Ornamental IPM – Blight and pest alerts – next IPM Session 5/13/25

  1. Serious potential for Boxwood Blight
  2. Bronze Birch Borer (BBB) approaching adult emergence
  3. Clearwing Borer adult flight – time to monitor
  4. Red-headed flea beetle (RHFB) egg hatch – adult emergence soon
  5. Oomycete material considerations
  6. (click the ‘Read More’ below for complete dates in S-C-Northern NJ per pest)

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

(Join us for the next Session Tuesday 5/13/25)

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.

[Read more…]

Nursery Pest and Disease Update 6/15/2023

In this edition:

  • Insects:
    • MORE Scale crawlers emerging
    • Borers
    • Beetles
  • Diseases:
    • Oomycete root diseases (Phytophthora, Pythium, Phytopythium)
    • Leaf spots / foliage diseases
    • Boxwood Blight – reminder
    • Virus observations
  • Nutrient Management 
    • Managing Soluble Salts by monitoring EC
    • Plant Tissue analysis
  • Plant Spotlight:
    • American Holly (Ilex opaca)
  • Cumberland Nursery / NJNLA – Twilight: tonight (6/15) for NURSERYMEN ONLY (contact twaller@njaes.rutgers.edu or 856-451-2800 Ext. 1. for details)

Please click “read more” below to get updates on pests, diseases, and other important resources for the week of 6/15/2023.

[Read more…]

Nursery Pest and Disease Update 5/15/2023

In this edition:

  • Insects:
    • Scale crawler emergence
    • Borer insects
    • Upcoming problem pests / Redheaded flea beetle / SLF / Pest Scouting Guides
  • Diseases:
    • Leaf spot / foliage disease management
    • Fire blight on Rosaceous hosts
    • Canker fungi
    • Boxwood blight
    • Oomycete root diseases (Phytophthora, Pythium, Phytopythium)
  • Plant Spotlight:
    • NJ native azalea species

Please click “read more” below to get updates on pests, diseases, and other important resources for the week of 5/15/2023.

[Read more…]

Nursery Pest Update 4/25 – 5/5/2023

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 4/25/2023 (these change throughout the season!)
Region Location 25-Apr 1-May 1-Jun 1-Jul 1-Aug
Southern Upper Deerfield (NJ50) 251 281 682 1370 2218
Central Howell / Freehold (NJ10) 188 207 537 1160 1957
Northern High Point (NJ59) 142 143 371 864 1507
Forecast: 7-month NMME based seasonal climate forecast (USPEST.ORG)

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.

Please continue reading for much more detailed and important information!

[Read more…]

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). 

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 RU 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”

[Read more…]

Nursery – Pest Scouting Guide for August – Reminders – Need a few more nurseries for Phytophthora sampling

NURSERY PEST SCOUTING GUIDE – August (1300-2200 GDD50)

Please download and print the pest scouting guide resource (printable version of the information below for your desk or truck) –(click on the link and then print)

Projected GDD50 accumulation as of 8/4/2021
Region Location 1-Aug 1-Sep 1-Oct 1-Nov
Southern Upper Deerfield (NJ50) 2145 2931 3477 3682
Central Howell / Freehold (NJ10) 1896 2630 3109 3249
Northern High Point (NJ59) 1490 2045 2352 2384
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

 

(Same material as downloads)

Pest Scouting – Growing Degree-day Ranges  (1600-3000 GDD50) 
CROP TYPE Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Redheaded flea beetle Systena frontalis 1570 1860 Udel. 2nd generation egg hatch
Many Two-banded Japanese weevil Pseudocneorhinus bifasciatus 1644 2271 RU Adults
Willow Willow twig aphids Lachnus spp. 1644 2271 5 Typical treatment window
Conifer Juniper webworm Dichomeris marginella 1645 1917 RU Larvae Treatment
Euonymus Euonymus Scale Unaspis euonymil 1700 RU Prophylactic 2nd generation treatments
Conifer Cryptomeria scale Aspidiotus cryptomeriae 1750 2130 RU, 4 Crawlers emerge (2nd generation)
Many Obscure scale Melanaspis obscura 1774 6 Egg hatch / crawler
Oaks Oak skeletonizer Bucculatrix ainsliella 1798 2155 RU Larvae
Conifer Arborvitae leafminer Argyresthia thuiella 1800 2200 RU Larvae Treatment (3rd generation)
Mimosa, Honeylocust Mimosa webworm Homadaula anisocentra 1800 2100 RU Larvae (2nd generation)
Conifer Cooley spruce gall adelgid Adelges cooleyi 1850 1950 RU Galls open (Spruce)
Many Redheaded flea beetle Systena frontalis 1878 2318 Udel. 2nd generation Adults feeding
Turf Hairy chinch bug  Blissus leucopterus 1903 2160 RU Second generation- 50%- 2nd instars
Tulip Tuliptree aphid Illinoia liriodendri 1917 2033 RU Nymphs
Conifer Zimmerman pine moth Dioryctria zimmermani 1917 2154 5 Treatment window (adult flight-1700 GDD)
Mainly Oaks Orangestriped oakworm Anisota senatoria 1917 6 Egg hatch – early instars
Conifer White pine aphid Cinara strobi 1991 2271 RU Adults
Rhododendron Azalea whitefly Pealius azaleae 2032 2150 5 Adults/nymphs (3rd generation)
Maple Sugar maple borer Glycobius speciosus 2032 2375 5 Typical treatment window
Conifer Maskell scale lepidosaphes pallia 2035 6 Egg hatch / crawler (2nd generation)
Mainly Tulip Tulip tree scale Toumeyella liriodendri 2037 2629 RU Crawlers (1st generation)
Mainly Magnolia Magnolia scale Neolecanium cornuparvum 2155 2800 RU Crawlers (1st generation)
Euonymus Euonymus Scale Unaspis euonymil 2235 6 Egg hatch / crawler (2nd generation)
Locust Locust borer Magacyllene robiniae 2271 2805 5 Typical treatment window
Poplar and Willow Poplar and willow borer  Crytorhynchus lapathi 2271 2806 5 Typical treatment window
Conifer Spruce spider mite  Oligonychus ununguis 2375 2806 5 Typical treatment window – fall activity
Many Southern red mite Oligonychus ilicis 2500 2700 5 Typical treatment window
Maple Japanese maple scale Lopholeucaspis japonica 2508 6 Egg hatch / crawler (2nd generation)
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 2515 2800 RU Fall control of overwintering stage
Conifer Elongate hemlock scale  Fiorinia externa 2515 2625 RU Typical treatment window – fall activity
Hardwoods Fall webworm Hyphantria cunea 2793 6 Egg hatch / crawler (2nd generation)
Conifer Cooley spruce gall adelgid Adelges cooleyi 2800 3000 3 Fall control of overwintering stage
Conifer Eastern spruce gall adelgid Adelges abietis 2800 3000 3 Fall control of overwintering stage
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. References RU Rutgers Cooperative Extension – Landscape IPM Notes
2 http://ccetompkins.org/resources/using-growing-degree-days-for-insect-management
3 https://extension.psu.edu/ipm-basics-for-christmas-trees#section-2
4 https://www.canr.msu.edu/ipm/agriculture/christmas_trees/gdd_of_conifer_insects
5 https://www.agriculture.nh.gov/publications-forms/documents/landscape-pests.pdf
Daily GDD50 =                                                                                                  (Max + Min temp.) / 2 – 50 (min temp. threshold) 6 https://extension.umd.edu/ipm/pest-predictive-calendar-landscapenursery
7 https://www.canr.msu.edu/ipm/agriculture/christmas_trees/gdd_of_landscape_insects
Unv. Del. Coorespondance with Dr. Kunkel (University of Delaware)-evolving GDD ranges
Compiled 8-04-2021 – Timothy J. Waller, Ph.D. – Rutgers Cooperative Extension, Cumberland County Nursery Crops – twaller@njaes.rutgers.edu

 


Redheaded flea beetle considerations:

Adults should be surfacing any day in the southern regions of the state. However, in two sentinel plot locations I have yet to see second generation adults as of 8/3/2021.

Contact materials aimed at managing developing larvae (especially growth regulators) may be particularly useful at this time. Contact materials or fast acting systemics should be used to target adults in the next few days to weeks. The use of long lasting systemics should also be considered to protect foliage from the next generations adults (if a third generation occurs) and again late season to guard from first generation adults in the 2022 spring season.

These GDD estimates and corresponding calendars are evolving as we continue to learn more about this pest. If you have high populations please contact Tim Waller so we can continue to adapt our recommendations in NJ.  Email: twaller@njaes.rutgers.edu

Please refer to this updated RHFB timeline printout for your desk or truck (as of 842021) (CLICK HERE)

 


SURVEY REQUESTS

WE NEED A FEW MORE FARMS!! Please answer a few questions if you would like to be included in a statewide Phytophthora in Conifer Nurseries sampling project 

Please fill out this brief survey if you are experiencing damages due to Redheaded flea beetle (RHFB)

Contact – Timothy J. Waller – twaller@njaes.rutgers.edu for more information