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…]

HIGH potential for Boxwood Blight this Thursday 4/6

There is a potential for boxwood blight infections this WEDNESDAY and THURSDAY throughout much of NJ – especially central regions. Thursday’s high temperatures coupled with prolonged periods of leaf wetness overnight will contribute to the spread of boxwood blight infections.

If BWB is important to your business Use the USPEST – PUSH Alerts – (click here) – to setup weekly email alerts. Create an account, watch the tutorial, and then set up your subscriptions. You select which locations (as many as you like), days you want to receive emails (pick Sunday/Monday), and what you would like to receive alerts about (BWB and a variety of other pests and diseases). Rutgers is not directly affiliated, however this is an incredible tool. 

  • It is time to begin protective fungicide applications in high value areas if you have not already done so! 

  • Protective fungicide applications should remain in effect or be initiated immediately for Boxwood Blight in “Infection risk or High Risk areas”. 
  • If your area is not listed (throughout all of NJ please visit the USPEST.ORG Boxwood Blight Risk Model – CLICK HERE TO CHECK YOUR LOCAL PREDICTIONS

Boxwood Blight risk-model information, considerations, and links:

Boxwood Blight Risk Assessment as of 4/4/2022
Region Location CODE 3-Apr 4-Apr 5-Apr 6-Apr 7-Apr 8-Apr
Southern Upper Deerfield NJ50 Very Low  Low  Minor Risk Very Low  Very Low  Very Low 
Central Howell / Freehold NJ10 Very Low  Low  Minor Risk Very High Very Low  Very Low 
Northern High Point NJ59 Very Low  Very Low  Low  High Risk Very Low  Very Low 
Monday Tuesday Wednesday Thursday Friday Saturday
 Please check YOUR LOCAL risk (click here)

[Read more…]

Immediate potential for Boxwood Blight 3/24 and 3/25 – First infection potentials

There is a potential for new boxwood blight infections this FRIDAY and SATURDAY throughout much of NJ – especially central regions. Increased temperatures and prolonged periods of leaf wetness will contribute to the spread of boxwood blight infections.

  • It is time to begin protective fungicide applications in high value areas if you have not already done so! 

  • Protective fungicide applications should remain in effect or be initiated immediately for Boxwood Blight in “Infection risk or High Risk areas”. 
  • If your area is not listed (throughout all of NJ please visit the USPEST.ORG Boxwood Blight Risk Model – CLICK HERE TO CHECK YOUR LOCAL PREDICTIONS

Boxwood Blight risk-model information, considerations, and links:

Boxwood Blight Risk Assessment as of 3/22/2023
Region Location CODE 22-Mar 23-Mar 24-Mar 25-Mar 26-Mar 27-Mar NOTES
Southern Upper Deerfield NJ50 Very Low  Low Low  Infection Risk Very Low  Very Low 
Central Howell / Freehold NJ10 Very Low  Low HIGH Risk HIGH Risk Very Low  Very Low  High prob. of first BWB infections
Northern High Point NJ59 Very Low  Very Low   Infection Risk Very Low Very Low  Very Low 
 Please check YOUR LOCAL risk (click here)

(input your area code – select closest weather station – check 7-14 prediction – click on graph / table)

These advisories are general in nature, change rapidly over time, are site-specific…therefore  Someone from your business should be using this risk model daily if boxwood is important to your financial stability– In 30 seconds you can have a better idea of boxwood blight (and other pathogen) activity in your immediate area! Please contact Tim Waller if you need help using this service (twaller@njaes.rutgers.edu), we want to help! 

Fungicides; 

  1. You very well may have these materials already applied as ‘cover-sprays’ – But – be mindful that protectant fungicides loose efficacy the more rain (or overhead irrigation) they are subjected to, and reapplication may be warranted.
  2. ROTATE between Fungicide Resistance Action Committee (FRAC codes) to avoid this pathogen becoming resistant to specific chemicals

Format: [FRAC code]: Chemical name (Trade names * no endorsement implied, other options exist)  

  • [M05]: Chlorothalonil (Daconil WS)
  • [M05 + 1] Chlorothalonil + Thiophanate methyl (Spectro 90WDG)
  • [11] Trifloxystrobin + [7] Fluopyram  (Broadform)
  • [11] Trifloxystrobin + [3] Triadimefon (Armada 50WDG)
  • [M03] Mancozeb
  • [12] Fludioxonil (Medallion WDG)
  • [3] Tebuconazole (Torque)BW

DISCLAIMER: The label is the law, always refer to it for allowable host crops, use-restrictions, application rates, reapplication intervals, re-entry intervals (REI), and mix compatibility information. Production and pesticide information on this site are for private/commercial pesticide applicators and landscape professionals only, and are NOT for home gardener use. Provided materials represent examples and do not cover all possible control scenarios. Trade-names listed do not imply endorsement and are used as examples only. Please contact your local agent or chemical sales representative for more information or to discuss additional pest management options.

Resources 

Background on the pathogen: 

Understanding Protectant Fungicides
(FRAC groups M01 – M12) in 2022

Protectant (contact) fungicides, such as the inorganics (copper, FRAC group M01) and sulfur (FRAC code M02); the dithiocarbamates (mancozeb, M03), phthalimides (Captan, M04), and chloronitriles (chlorothalonil, M05) are fungicides which have a low chance for fungicide resistance to develop. Protectant fungicides typically offer broad spectrum control for many different pathogens.

Why wouldn’t fungi develop resistance to protectant fungicides? Protectant fungicides are used all the time, often in a weekly manner throughout much of the growing season.

[Read more…]

Infection potential for Boxwood Blight in the next 48h – PROTECTANT fungicide applications should remain in effect

There is a potential for new boxwood blight infections today and tomorrow with the rain/humidity and higher temperatures

– Protective fungicide applications should remain in effect or be initiated immediately for Boxwood Blight (nursery and landscape settings) –

 

Boxwood Blight risk-model information, considerations, and links:

Boxwood Blight Risk Assessment as of 5/4/2021
Region Location CODE 3-May 4-May 5-May 6-May 7-May 8-May
Southern Upper Deerfield NJ50 Very Low  Infection Risk Infection Risk Very Low  Very Low  Very Low 
Central Howell / Freehold NJ10 Very Low  Low  Low  Very Low  Very Low  Very Low 
Northern High Point NJ59 Very Low  Very Low Low  Very Low  Very Low  Very Low 
Please check your local boxwood blight risk here (click here and type in your area code – select closest station)

 

  • These advisories are general in nature and change rapidly so someone from your business should be using this risk model (CLICK HERE) daily if boxwood is important to your financial stability – In 30 seconds you can have a better idea of boxwood blight (and other pathogen) activity in your immediate area!
    • (click on the link – input area code – select closest weather station – check 7-14 prediction – click on graph / table) 

Fungicides; 

  1. You very well may have these materials already applied as ‘cover-sprays’ – But – be mindful that protectant fungicides loose efficacy the more rain they are subjected to, and reapplication may be warranted.
  2. ROTATE between Fungicide Resistance Action Committee (FRAC codes) whenever possible

Format: [FRAC code]: Chemical name (Trade names)

  • [M05]: Chlorothalonil (Daconil WS)
  • [M05 + 1] Chlorothalonil + Thiophanate methyl (Spectro 90WDG)
  • [11] Trifloxystrobin + [7] Fluopyram  (Broadform)
  • [11] Trifloxystrobin + [3] Triadimefon (Armada 50WDG)
  • [M03] Mancozeb
  • [12] Fludioxonil (Medallion WDG)
  • [3] Tebuconazole (Torque)

 

DISCLAIMER: The label is the law, always refer to it for allowable host crops, use-restrictions, application rates, reapplication intervals, re-entry intervals (REI), and mix compatibility information. Production and pesticide information on this site are for private/commercial pesticide applicators and landscape professionals only, and are NOT for home gardener use. Provided materials represent examples and do not cover all possible control scenarios. Trade-names listed do not imply endorsement and are used as examples only. Please contact your local agent or chemical sales representative for more information or to discuss additional pest management options.

Resources 

Understanding Protectant Fungicides
(FRAC groups M01 – M11)

Protectant (contact) fungicides, such as the inorganics (copper, FRAC group M01) and sulfur (FRAC code M02); the dithiocarbamates (mancozeb, M03), phthalimides (Captan, M04), and chloronitriles (chlorothalonil, M05) are fungicides which have a low chance for fungicide resistance to develop. Protectant fungicides typically offer broad spectrum control for many different pathogens.

Why wouldn’t fungi develop resistance to protectant fungicides? Protectant fungicides are used all the time, often in a weekly manner throughout much of the growing season.

[Read more…]