12 May 2026 - Timing Considerations for the Season, Scab & Fire Blight updates

Petal Fall Meeting Schedule

Western NY: Post-Bloom Insect & Disease Management, Freeze Events Info, and Thinning Recommendations Webinar

• Wednesday, May 13, 4-5:30 PM

• https://cornell.zoom.us/j/93057550896?pwd=u2RBsT8jNARGMcOuW69fKRwyBObKPq.1&from=addon

Capital Region: Saratoga/Mohawk Valley Petal Fall Webinar

• Thursday, May 14, 4-5:30 PM

• https://cornell.zoom.us/j/98474224521?pwd=cla7pvnKFc32wypoaR0AMyVCwsDTR8.1

Southern Hudson Valley: Ulster County In-Person Thinning Meeting

• Friday, May 15, 3-5pm

• Weed Orchards Farm Winery & Café 43 Mt. Zion Rd. Milton, New York

Northern Hudson Valley: Columbia County In-Person Thinning Meeting

• Tuesday, May 19, 2-4pm

• Cornell Cooperative Extension - Hudson Office CCE Regional Extension Center 479 NY-66 Hudson, New York

Historical Phenology and Average Degree Day Accumulation Base 43 (for reference)

• Pink (McIntosh) || 289 ± 26 || 3-May ± 7 days

• Full bloom (McIntosh) || 378 ± 35 || 10-May ± 6 days

• Petal fall (McIntosh) || 479 ± 42 || 18-May ± 6 days

Phenology & DDs for NY NEWA Stations from 1/1 – 5/11

Station || Stage || DD 43F || DD 43 Forecast Through 5/17

Geneva (AgriTech North) || Bloom || 510 || 587

Highland (HVRL) || Petal Fall || 619 || 719

Clifton Park || Bloom || 495 || 580

Peru (Forrence) || Pink, King Bloom || 345 || 421

Medina (Roberts) - Inland || Bloom || 470 || 541

Appleton North - Lake || Bloom || 356 || 422

Fairville (The Apple Shed) - Inland || Bloom || 498 || 569

Williamson (DeMarree) - Lake || Bloom || 424 || 470

*all DDs Baskerville-Emin, B.E

Upcoming Pest Events

Pest/Phenology Event || DD Base 43˚F || Approx. Date

STLM Traps set out || 1-Apr

Pear psylla – egg laying || 84 ± 44 || 33 ± 21 || 4-Apr ± 11 days

RBLR – 1st catch || 144 ± 32 || 60 ± 20 || 17-Apr ± 9 days

Rosy apple aphid – 1st nymphs present || 189 ± 55 || 86 ± 30 || 25-Apr ± 7 days

STLM – 1st adult catch || 168 ± 48 || 73 ± 28 || 20-Apr ± 9 days

STLM – 1st egg observed || 208 ± 65 || 94 ± 36 || 27-Apr ± 5 days

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Tight cluster (McIntosh) || 228 ± 27 || 105 ± 19 || 27-Apr ± 7 days

Tarnished plant bug – 1st observed || 222 ± 105 || 105 ± 62 || 25-Apr ± 15 days

OBLR – 1st overwintered larvae observed || 236 ± 78 || 112 ± 48 || 29-Apr ± 7 days

Black stem borer – 1st adult catch || 283 ± 50 || 137 ± 40 || 6-May ± 3 days

European red mite – egg hatch observed || 284 ± 53 || 134 ± 34 || 6-May ± 4 days

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Pink (McIntosh) || 289 ± 26 || 139 ± 21 || 3-May ± 7 days

OFM Traps set out || Pink

Oriental fruit moth – 1st adult catch || 229* ± 44* || 126 ± 33 || 2-May ± 8 days

RBLR – 1st flight peak || 303 ± 75 || 150 ± 48 || 4-May ± 9 days

STLM – 1st flight peak || 337 ± 71 || 168 ± 45 || 7-May ± 8 days

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Full bloom (McIntosh) || 378 ± 35 || 192 ± 25 || 10-May ± 6 days

OBLR Overwintered Gen. Sample || Bloom

Codling Moth Traps set out || Bloom

Petal fall (McIntosh) || 479 ± 42 || 252 ± 32 || 18-May ± 6 days

Lesser appleworm – 1st flight peak || 569 ± 205 || 313 ± 130 || 22-May ± 13 days

Plum curculio – 1st oviposition scars observed || 555 ± 77 || 286 ± 37 || 25-May ± 9 days

Pear psylla – hardshell stage observed || 569 ± 87 || 312 ± 51 || 22-May ± 9 days

Lesser peachtree borer – 1st adult catch || 570 ± 94 || 308 ± 59 || 24-May ± 8 days

San Jose scale – 1st flight peak || 644 ± 89 || 355 ± 58 || 29-May ± 8 days

Scouting and Monitoring Resources

Video: Apple Insect Targets and IPM Practices (including explanations of Degree Day calculations), https://youtu.be/NwyBAcvbpUs

NY Tree Fruit Pest Monitoring Network Blog

https://blogs.cornell.edu/treefruitpests/

Quick Guide for Apple Insect Pests https://help.nysipm.org/hc/en-us/articles/23290226665751-NEWA-Quick-Guide-for-Apple-Insect-Pests

Virtual Orchard Scout Training webinar recording on the Cornell IPM YouTube channel

https://www.youtube.com/watch?v=OtyOWCL1Q2A

Apple IPM Intensive Workshop playlist https://www.youtube.com/playlist?list=PLoNb8lODb49vifrm9Tla4GmAVhlIL0527

Northeast Regional Climate Change Monthly Maps

https://www.nrcc.cornell.edu/regional/monthly/monthly.html