Rutgers University | New Jersey Agricultural Experiment Station | Pesticide User Responsibility

Archives for July 2013

July 15, 2013

Tomato Disease Forecasting Report 7-16-13

7-16-13 Tomato Report – Click to Download

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.

Filed Under: Disease Forecasting
July 15, 2013

Potato Disease Forecasting Report 7-16-13

Potato Disease Forecasting Report 7-16-13 – Click to Download

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 New Jersey. An early season application of a protectant fungicide such as mancozeb (Dithane, Manzate, Penncozeb) or Bravo (chlorothalonil) as soon the field is accessible is suggested. Please be vigilant and keep a look out 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 chose 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.

Filed Under: Disease Forecasting
July 15, 2013

Cranberry: Root-feeding Pests

Occurrence of root-feeding insects will manifest by the presence of dead patches. Pull dead vines and search through the root zone and soil for grubs and worms.

If your beds have damage caused by root-feeding insects, you should consider treatment with Imidacloprid (e.g. Admire Pro, Alias 4F, Alias 2F) immediately after bees are removed. Admire Pro (imidacloprid) is labeled for the control of cranberry rootworm, white grubs (Phyllophagaspp.), and other scarabs in cranberries.

Damaged, Dead Patches in Cranberry

Damaged, Dead Patches in Cranberry

Phyllophaga Grubs

Phyllophaga Grubs


[Read more…]

Filed Under: Cranberry
July 12, 2013

How Rainfall Influences Residual Herbicides

Heavy rains the past month have caused concern that residual preplant incorporated and preemergence herbicide applications may and not provide the length of weed control expected and increase the risk of crop injury compared to when rainfall is closer to average.  The affect of the additional rainfall on herbicide activity and crop safety is complex, and is influenced the soil and the chemical properties of each herbicide. [Read more…]

Filed Under: Vegetable Crops
July 12, 2013

Kudza Bug Getting Closer to NJ

Adult Kudza Bug - Soybean Pest

Adult Kudza Bug – Soybean Pest

You may have read in different farming publications about the presence of bean platasipid (Megacopta cribraria), or more commonly the kudzu bug, in the southeastern US.
It is referred to as the kudzu bug because it has a tendency to feed on kudzu. This is not necessarily a bad thing in the south where kudzu is an exotic invasive species.

In the southeastern US kudzu bug has become a concern because it is also a pest of soybeans. This stink bug species is smaller than brown marmorated stink bug and has a different shape. Like brown marmorated stink bug it also can overwinter in homes.

This stink bug species was discovered in Georgia in 2009 and has since spread through out the southeast and is heading north. The kudzu bug has most recently been found in Sussex County Delaware. It has also been found in Maryland in Prince George, Charles, Calvert, and Anne Arundel counties. As kudzu bug is a soybean pest we need to keep a watchful eye for it here in New Jersey.

Filed Under: Commercial Ag Updates
July 11, 2013

Tomato Disease Forecasting Report 7-12-13

7-12-13 Tomato Report – Click to Download

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.

Filed Under: Disease Forecasting