Archives for August 2018

August 30, 2018

Potato | Tomato Disease Forecast 8-31-18

Click to View | Download Report 8-31-18

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.

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 30, 2018

Fall control of perennial weeds with herbicides

Late summer and fall are perfect times to work on tough-to-control perennial weeds such as Virginia creeper vine, bindweed, green-brier, Canada thistle, goldenrod, and poison ivy. These perennials are among the most difficult weeds to eradicate, especially because of their ability to generate new shoots from their root systems. Successful management strategies will mostly rely on herbicide that can move from the leaf to the below-ground plant parts. Timely initial application and consistency at controlling any regrowth with follow-up spot treatments are crucial for long-term control of these weeds.

3 different species of weeds that affect blueberries

Field bindweed (upper left), goldenrod (lower left) and green-brier (right) are some tough weed species of NJ blueberry and will warrant extra time for achieving successful control

Glyphosate (Roundup or other generic products) is the only postemergence herbicide labeled on blueberry that can provide good control of perennial weeds. Late summer and fall are good times for applying glyphosate as plant sap movement is mostly directed toward the roots where nutrients will be stored in anticipation of next season. Therefore, large volume of glyphosate can easily be translocated from the leaves to the roots, improving the efficiency of the herbicide at killing below-ground storage organs. It is VERY IMPORTANT for glyphosate to be applied when weed leaves are still green before fall colors appear.

Use extreme care not to contact crop green tissues (stems and leaves) with glyphosate. Glyphosate absorbed by crop green leaves and bark moves within the plant and can severely damage or kill above-ground and below-ground parts of annual crop and perennial treess. Weeds such as bindweed, Virginia creeper, and greenbrier may need to be pulled out of the trees so they can be treated safely. This may seem too slow to be practical, but consider what these weeds cost in lost income. For example, blueberry bushes covered by Virginia creeper vine may yield just 20% of their potential. This easily equates to a $5 to $10 loss per bush. The loss is incurred each year and increases as the vines spread to neighboring bushes. Investing 15 minutes to carefully pull vines out of that bush and safely treat them on the ground is money well spent.

Glyphosate should be applied through low pressure spot treatment to limit drift movements. Glyphosate absorption will be improved if ammonium sulfate (17 lbs / 100 gal water) is added to your spray mixture. For effective control, at least 50% of the foliage should be wet with glyphosate applied as a 2% solution (see your product’s label for rate necessary to reach this concentration).

Consider also “cut stump” applications for Virginia creeper or poison ivy that have large diameter stems. Apply a 2% glyphosate solution to the cambium (inner bark area) IMMEDIATELY after cutting the stem. Don’t let time for cutting to dry as this would prevent glyphosate absorption and translocation to below-ground plant parts.

Always apply glyphosate on weeds that are actively growing and not under drought stress.

Always refer to the commercial product label for rates and additional information.

Filed Under: Blueberry, Cranberry, Fruit, Tree Fruit, Vegetable Crops, Wine Grape
August 29, 2018

IPM Update 08/29/18

Sweet Corn

European corn borer (ECB) moth catches are extremely low.  The second flight has been very weak.  Feeding signs in whorl corn remain low.  There will be no map in this edition.  Second generation feeding is often obscured by fall armyworm (FAW) feeding.  Once plants hit full tassel, any ECB larvae present will move downward on the stalk and re-enter the plant near the area where ears are forming.  This can result in direct injury to the ear.  Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward.  This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]

Filed Under: Organic Production, Vegetable Crops
August 27, 2018

Potato | Tomato Disease Forecast 8-28-18

Click to View | Download Report 8-28-18

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.

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 23, 2018

Potato | Tomato Disease Forecast 8-24-18

Click to View | Download Report 8-24-18

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.

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting Tagged With: ,
August 23, 2018

Insane Rain

The summer of 2018 isn’t going away quietly for many in New Jersey. August 2018 will be remembered for a steady dose of torrential rain that has made turfgrass management extremely difficult, especially in the northern half of the state. In the last 30 days, over 12 inches of rain have fallen across several counties […]

Map of 30 days of precipitation in NJ
  
Filed Under: Landscape, Nursery, & Turf, Turf