Upcoming Events | Pest Focus | Trap Catches | Insects

Upcoming Events | Pest Focus | Trap Catches | Insects

Upcoming Events | Pest Focus | Trap Catches | Insects

Upcoming Events | Pest Focus | Trap Catches | Insects

Geneva Predictions:
Roundheaded Appletree Borer & Dogwood Borer
Peak RAB eggs hatch roughly: July 9 to July 28.

Codling Moth
Codling moth development as of July 14: 2nd generation adult emergence at 1% and 1st generation egg hatch at 98%.

Oriental Fruit Moth
2nd generation – second treatment date, if needed: July 17.

Spotted Tentiform Leafminer
Optimum first sample date for 2nd generation STLM sap-feeding mines: July 10.
Optimum second sample date for 2nd generation STLM sap-feeding mines: July 16

Obliquebanded Leafroller (% estimated egg hatch in DD base 43°F after "halfway point" in development of earliest emerging larvae – 720 DD;
90% hatch – 810 DD):

Oriental Fruit Moth (First treatment targeting earliest egg hatch of 2nd generation larvae between 175-200 DD base 45°F after biofix):

[NOTE: Consult our mini expert system for arthropod pest management, the
Apple Pest Degree Day Calculator:
http://www.nysaes.cornell.edu/ipm/specware/newa/appledd.php
Find accumulated degree days between dates with the
Degree Day Calculator:
http://www.nysaes.cornell.edu/ipm/specware/newa/
Powered by the NYS IPM Program’s NEWA weather data and the Baskerville-Emin formula]

Obliquebanded Leafroller
    According to our developmental models, the first summer brood should be closing in on completing its hatch throughout the state this week.  Orchards with historically high OBLR pressure should have received a first application of a suitable material during the first week of July, and this week would be an advisable time to make a second application against the larvae of this brood.  Spintor and Proclaim are appropriate choices, particularly in cases where the larvae are a bit larger, and a B.t. product such as Dipel, or else the IGR Intrepid are also options, but these tend to be more effective when applied against the earlier stages.  If you are applying Delegate to control codling moth and oriental fruit moth, it will also be very effective against OBLR at this time.  Regardless, we have found that this specific spray is the most critical for preventing fruit-feeding damage at harvest, so put this at the top of your list of priorities if OBLR has dogged you in the past.

Apple Maggot
    Trap catches in Geneva and Highland are steadily increasing, owing to rainfall and soil conditions that are ideal for maggot development and adult  emergence. Stings and larval tunneling have been detected in Honeycrisp in the Hudson Valley. If you aren't monitoring in specific orchards and haven't yet applied a protective spray against AM (and aren't using SpinTor for OBLR), prudence would suggest some attention to this pest.  Hanging a few volatile-baited sphere traps on the edge of susceptible plantings can provide a world of insight on when (and whether) immigrating flies are posing a threat.  Growers on a SpinTor program should be somewhere between the first and second spray of this material for leafrollers, which will provide protection against moderate AM pressure.  For those not using OP cover sprays, Assail and Calypso will both provide excellent control of apple maggot as well as internal leps.

Western Flower Thrips
    This once rare pest has more recently been a cause of damage to nectarines and peaches in the Hudson Valley.  Originally limited to western North America, this is now a cosmopolitan species that is a key pest in the greenhouse production of flowers and vegetables.  Apparently, drought conditions and high temperatures encourage damaging populations that can affect stone fruit crops, particularly nectarines and peaches.  The following information is taken from the PA Tree Fruit Production Guide: "...just prior to and during harvest,...adults move from alternate weed or crop hosts to fruit.  [They] feed on the fruit surface in protected sites, such as in the stem end, the suture, under leaves and branches, and between fruit.  Feeding ...results in silver stipling or patches.  Silvering injury is particularly obvious on highly colored varieties.  Because Lannate has a short preharvest interval (4 days), it can be used to control thrips during harvest."  Also, SpinTor can be used within 14 days of harvest.  An application after the first harvest may prevent subsequent losses; however, an additional application may be needed if thrips pressure is severe.

Mites
    European red mite eggs are present on the foliage right now, and with our sultry temperatures, the period from egg deposit to hatch and multiply is a very short one.  A few orchards we have seen are in ERM trouble so far, but also keep in mind the potential for two-spotted mite, which can reach alarming levels in a hurry under high-temperature conditions.  Inspect your leaves using the 5 mite/leaf form on p. 73 of the Recommends, and be aware that two-spot populations increase more quickly than ERM, so be conservative in your interpretations.  Zeal and Kanemite are good options to keep in mind if treatment is needed; Acramite tends to be more effective against TSSM than ERM, and Nexter works better against red mites than it does on two-spots, but the main advice is to get out there and look at your foliage.

Woollies, again
    Just a repeated advisory to check your canopy sites for aerial colonies of woolly apple aphid, which have been multiplying steadily in many orchards.  These are difficult to control at any time (Diazinon, Beleaf, Thionex, and Assail are options), and worse when they've been allowed to proliferate to the 'finger-staining' stage.

    Most farms with a past history of obliquebanded leafroller (OBLR) infestation have had at least one application of an effective insecticide made to trees for their control so far. In the field we’re presently seeing two types of larvae. These include large larvae that have not been treated, or have survived an initial application, or very small, recently hatched larvae that emerged after insecticide residues became ineffective.

    Summer generation OBLR hatch is spread out. Most growers need two or three applications for acceptable control. This year OBLR hatch began on the 19th of June according to the developmental predictive model. Most growers put on an application for OBLR near this date. Growers may not have seen much in the way of OBLR larvae last week, and may not have put on a second application, which would have been made on or after July 3rd.

    In Highland we’ve had 2.4" of rain since the 1st OBLR application. On June 23 we had 0.83" of rain following the 1st OBLR application. We then experienced successive rains totaling 1” for the week.

    If you’ve been seeing OBLR larvae this week, i.e. experienced control failures, there may be causes that can be avoided at the next application. The foremost cause of control failure is the use of reduced rates, by design or by omission, through faulty sprayer calibration. Simply, most insecticides are rate responsive. The label will give a rate range and many lower rates will not provide acceptable control. SpinTor for example was shown to be ineffective at rates below 5 oz/A in blocks with OP resistant larvae.

    Bts, on the other hand, are just as effective at the lower range of their labelled rates. They will wash off more easily in rain events at all rates. They are also quite prone to environmental degradation. However studies conducted by Harvey Reissig have shown that the Bts are very effective against OBLR larvae when used in a 7-day program using low rates.

    A close second reason for control failure is poor coverage. The use of alternate row applications, high winds, or rains that wash off recently applied materials significantly reduce coverage and residue. Alternate row middle applications may provide acceptable control for highly mobile insects such as plum curculio or apple maggot but provide poor coverage for ‘non-mobile’ insects such as the lepidopteran larvae. For OBLR, coverage is critical. Their leaf rolling and webbing habits allow for optimum exclusion from insecticide applications. No matter how big your sprayer is and how many rows you see the plume moving, you simply do not get the material into the canopy with alternate row middle applications. Couple alternate row applications with a low range rate, less than optimum timing, then add 1” of rainfall, and the likelihood of control failure increases dramatically.

    Another factor that will lead to OBLR control failure is timing of insecticide applications. We have been using the flight of the OBLR adult to determine when the eggs they lay will hatch. The developmental predictive model using degree-day accumulations has successfully been used to determine this date. If insecticides are applied and are on the foliage as soon as the first eggs hatch, larvae are at their greatest level of vulnerability and most susceptible to insecticides. Applying insecticides later in this cycle will allow for many of the larvae to assemble shelters of webbed and folded leaves for protection, thus avoiding contact with insecticides.

    Given the hail we’ve experienced throughout the state this season, the use of pyrethroids, for cost savings, is extensive. Under the constant use of any product, insecticide resistance potential increases. Pyrethroids are no exception. They can be more easily metabolized as temperatures increase compared to the OP’s and carbamates. They have been shown to be more effective under cooler conditions in some lepidopteran studies.

    To summarize, the OBLR has caused extensive damage to Hudson Valley fruit over the past ten years. It is a formidable insect pest and not to be taken lightly. It requires aggressive pest management measures to minimize economic losses. We’re observing moderate to high OBLR populations in commercial blocks this season. Scout for webbing and foliage with tattered edges, and break open clusters in varieties prone to OBLR infestation (such as spur Red Delicious, Jonagold, Cortland and Macoun). And, make the next applications as effective as possible by using effective rates with the best coverage possible.

This material is based upon work supported by Smith Lever funds from the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture.  Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

Scaffolds is published weekly from March to September by Cornell University -- NYS Agricultural Experiment Station (Geneva), and Ithaca -- with the assistance of Cornell Cooperative Extension. New York field reports welcomed.  Send submissions by 3 p.m. Monday to:

Scaffolds Fruit Journal
Editors: A. Agnello, D. Kain
Dept. of Entomology, NYSAES
630 W. North St.
Geneva, NY 14456-1371
Phone: 315-787-2341   FAX: 315-787-2326
E-mail: ama4@cornell.edu