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Healthy Fruit 2010 Vol. 18:10

Jun 8, 2010

Current (through June 4) degree day (DD) Accumulations

Location: UMass Cold Spring Orchard (CSO), Belchertown, MA

Base 43: 1034

Base 50: 629

Significant upcoming orchard pest events based on degree days (Base 43):

Lesser appleworm 1st flight subsides: 990-1446

Pear psylla 2nd brood nymphs hatch: 967-1185

Obliquebanded leafroller 1st flight peak: 843-1139

Obliquebanded leafroller summer larvae hatch: 1038-1460

Peachtree borer 1st catch: 779-1347

Oriental fruit moth 1st flight subsides: 834-1120

Cherry fruit fly first catch: 755-1289

Spotted tentiform leafminer 2nd flight begins: 982-1152

Orchard Radar insect synopsis (for Belchertown)

First dogwood borer (DB) egg hatch roughly: June 15. Peak hatch roughly: July 23

Codling moth (CM) development as of June 8: 1st generation adult emergence at 90% and 1st generation egg hatch at 49%. In most orchards, insecticide targeted against plum curculio and apple maggot prevent codling moth damage. If targeted codling moth control is needed, key management dates are: 1st generation 20% CM egg hatch: June 2, Wednesday (= target date where one spray needed to control 1st generation codling moth)

1st generation Obliquebanded Leafroller (OBLR) flight begins around: May 28, Friday. Where waiting to sample late instar OBLR larvae is not an option (= where OBLR is known to be a problem, and will be managed with insecticide against young larvae): Early egg hatch and optimum date for initial application of B.t., Delegate, SpinTor, Proclaim, Intrepid, Rimon, Altacor, Belt, pyrethroid or other insecticide effective against OBLR (with follow-up applications as needed): June 13, Sunday. Where waiting to sample late instar OBLR larvae to determine need for treatment is an option, or to check on results from earlier sprays: Optimum sample date for late instar summer generation OBLR larvae: June 23, Wednesday If first OBLR late instar larvae sample is below threshold, date for confirmation follow-up: June 27, Sunday

2nd generation adult Spotted Tentiform Leafminer (STLM) begins around June 3, Thursday

Upcoming meetings

June 15, 16, 17: Tree fruit twilight meetings

Tuesday, June 15, Clark Brothers Orchards, 580 Apple Valley Rd., Ashfield,M, 5:30 PM

Wednesday, June 16, Parlee Farms, 95 Farwell Rd., Tyngsboro, MA, 5:30 PM

Thursday, June 17, Pippin Orchard, 751 Pippin Orchard Rd., Cranston, RI, 5:30 PM

Tree fruit twilight meetings start promptly at 5:30 PM.

1 (one) pesticide recertification credit will be offered.

There will be a $25 meeting admission charged at the door. ($20 for Massachusetts and Rhode Island Fruit Growers' Association FULL members.)

A light meal or snack will be served at all meetings.

For more information, call Jon Clements: 413-478-7219 or Heather Faubert: 401-874-2967

July 15, 2010: Massachusetts Fruit Growers' Association Summer Meeting, UMass Cold Spring Orchard, Belchertown, MA (details forthcoming)


The way I see it

I am seeing more and more plum curculio injury on 'marginally' sprayed trees. Honeycrisp seems to be preferred to McIntosh. Seems we may have had an active curculio season.

Hand thinning of peaches should start ASAP if not already -- remember, we are probably still 2 weeks ahead of schedule so the peaches think it is mid-late June already. Ditto for apples, however, there may still be some June drop. But do apples ASAP to get the benefit of return bloom in addition to fruit size and crop load management.

Cherry harvest will be on the very early (10 days) side -- Chelan, Cavalier, and Black Pearl sweet cherries will be ready later this week; Jubileum tart cherry also. The cedar waxwings have arrived in force.

Peaches (and apples) could get another shot of nitrogen fertilizer now if warranted. I look at leaf color and shoot growth as good indicators of the need for more nitrogen right now.

I've caught dogwood borer in pheromone traps (see pict at end of HF) but no peachtree borers (yet). Trunk spray of chlorpyriphos (Lorsban or generic) should be applied to all dwarf apple trees, and either trunk spray or pheromone mating disruption for peachtree borers. Trunk spray can be done anytime you have a chance starting now and into July.

Calcium should be added to all apple cover sprays, and starting pretty soon, consider adding NAA (Fruitone L) at 2 oz. per acre to enhance return bloom. See Fact Sheets: F-119R Foliar Calcium Sprays for Apples and F-131 Enhancing Return Bloom on Apple with Plant Growth Regulators

Not quite enough leaf wetness hours have accumulated since petal fall to trigger the first fungicide spray for sooty blotch and flyspeck (SBFS) according to the SBFS model. I expect, however, by next week we will have. Consider starting your summer fungicide sprays (remembering everything is early this year) next week, i.e. the 3rd week in June. For very good articles on modeling summer disease sprays, and fungicide efficacy/depletion, see: Summer Diseases in a previous Healthy Fruit and Flyspeck fungicide spray re-estimates on Orchard Radar.

Young apple trees should be actively trained and pruned (as necessary). Making sure the leader stays dominant by 'stripping' competing shoots, use clothespins to establish wide branch angles, and tying down feathers on 1st leaf tall-spindle orchards should be ongoing activities now.

That's all for now.


WANTED: Dogwood borers, Peachtree borers, Round- or Flat-headed Apple borers, or other boring insects.

We are doing biocontrol of Emerald Ash Borer (EAB), a beetle from China that has already killed 10's of millions of ash trees in the Midwest and has spread to 13 states, including NY. We have already tested and released three parasitic wasps from China for biocontrol, but we will be getting a new parasitic wasp from Russia in a few weeks. We need to conduct safety tests to ensure that if we release this species it will only attack the EAB and not other native borers. To do that, we need to find and rear native borers. Would you please help us and give us a call if your orchard is infested with boring insects (we can collect either adults or mature larvae). We would be happy to take them off your hands and put them to good use. Please contact Tracy Ayer (ext. 248) or Juli Gould (ext. 220) at 508-563-9303 or send us an email at or Thank you in advance.

Juli Gould, Entomologist


Buzzards Bay, MA


Apple Scab Fungicide Resistance Survey 2010

This, from Kerik Cox at Cornell. To the best of my knowledge, it is open to non-NY growers too. JC

Scab is show up all over NY and surrounding states and we're already testing orchards. If you want to participate in the 2010 apple scab fungicide resistant survey, please prepare to make a sample submission.

Fresh young scab lesions on cluster leaves are suitable, but fresh terminal leaf scab (coming later) is even better. If you want to send cluster leaf scab in the near future and terminal leaf scab later, that's fine with us. There are a lot of potential sources of attrition with this test, and it doesn't hurt to have an extra set of leaves to fall back on in case the first ones fail. We have only a limited number of slots open for testing in 2010, so be the first to get your scab samples in.

When you are ready to submit, go to our website ( and download the instructions and sample submission form. If you don't have the Internet access, contact a local Cornell cooperative extension support specialist, and have them provide you with a copy of the instructions and submission form.

Useful links

UMass Extension Fruit Program

UMass Cold Spring Orchard

Scaffolds Fruit Journal

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