatures warm and mowing and other ground cover activities become more common. Most materials, except the diamides (Altacor, Exirel) used for these pests will have some efficacy for plant bugs.

San Jose Scale (SJS): Scale crawlers usually emerge about the first week of June. While it is too early for control, growers may wish to be prepared if you had known high populations of scale last year: If you have scale infestations on your trees, it is important to note if crawlers are present, even if you treated with oil in the early spring. If crawlers are present then treatment options include Esteem, Movento, Centaur, and Diazinon. Esteem, Centaur and Movento should be applied at the beginning of crawler emergence. Diazinon is labeled for only one post bloom or foliar application on stone fruit (Rec = max. of 2 lb/acre of the 50W). The apple label allows up to 2 foliar applications per year as long as a prebloom application was not made. The peach label allows 1 foliar application per year. Foliar applications may cause russet on apples, but has worked in the field for scale crawlers as long as applications are made 1-2 weeks after the start of crawler emergence and again 2 weeks later.

Bacterial Spot: Copper formulations should be maintained in cover sprays to suppress bacterial spot. Generally we recommend starting at 0.5 ozs metallic copper and gradually lowering the rate as the season progresses. The rate applied will depend on the formulation. Dr. Lalancette published a chart listing common copper formulations and rates for peach and nectarine applications. These rates include: Kocide 3000 @ 1.7 oz/A, Cueva @ 25 oz/A, Champ Formula 2 @ 1.4 oz/A, Copper-Count-N @ 5.3 oz/A, and Badge X2 @ 1.8 oz/A. See the link for other rates. Avoid combining copper with captan especially if it has been overcast for several days. Also avoid acidic spray solutions when applying copper. Mycoshield may also be used at 1-1.5#/acre. It is more rainfast than copper but has a short residual. Leaf and fruit symptoms were found in highly susceptible varieties last week in southern counties.

Peach Scab: In addition to Rusty Spot and Bacterial Spot, peach scab requires protective applications at this time. Topsin/Captan or Topsin/Sulfur combinations are general used in cover sprays where scab was a problem last year. Captan or Sulfur alone is sufficient in orchards that were clean last year. Other effective materials include QuadrisTop, Inspire Super, Luna Sensation, Abound and Gem. Do not use Abound in the same sprayer as used on apples.

Rusty Spot: An effective material should be included at petal fall, and continue through 2^nd cover on rusty spot sensitive varieties. Rally at 2.5 – 5 oz./acre is the standard product used in cover sprays. Rusty spot symptoms are now appearing on susceptible varieties.

Anthracnose: Hot and wet weather is favorable for anthracnose infections. The varieties Klondike, Harrow Beauty, Snow Giant, and Sugar Giant seem to be particularly susceptible. Growers may find it useful to protect against anthracnose, especially in blocks that have a history of the disease. For all practical purposes this means avoiding the use of sulfur in those blocks, and substituting Captan (2.5# 80W; 4# 50W) for the next several weeks. Ziram @4.5-8#/ac is also effective. QoI chemistries (Pristine, Luna Sensation, Gem) should also be effective when applied around final swell.

Apple

Codling Moth (CM): The first codling moth flight has started. A biofix was set for CM on April 26 in southern counties, and on May 2 in northern counties.

Tufted Apple Budmoth: See peach section above.

European Apple Sawfly (EAS): This insect will be active into first cover. Adult females lay eggs just under the skin of freshly set fruit, and the young larvae mine just under the skin. If let go, the larvae will cause extensive fruit damage. Where this insect is active, it is a primary target at petal fall. In orchards of mixed variety plantings, the petal fall spray for the entire planting is prolonged. This enables EAS to start damaging the first varieties where petals fell earlier before a petal fall spray could be applied to the entire block. Petal fall treatments should not be delayed, especially in northern counties. Fresh damage was observed in apple blocks in southern counties last week.

Summer Diseases: We are now entering the phase for secondary scab control if primary infections are becoming visible. The primary diseases of concern are the Rots, Sooty Blotch and Fly Speck. Anthracnose (Bitter Rot) has been troublesome over the past few wet seasons especially on Empire and Honeycrisp. If you are using the extended EBDC schedule, control should be good on most cultivars. Where anthracnose control has been difficult to control consider using Pristine, Merivon, or add Captan or Ziram to the program.

Fire Blight: A few orchards have low to moderate levels of strikes present. Sanitation is important both to remove inoculum and to help prevent bitter rot inoculum buildup. Instructions for deciding when and how to cut out fire blight strikes can be found on page 7 of the UMASS bulletin, “An Annual Program for Fire blight Management”.

Pear Psylla : Pear Psylla adults are still laying eggs for the second generation of nymphs. Control of this generation is important to avoid overlapping generations throughout the summer. Scout the growing tips for eggs. Eggs are usually laid along the center leaf rib mostly on the leaf underside. Applications of 1 % summer oil in early cover sprays have shown to be of benefit. Use oils and adjuvants with caution on Asian varieties. When applying insecticides for psylla control timing is important as materials such as Movento and Agrimek should be applied when the first eggs hatch. In the case of Movento application a few days before hatch is better, since this material takes some time to move into the tissue. Add penetrants as per label instructions. Neonicotinoids may also applied when the first eggs hatch. The addition of 1 qt. summer oil or a non-ionic surfactant will improve control with these materials. Finally Sivanto, a chemistry closely related to neonicotinoids is effective but should be used with oil as per label instructions. Some miticides such as Portal and Nexter are effective, but should be applied when most eggs have hatched but before any nymphs begin to form wings.

Scouting Calendar Tree Fruit Southern Counties

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

Key pests and developing pests at this time include plum curculio, cranberry fruitworm and aphids.

Plum curculio (PC): The average number of adults being found in beating trays or our “per bush” sample was 0.017 PC per bush over the last week. While this is lower than the preceding weeks, it also is dependent on temperature and other environmental conditions that were present when the actual monitoring took place. The average number of injured fruit is also declining at .174%. However, PC is still a target to be controlled. The maximum level seen per bush was 0.3 adults, and PC adults are present in the PC traps placed the week of 5/13, with 2.4 adults/trap in Atlantic County and 7 adults/trap in Burlington County. Therefore, any insecticides being applied over the next several days should include a PC effective material.

Cranberry Fruitworm (CBFW): Adult trap capture increased in Atlantic County and decreased some in Burlington County. Overall trap levels are low, and indicate overall low population pressure, although some increases in the Hammonton area were seen during the past couple of days. We are having an early season, and are likely entering the peak time of flight and egg laying activity. Given the early season and fruit stage, this is a pest that should be targeted along with PC (if still present). If controlling both PC and CBFW, remember that the best PC materials will also control CBFW, but the opposite is not true. Imidan and Avaunt also control CBFW, but targeted materials for CBFW like Assail, Delegate, Esteem and Rimon do not touch PC. The pyrethroids ( Bifenture, Brigade, Danitol, Hero, Mustang) will control low populations of PC, but are not ‘high PC pressure materials’. Exirel will control both pests

Aphids: Aphid populations are close to what they were the previous week – averaging about 4% infested shoots, with a maximum of 22%. Overall aphids are not a target, except under a few extreme cases. The neonicotinoid insecticide is the workhorse for aphid control. These include Actara. Assail, and Admire (imidacloprid) (IRAC 4A). Non neonicotinoid materials that also control aphids include Sivanto (IRAC 4D) and Exirel (IRAC 28).

A note for planning the next treatment: If the upcoming treatment is going to be one of your last treatments by ground, remember that that aphid control is best done from the ground. If no PC activity is present, then the main insect targets become cranberry fruitworm and aphids, especially if this is one of the last ground applications. In this case, Assail becomes a product of choice, since it is effective for both aphids and CBFW.

Tree Fruit Trap Counts – Southern Counties

Tree Fruit Trap Counts – Northern Counties