peachtree borer — Plant & Pest Advisory

May 19, 2025 Tim Waller, William Errickson and Steven K. Rettke

Ornamental IPM 5/13 Recording Upload – NUMEROUS PEST ALERTS

Still time to Sign up for the 2025 – Rutgers Ornamental IPM Program

(Join us for the next Session Tuesday 5/27/25)

PREVIOUS SESSION: (contains information on boxwood pests, armored scales, needlecast diseases, oomycetes )

Note we have clearwing borer lures and wing or delta traps, scale crawler tape, and yellow sticky cards available to commercial grower program members at our Cumberland (twaller@njaes.rutgers.edu) and Monmouth (william.errickson@njaes.rutgers.edu) RCE offices.

ALERTS:

Scale crawler emergence throughout the state
Spruce spider mite activity and damage
Boxwood Blight Risk Model for next 7days
Bronze Birch Borer (BBB) approaching adult emergence
Clearwing Borer adult flight – time to monitor / treat
Red-headed flea beetle (RHFB) egg hatch – adult emergence
Oomycete material considerations

Previous webinars:

Click here for a PDF of April 22, 2025 webinar (contains information on RHFB and early Clearwing borer treatments) Click here for VIDEO of April 22, 2025 webinar
Click here for a PDF of April 08, 2025 webinar (Contains information on aphids and boxwood leafminer) Click here for VIDEO of April 08, 2025 webinar

(click the ‘Read More’ below for complete dates in S-C-Northern NJ per pest)

April 30, 2024 Tim Waller

Nursery Update 4/30/24 -Boxwood blight, borers, flea beetles

Please note: The Rutgers Nursery and Green Industry Working Group is working to deliver regular pest and disease updates throughout the season. These will be in addition to important alerts, critical topics, and pesticide credit opportunities. This tool is made for you, the commercial agriculture business, so please let us know if there are particular topics you would like to see included in the regular update.

Email: twaller@njaes.rutgers.edu Phone: 856-451-2800 Ext. 1.

Insect Pests

*Projected GDD50 accumulation as of 4/30/2024*
CODE	Location	1-Apr	1-May	1-Jun	1-Jul	1-Aug
NJ50	Upper Deerfield (South)	47	237	696	1408	2308
D4116	Bridgeton (South)	45	172	632	1346	2243
KMIV	Millville Airport (South)	57	249	676	1362	2237
NJ05	Greenwich (South)	53	247	716	1436	2338
NJ10	Howell (Central)	33	172	551	1191	2026
N59	High Point (North)	18	117	440	990	1711
USPEST.ORG – Model: *simple average/growing degree-day*, Min: 50F – Max: 95F, NMME forecast
Forecast: 7-month NMME based seasonal climate forecast (USPEST.ORG) – *Subject to change regularly = Check Often*

Please download and print the Rutgers Nursery and Landscape Pest Scouting Guide or Conifer and Christmas Tree Pest Scouting Guide and refer to this post “Obtaining your local growing degree-days (GDD)” for additional information. (See pest scouting guides for complete list of references)

Please SHARE what you SEE!! If you see a pest, disease, otherwise interesting or troublesome issue please report it to the Working Group by following the QR Code on the front of the Pest Scouting Guides or by filling out this reporting form.

Keep reading for more ALERTS – Boxwood Blight risk this week – Red-headed flea beetle timing, borer activity, and upcoming pests.

May 24, 2022 Tim Waller

Nursery Pests Scouting June – Bagworms, Scales, Borers, RHFB, BWB

Red-headed flea beetle – Adult emergence beginning any day now

Please refer to this timeline of pest development compiled by Tim Waller in communication with Brain Kunkel (Unv. Del) and Danny Lauderdale (NC State)

Contains material selection and timing, along with regime information and considerations

Boxwood Blight Alert – Infection Potential (Saturday) 5/27

Boxwood Blight Risk Assessment as of 5/24/2022
Region	Location	CODE	24-May	25-May	26-May	27-May	28-May	29-May
Southern	Upper Deerfield	NJ50	Very Low	Very Low	Low	High Risk	Very Low	Very Low
Central	Howell / Freehold	NJ10	Very Low	Very Low	Low	Infection Risk	Very Low	Very Low
Northern	High Point	NJ59	Very Low	Very Low	Very Low	Infection Risk	Very Low	Low
Check local boxwood blight risk here (CLICK HERE – input your area code – select closest weather station – check 7-14 prediction – click on graph / table)

Refer to the most recent Alert for more information – CLICK HERE

Pest Scouting – Please refer to these documents for a full listing of insects pests for your area corresponding to growing degree-days (GDDs).

Nursery and Landscape Pest Scouting Guide 2022 PDF (note this contains conifer pests as well)
Conifer Pest Scouting Guide 2022 PDF

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

The following key groups of pests will be active, vulnerable, or otherwise treatable during the next month throughout most of NJ. Here, bagworms, scale insects and borers with key life stage events during the 350-1500 GDD timeframe are discussed. Note there are many other insect pests present this time of year so please view the pest scouting guides above for your particular needs.

Projected GDD50 accumulation as of 5/24/2022 (USPEST)						Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region	Location	Station	24-May	1-Jun	1-Jul
South	Upper Deerfield	NJ50	488	638	1358
Central	Howell / Freehold	NJ10	426	551	1203
North	High Point	NJ59	288	387	909
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information

BAGWORMS (600-900 GDD) (Bagworm hatch prediction as of 5/24/22 – now until July 14 (Southern NJ (NJ50)))

Crop type

Common Name

Scientific Name

GDD Min (50F)

GDD Max (95F)

Reference

Developmental / Target Stage

Conifer mostly, many minor hosts

Bagworm

Thyridopteryx ephemeraeformis

600

900

Larvae (early instars) –

ONLY CONTROL WINDOW

Refer to this post for additional information on Bagworms

BORER Insect Activity for 350 – 1500 GDD (Now until ~July 1 in Southern NJ (NJ50))
Crop type	Common Name	Scientific Name	GDD Min (50F)	GDD Max (95F)	Reference	Developmental / Target Stage
Malus, Prunus, many	Lesser peach tree borer	Synanthedon pictipes	350	375	4	Adult flight, egg laying
Dogwood, apple, pecan, elm, hickory, willow	Dogwood borer	Synanthedon scitula	350	850	4	adults, eggs, caterpillars
Birch	Bronze Birch Borer	Agrilus anxius	440	880	RU	Adults (egg laying)
Malus, Prunus, many	Peach Tree Borer	Synanthedon sp.	500	600	RU	Adults – emerge (1st treatment both types)
Rhododendron	Rhododendron borer	Synanthedon rhododendri	509	696	RU	Adults emerge
Malus, Prunus, many	Greater peach tree borer	Synanthedon exitiosa	575	710	4	Adult emergence
Many	Roundheaded appletree borer	Saperda candida	802	1129	RU	Adults
Ash	Emerald ash borer	Agrilus planipennis	1000	1200	4	Peak adult activity
Malus, Prunus, many	Peachtree borer	Synanthedon sp.	1500	1800	RU	Larvae Treatment
Many	Roundheaded apple tree borer	Saperda candida	1514	1798	5	Typical treatment window
Conifer	Nantucket tip moth	Rhyacionia frustrana	1514	1917	RU	Adults 2nd generation

Click here – “Identifying Clearwing Moth Borers in Pheromone Traps” or “Differentiating the Common Wood Borers of Ash Trees”

May 13, 2022 Tim Waller

Pest Scouting 200-500 GDD – Get sprayers ready for Borers, Scale Crawlers, and other important pests

It’s that time of year again, many scale crawlers and borers will be active over the next few weeks throughout NJ. Be prepared to target specific pest life-stages for the highest level of efficacy per material cost and get those problem insects in check. Application of contact insecticides during specific activity windows for these pests should be coupled with systemic applications now to help protect woody plants later on.

Borers attack stressed plants. If you recently dug then heeled-in trees, transplanted seedlings, or otherwise seriously stressed a tree, please consider taking immediate action to protect them from both adult flights (contact trunk sprays) and future infestations (systemics)

Please Download these resources: (The scouting guide is for you to print and keep on hand…these are just updates)

Nursery and Landscape Pest Scouting Guide 2022 PDF (note this contains conifer pests as well)

Conifer Pest Scouting Guide 2022 PDF

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

Projected GDD50 accumulation as of 5/13/2022						Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region	Location	Station	13-May	1-Jun	1-Jul
South	Upper Deerfield	NJ50	297	603	1323
Central	Howell / Freehold	NJ10	242	508	1160
North	High Point	NJ59	135	345	867
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information

April 7, 2014 Richard Buckley

Goes to Show You Don’t Ever Know

Last week, we saw photographs of cherrylaurel that got pummeled by the winter. Of course, I proved my plant ignorance in the blog post by calling the photos of cherrylaurel, Prunus laurocerasus, mountain laurel, which is Kalmia latifolia. No doubt mountain laurel got hurt in the winter just the same as cherrylaurel did and no doubt I need a better editor!

Winter injured cherrylaurel. Photo: Richard Buckley, Rutgers PDL