Archives for July 2017

July 12, 2017

BMSB is Under Attack!

Samurai wasp (Photo by Elijah Talamas)

Many of our fruit and vegetable growers throughout the state have been battling with populations of brown marmorated stink bug. This invasive pest feeds on most fruiting vegetables, small fruits, and tree fruits and can cause significant economic losses. One of the reasons that BMSB is such a bad pest is that when it arrived in the US, it did so without its co-evolved natural enemies. Until now! The Samurai wasp (Trissolcus japonicus) arrived in the US independently and the first populations were found in NJ in 2016 by the Department of Agriculture. However, no populations had been found in agricultural crops, which made us uncertain about its impact.

Last week, a parasitized egg mass was tentatively identified as the Samurai wasp. The Samurai wasp attacks stink bug eggs and has a special appetite for BMSB eggs. A female wasp will lay its eggs into the stink bug eggs. It is an effective parasite of BMSB and can parasitize on average 50% of each egg mass. Our finding was in a commercial peach orchard in southern New Jersey and may be the first finding in a US agricultural crop. We had placed egg masses in the orchard to measure natural enemy impacts of our border spray approach. We do not know the impact the Samurai wasp will have in NJ agriculture but this is a very promising new development in the fight against BMSB. Reduced spray methods, such as border sprays, may help to protect Samurai wasp populations in crops.

Samurai wasp emerging from BMSB egg mass

 

 

Drs. Joe Kaser and Clement Akotsen-Mensah contributed to this article.

 

 

Filed Under: Fruit, Uncategorized Tagged With: , , ,
July 12, 2017

Veg IPM Update: Week Ending 7/12/17

Sweet Corn
European corn borer (ECB) catches remain very low, and no map will appear in this edition.  Feeding in NJ sweet corn plantings is also low, with remaining larval infestations only on pre-tassel stage corn in the northern counties.  Check 5 plants each in 10 random locations for a 50 plant sample.  Look  for “shot-hole” injury, and  consider treating when the number of infested plants in a 50 plant sample exceeds 12%.  As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels.  Once plants hit full tassel, ECB larvae 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: Vegetable Crops Tagged With: ,
July 10, 2017

Potato | Tomato Disease Forecast 7-11-17

Click to View | Download Report 7-11-17

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: ,
July 10, 2017

Spotted Lanterfly

Have you seen this Insect?

Some people may think it is a moth but it’s really a plant hopper known as the spotted lanternfly, Lycorma deliculata (White) and is a member of the order Hemiptera, family Fulgoridae.

Spotted Lanternfly adult. Adults are about 1″ long

Its normal distribution is in eastern Asia, China, India, and Vietnam and has been found in Japan and South Korea. The adults are large (~1” long) and quite colorful with a black head, grayish black spotted forewings and reddish black spotted hind wings.

Young juveniles are black with white spots and as they get older they become red and black with white spots.

Spotted lanterfly nymph. Nymphs are black with red markings and white dots. Do not confuse them with BMSB nymphs which do not have spots and have white banding on the antennae.

Egg masses are brownish grey and generally laid on bark in early fall and appear like a smudge of mud. Egg masses are 1-1.5” long and ½ – ¾ “ wide and survive the winter.

 This insect was accidentally introduced into Pennsylvania and was confirmed in the state September of 2014. At first it was also found in Berks County, however, today it has been collected from Lehigh, Northampton, Bucks, Montgomery, and Chester County. Cities in these counties where Spotted Lanternfly has been found are currently under quarantine meaning that live Spotted Lanternfly and any material or object that can spread the insect cannot be moved from the quarantine area. Inspection of shipments for egg masses and subsequent removal may be an effective management tool if it becomes established in New Jersey. The Pennsylvania Department of Agriculture has a video series on egg mass scraping.

The spotted lanternfly is known to feed on more than 70 plant species including cultivated grapes, fruit trees, and hardwood trees. One tree of particular importance is Ailatus altissima (P. Mill) or the “Tree of Heaven”.

Tree of Heaven

Tree of Heaven typically grows in sunny areas along highways or disturbed habitat in clumps such as along farm edges. The Spotted Lanternfly must feed on Tree of Heaven to survive. Spotted Lanternfly has a sucking mouthpart and produces significant amounts of excess sugar from the plant sap, known as “honey dew”, during feeding. Honeydew can block sunlight absorption and reduce plant growth. We are concerned about this insect becoming established in New Jersey grape vineyards. In grapes, the honeydew produced during feeding is difficult to wash off and can reduce grape quality and perhaps growth. A 2015 and 2016 of 9 vineyards within southern New Jersey by the fruit entomology lab did not observe any spotted lanternfly adults or nymphs. However, in Pennsylvania, adults and nymphs were found in commercial vineyards in 2016 in Chardonnay, Concord, and Niagara plantings, although populations were low. Vineyard rows neighboring forested edges are at highest risk.

Egg mass

 

Additional information regarding this insect can be found at:

The Pennsylvania Department of Agriculture

Penn State Extension

 

If you think you seen or collected a spotted lanternfly please report it the New Jersey Department of Agriculture and the Department of Entomology at the Rutgers University School of Environmental and Biological Sciences by emailing slanternfly@njaes.rutgers.edu. This post was written by Anne L Nielsen and George C. Hamilton from the Department of Entomology.

Filed Under: Fruit, Uncategorized, Wine Grape Tagged With:
July 10, 2017

Root-feeding Pests of Cranberries

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. Occurrence of root-feeding insects will manifest by the presence of dead patches (see picture). Pull dead vines and search through the root zone and soil for grubs and worms. Admire Pro (imidacloprid) is labeled for the control of cranberry rootworm, white grubs (Phyllophaga spp.), and other scarabs in cranberries.

White grubs, Phyllophaga spp. There are several species of white grubs that infest cranberries in New Jersey, the most abundant being P. georgiana. Grubs are C-shaped and often found near bog margins. Adults are reddish brown and nocturnal. Grubs attack the cranberry roots; adults have not been reported to feed on cranberries. See pictures of grubs and grub damage in cranberries. The life cycles and abundance of white grub species in New Jersey is not well known. Most likely, Phyllophaga grubs have a 3-year life cycle (based on previous reports and our own observations). Eggs are laid in late-June and July, and will hatch in July. First instars can be found in late-July and August and turn into second instars by the end of August-September. The second instar grubs will overwinter. These grubs will feed the following year until June and molt to third instars, which will overwinter. The following year, the third instars will feed for some time and then begin to pupate in June. Pupation will take place in July-August. Adults will appear in the soil in August-September. Adults will remain in the soil and overwinter. They will emerge in June, mate, and begin to lay eggs, completing the cycle.

Phyllophaga grub damage

Cranberry rootworm (Chrysomelidae). Pupation starts in late May and beetles emerge in early June. Adults are nocturnal and hide in leaf litter. Adults can be easily picked up in a sweep net. Females feed on foliage before laying eggs. Young larvae will feed on roots, feeding continues until October. The mature larvae move down the soil in the fall to overwinter. Holding of the water will delay onset of pupation. Rootworm has a 1-year life cycle. Entomopathogenic nematodes (Heterorhabditis bacteriophora) can be used to control cranberry rootworm.

Use of Imidacloprid. If treatment is needed, use imidacloprid (Admire Pro or other generic insecticides such as Alias 4F) to control white grubs and rootworms. Imidacloprid works best against early- (1st-2nd) instar grubs. Imidacloprid should be used soon after bees are taken out of beds. Because of the 3-year life cycle, treatment should be continued for 2-3 consecutive years to ensure control. Imidacloprid (active ingredient) is a neonicotinoid insecticide registered for use in cranberries against cranberry rootworm and scarab grubs. This insecticide is a contact and stomach poison that affects the insect

Phyllophaga grubs, pupa, and adults

nervous system. It is highly systemic and toxic to honey bees; therefore, can be used only as a post-pollination insecticide. Imidacloprid can be applied by ground or by chemigation. Aerial application of this product is prohibited. Imidacloprid has a long residual activity (> 100 days) as long as the insecticide is not directly exposed to the sun. Admire Pro can be used at 7-14 fl oz/acre. A maximum of 14 fl oz of Admire Pro can be used per acre per season. The PHI is 30 days.

Phyllophaga life cycle

Filed Under: Cranberry, Fruit Tagged With:
July 7, 2017

Spotted Wing Drosophila (SWD) on Raspberries and Blackberries

A recent question from a raspberry grower in North Jersey asked about treatments for SWD on raspberries. The following table is from Cornell University – Greg Loeb, Laura McDermott, Peter Jentsch, Tess Grasswitz and Juliet Carroll, and published in the New York State Berry Growers Association newsletter: [Read more…]

Filed Under: Fruit