Vegetables

Vegetable Insects - Joanne Whalen, Extension  IPM Specialist;   jwhalen@udel.edu

 

Cucumbers.

We continue to find low levels of aphids in seedling stage cucumbers. A treatment should be applied for aphids if 10 to 20 percent of the plants are infested with aphids. Actara, Fulfill, Thiodan or Lannate will provide aphid control. A penetrating surfactant (e.g. LI-700 or AD-100) should be used with Fulfill.

 

Lima Beans.

Heavy leafhopper populations can also be found  on seedling stage lima beans. If nymphs are easily detected and you can find plant damage a treatment may be needed. As soon as pin pods are present, scout fields for lygus bugs and stinkbugs. Treatment should be considered if you find 15 adults and/or nymphs per 50 sweeps. Lannate, Capture or Warrior can be used if both species are present. A higher rate of Capture (4 oz/A), Mustang (4.3 oz/A) or Warrior (3.84 oz) will be needed if stinkbugs are the predominant insect present. Although our overwintering corn earworm population has been low to moderate, reports from Virginia indicate that pheromone trap catches are higher than normal. So, this could mean that we will see a heavy migratory population. As soon as pin pods are present, you should also begin sampling fields for corn earworm.

 

Melons.

Continue to scout all melons for aphids, cucumber beetles, and spider mites. Spider mite population levels continue to increase and multiple sprays may be needed.  A treatment will be needed for spider mites if you find 20-30% of the plants infested with 1-2 mites per leaf. If populations of mites have exploded and adult mites are the predominant life stage, Capture or Danitol should be used. If the population is a mixture of eggs, immature mites and lower levels of adult mites, Agri-Mek should be used at 8 oz/acre. A second miticide application may be needed in 3-7 days depending on the population level at treatment time. We are also starting to find a few melon aphids. The treatment threshold for aphids is 20% of the plants infested with at least 5 aphids per leaf. Fulfill, Lannate and Thiodan are labeled on melons and will provide melon aphid control. A penetrating surfactant (e.g. LI-700 or AD-100) should be used with Fulfill. Be sure to watch for bees foraging in the area and avoid insecticide applications on blooming crops. Be sure to follow all label restrictions regarding insecticide applications during bloom.

 

Peppers.

At the present time, all peppers that have fruit ½ inch in size or larger should be sprayed on a 7-day schedule for corn borer and pepper maggot control. A spray will also be needed for CEW as soon as trap catches begin to increase. Remember Orthene or Address will not provide satisfactory earworm control. A pyrethroid or Lannate will be needed for earworm control. A continuous pyrethroid program should not be used to avoid aphid explosions.

 

Snap Beans.

Seedling beans should still be watched carefully for leafhopper activity. The leafhopper threshold is 5 per sweep. Since corn borer catches are starting to increase, corn borer sprays should be applied at the bud and pin stages on processing snap beans. After the pin spray, sprays will be needed on a 5-day schedule until harvest. Since this can change quickly, be sure to check our website for the most recent trap catches and information on how to use this information to make a treatment decisions in processing snap beans  (http://www.udel.edu/IPM/traps/latestblt.html and our link to http://www.udel.edu/IPM/thresh/snapbeanecbthresh.html).  As soon as pin pods are present, fresh market beans should be sprayed on a 7-day schedule. Lannate, Capture,  Mustang or Warrior should be used.

 

Sweet Corn.

Fresh market silking sweet corn should be sprayed on a 3-4 day schedule throughout the state.   Be sure to check the IPM website for the most recent BLT catches in your area (http://www.udel.edu/IPM/traps/latestblt.html). We continue to find low levels of fall armyworm larvae in the latest planted corn. No controls will be needed until 15% of the plants are infested. Since fall armyworm feed deep in the whorls, sprays should be directed into the whorls and multiple applications are often needed to achieve control.

 

 

 

Vegetable Crop Diseases – Bob Mulrooney Extension Plant Pathologist; bobmul@udel.edu

 

Watermelon.

Be on the lookout for anthracnose on watermelons. Several samples have been diagnosed with anthracnose this week. The wet weather and favorable temperatures have been conducive for infection. Look for angular spots that can be limited by the veins on the leaves, but not always. Tan elliptical lesions can be found on the stems of wilting plants. Fruit symptoms are numerous, shallow depressions on the fruit with salmon colored spore masses on the lesions. See accompanying photos. Fungicide applications of 3 ptsA of Bravo plus 0.5 lb./A of Topsin are recommended on a 7-day schedule. Good coverage is very important especially to protect the fruit from infection.

 

 

Anthracnose lesions on watermelon leaf

 

 

 

Anthracnose lesions on watermelon stem.

 

 

 

 

Pickle and Lima Bean Situation Reports –

Ed Kee, Extension Vegetable Specialist; kee@udel.edu

 

Pickling Cucumbers – Situation Report

The USDA reports that U.S. processors have contracted 32% more than a year ago, with all states posting an increase, with the exception of Wisconsin.  Cucumber contract tonnage is at an all time high in 2003, totaling 53,600 tons.  In the chart below, Delaware and Maryland are included in “other states.”  Estimated acreage in our two states is approximately 7,500 to 8,000 acres.

 

Cucumbers for Pickles

Contracted Acreage

 

State	2003 Contract	2002 Contract	% Change
Indiana	2,100	1,600	31.3%
Michigan	27,000	22,000	22.7%
North Carolina	10,500	9,900	6.1%
Ohio	2,400	2,300	4.3%
South Carolina	4,200	3,900	7.7%
Texas	12,000	3,500	242.9%
Wisconsin	4,700	5,100	-7.8%
Other States1	38,900	31,500	23.5%
Total U.S.	101,800	79,800	27.6%

 

¹ – 2002 includes AL, CA, DE, FL, GA, MD, MA, MO, and WA

     2003 includes AL, CA, DE, FL, GA, MD, MA, AND MO

 

 

Fordhook Lima Beans – Situation Report

The national pack of Fordhook lima beans is expected to be lower this year, due to poor germination of California plantings and the closure of a California plant.  Over 90% of Fordhook production is in California.  As a result of the lower pack, prices for frozen product are expected to increase.  Current prices of 12/16 oz. cases of fordhook limas are around $13.75 per case.

 

The development of the ‘Sussex’ variety of Fordhook lima beans has shown promise for use in Delaware.  Research plots and several limited commercial trials have indicated it has the potential to yield competitively and produce high quality beans under Delaware conditions.  This year, two processors have nearly 375 acres planted, and if successful, they plan for more acreage in the future.

 

 

 

Field Crops

 

Field Crop Insects - Joanne Whalen, Extension  IPM Specialist;   jwhalen@udel.edu

 

Alfalfa.

Heavy potato leafhopper populations can still be found in many fields. Remember, once yellowing occurs damage has already been done and additional damage will affect the longevity of the stand. The treatment thresholds are 20 per 100 sweeps on alfalfa 3 inches or less in height, 50 per 100 sweeps in 4-6 inch tall alfalfa and 100 per 100 sweeps in 7-11 inch tall alfalfa.

 

Field Corn.

Continue to watch for Japanese beetles and corn rootworm adult beetles feeding on silking corn. The decision to treat should be based on the number of beetles per silk as well as how far you are in the pollination period. A treatment is recommended on silking corn if you can find 4-5 rootworm beetles per plant or 3 or more Japanese beetles per plant and they are clipping silks to less than ½ inch long before 50% pollination. Once brown silk is present, silk clipping will not affect ear fill.

 

Soybeans.

Heavy potato leafhopper populations and "hopper burn" can be found in seedling stage soybeans throughout the state. As a general guideline, a spray may be needed if you find 4 per sweep in stressed beans and 8 per sweep in non-stressed fields. There are no thresholds for numbers per leaf however, if leafhoppers are easily detected and you can see symptoms of plant damage, a treatment may be needed.  A pyrethroid or dimethoate will provide control.

 

Continue to watch fields carefully for soybean aphids. We have detected low levels of soybean aphids in New Castle County and Sussex Counties. If economic populations develop, timing of the insecticide application will be very critical. As a general guideline, treatment at flowering would be recommended if aphids are abundant on most plants, Current guidelines from the Midwest say treat if you find 25 or more aphids per leaflet. The following products are registered and have provided effective control:  Asana, Furadan, Lorsban, Mustang MAX , Penncap-M, Pounce and Warrior.

 

Continue to scout for grasshoppers and spider mites in seedling stage beans. Grasshopper populations remain high, especially in soybeans planted after barley and wheat. Grasshoppers can be controlled with Asana, Baythroid,  Dimethoate, Furadan, Lorsban or Warrior. We continue to find low levels of spider mites in an occasional field. Dimethoate, Lorsban or Parathion are the available products.

 

 

 

Grant Opportunities For Delaware Growers

 

Sustainable Agriculture Grants for Northeast Farmers

 

Farmers in the Northeast who are interested in conducting innovative production and marketing projects are encouraged to apply to the Sustainable Agriculture Research and Education (SARE) program for grant funds for projects starting in the spring.

Applications can address a broad range of agricultural issues such as pest management, soil and water conservation, aquaculture, marketing, grazing, bee health, no-till, pasture management, agroforestry, and other sustainable farming techniques. Northeast SARE defines sustainable agriculture as agriculture that is profitable, environmentally sound, and good for the community. In 2003, the average grant was about $5,200; grants are capped at $10,000.

Any full- or part-time farmer in the Northeast SARE region can apply. The region is made up of Connecticut, Delaware, Massachusetts, Maryland, Maine, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, West Virginia, and Washington, D.C. Applications and more information about the requirements of the Farmer/Grower Grant program are available on the Northeast SARE web site at www.uvm.edu/~nesar