Archives for August 2017

August 10, 2017

Potato | Tomato Disease Forecast 8-11-17

Click to View | Download Report 8-11-17

Potato Disease Forecasting Report

We will be tracking DSVs for Late blight development and calculating P-days for initiating the first early blight fungicide application.

The first late blight fungicide application is recommended once 18 DSVs accumulate from green row. Green row typically occurs around the first week in May in southern NJ. An early season application of a protectant fungicide such as mancozeb (Dithane, Manzate, Penncozeb) or Bravo (chlorothalonil) as soon as the field is accessible is suggested. Please be vigilant and keep a lookout for suspect late blight infections on young plants. No late blight has been reported in our region to date.

Remember the threshold for P-days is 300!  Once 300 P-days is reached for your location, early blight fungicide applications should be initiated. Growers who are interested in using this model should choose the location above that is closest in proximity to their farming operation and should regularly check the Cornell NEWA website (http://newa.cornell.edu) where this information is compiled from. Click on Pests Forecasts from the menu, select your weather station, and click on tomato diseases, set accumulation start date, and a table of daily and total DSVs will be generated.

Tomato Disease Forecasting Report

Disease severity values (DSVs) for early blight, septoria leaf spot, and tomato anthracnose development are determined daily based on leaf wetness (due to rainfall, dew) and air temperature.

On a daily basis DSV values can range from 0 to 4 where 0 = no chance for disease development to 4 = high chance for disease development. DSVs are accumulated during the production season.

Fungicide applications are based on an individually determined DSV threshold. The first fungicide application for the control of these three diseases is not warranted until 35 DSVs have accumulated from your transplanting date. After that, growers can base fungicide applications on different DSV thresholds.

Reports generated by Ryan Tirrell

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 10, 2017

Vegetable Disease Update – 8/10/17

  • Late blight (US-23) was reported on tomato in Chester County in Southeastern PA this week. US-23 is active on both tomato and potato. All NJ tomato and potato growers are encouraged to scout their fields on a daily basis. Late blight has not been reported in NJ to date. If you suspect Late blight on your farm please contact your county Extension agent. To track the progress of Late blight in the US please visit USAblight.
  • Cucurbit downy mildew (CDM) on cucumber continues to be reported throughout the region. All cucumber growers should add downy mildew specific products to their regular maintenance programs. CDM has also been reported cantaloupe and Butternut squash in PA. CDM has also been reported in pumpkin as far north as North Carolina. To track CDM movement in the US please visit the North Carolina State University’s CDM Forecasting Website.
  • Bacterial canker and bacterial leaf spot in tomato are being reported. Bacterial leaf spot is also being reported in pepper.
  • Pepper anthracnose has been reported in the past week.
  • Dickeya dianthicola has been reported in 6 states and in 9 potato varieties to date including Dark Red Norland, Red Pontiac, Silverton, Yukon Gold, Kennebec, Norwis, Superior, Marcy, and Vivaldi.
  • Surveying for Dickeya dianthicola in potato fields and irrigation sources in NJ is currently on-going. If you suspect Dickeya, please contact your county agent. The best method for controlling Dickeya dianthicola in your operation is to adopt a zero-tolerance policy.
  • Want more information of what is going on around the mid-Atlantic region? Just click on the links to articles written by Extension personnel from PA, DE, VA, and WV on the right side of the page! You can also sign-up with and have information sent directly to you just like the NJ – Plant and Pest Advisory.
Filed Under: Commercial Ag Updates, Vegetable Crops
August 9, 2017

Vegetable IPM Update: Week Ending 8/9/2017

Note:  Due to technical difficulties, only sweet corn related maps and information will appear in this edition of the IPM Update.  We hope to resume full coverage next week.

Kris Holmstrom and Joe Ingerson-Mahar

Sweet Corn

European corn borer (ECB) adult numbers have again subsided, and no map will appear here.  As with last year, the second flight of ECB in New Jersey is low and sporadic.  While we are beginning to see limited feeding from this pest, it is relatively insignificant compared to fall armyworm (FAW) feeding that is now occurring on whorl stage sweet corn.  Insecticide applications should be made when 12% or more plants exhibit signs of ECB and/or FAW feeding.  FAW is, and will remain the dominant pest of vegetative stages of sweet corn for the remainder of the season.  Damage is extensive in the southern most counties, while it has increased only slightly over the past week in central and northern NJ.

Corn earworm (CEW) catches have gotten slightly more consistent in blacklight traps around the southern half of the state, while pheromone trap catches have risen dramatically in some areas (see CEW blacklight and pheromone trap maps).  Growers now treating silking sweet corn should adhere to silk spray schedules to limit damage.

The following are recommended silk spray schedules by region:

South – 3 days

Central – 4-5 days

North – 5-6 days

With frequent rains, the incidence of rust is increasing in some sweet corn plantings.  Additionally, northern corn leaf blight has also been discovered in the northern counties.  These diseases can be economically significant, particularly if they first appear in whorl stage plants.  Should this situation occur, growers need to consider fungicide applications to limit damage.  See the latest Commercial Vegetable Production Recommendations for suitable fungicides on this crop.

Filed Under: Vegetable Crops
August 7, 2017

Potato | Tomato Disease Forecast 8-8-17

Click to View | Download Report 8-8-17

Potato Disease Forecasting Report

We will be tracking DSVs for Late blight development and calculating P-days for initiating the first early blight fungicide application.

The first late blight fungicide application is recommended once 18 DSVs accumulate from green row. Green row typically occurs around the first week in May in southern NJ. An early season application of a protectant fungicide such as mancozeb (Dithane, Manzate, Penncozeb) or Bravo (chlorothalonil) as soon as the field is accessible is suggested. Please be vigilant and keep a lookout for suspect late blight infections on young plants. No late blight has been reported in our region to date.

Remember the threshold for P-days is 300!  Once 300 P-days is reached for your location, early blight fungicide applications should be initiated. Growers who are interested in using this model should choose the location above that is closest in proximity to their farming operation and should regularly check the Cornell NEWA website (http://newa.cornell.edu) where this information is compiled from. Click on Pests Forecasts from the menu, select your weather station, and click on tomato diseases, set accumulation start date, and a table of daily and total DSVs will be generated.

Tomato Disease Forecasting Report

Disease severity values (DSVs) for early blight, septoria leaf spot, and tomato anthracnose development are determined daily based on leaf wetness (due to rainfall, dew) and air temperature.

On a daily basis DSV values can range from 0 to 4 where 0 = no chance for disease development to 4 = high chance for disease development. DSVs are accumulated during the production season.

Fungicide applications are based on an individually determined DSV threshold. The first fungicide application for the control of these three diseases is not warranted until 35 DSVs have accumulated from your transplanting date. After that, growers can base fungicide applications on different DSV thresholds.

Reports generated by Ryan Tirrell

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 4, 2017

Potato | Tomato Disease Forecast 8-5-17

Click to View | Download Report 8-5-17

Potato Disease Forecasting Report

We will be tracking DSVs for Late blight development and calculating P-days for initiating the first early blight fungicide application.

The first late blight fungicide application is recommended once 18 DSVs accumulate from green row. Green row typically occurs around the first week in May in southern NJ. An early season application of a protectant fungicide such as mancozeb (Dithane, Manzate, Penncozeb) or Bravo (chlorothalonil) as soon as the field is accessible is suggested. Please be vigilant and keep a lookout for suspect late blight infections on young plants. No late blight has been reported in our region to date.

Remember the threshold for P-days is 300!  Once 300 P-days is reached for your location, early blight fungicide applications should be initiated. Growers who are interested in using this model should choose the location above that is closest in proximity to their farming operation and should regularly check the Cornell NEWA website (http://newa.cornell.edu) where this information is compiled from. Click on Pests Forecasts from the menu, select your weather station, and click on tomato diseases, set accumulation start date, and a table of daily and total DSVs will be generated.

Tomato Disease Forecasting Report

Disease severity values (DSVs) for early blight, septoria leaf spot, and tomato anthracnose development are determined daily based on leaf wetness (due to rainfall, dew) and air temperature.

On a daily basis DSV values can range from 0 to 4 where 0 = no chance for disease development to 4 = high chance for disease development. DSVs are accumulated during the production season.

Fungicide applications are based on an individually determined DSV threshold. The first fungicide application for the control of these three diseases is not warranted until 35 DSVs have accumulated from your transplanting date. After that, growers can base fungicide applications on different DSV thresholds.

Reports generated by Ryan Tirrell

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 2, 2017

Fruit IPM for August 2, 2017

Peach:

Oriental Fruit Moth (OFM): The third flight is on the way down in southern counties, and northern counties. Populations are low in peaches, but higher in apples.

[Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit