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

Fruit Crops Edition - Wine Grape Section

Seasonal updates on diseases, insects, weeds impacting small fruit (blueberry, cranberry, and wine grape). Fruit Pest Alerts are also available via this category feed.
 
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July 26, 2017

Grape Root Borer – Do I Need to Treat?

Dean Polk, Statewide Fruit IPM Agent and Dr. Anne Nielsen, Extension Specialist in Fruit Entomology

A number of growers have recently asked about treatments for grape root borer. Grape root borer (Vitacea polistiformis Harris) is a comparatively large clearwing moth. The adults can resemble Polistes wasps, and can often be confused with these insects, especially since it is often easier to see a wasp in a vineyard than an adult grape root borer. See the images that compare the 2 insects below in Figure 1.

Figure 1. Polistes wasp on left, compared to male grape root borer on right. Credits Hermann 2012 and Copeland 2012.

One important difference is that grape root borer (GRB) larvae feed inside grape roots, while wasp larvae do not. Although the grape borer is more of a southern pest, it is present in New Jersey and can be a pest that does significant damage. Adult females lay eggs on the vine surface and on weeds near the crown. Shortly after hatching the larvae enter the crown and central root system, boring into the roots where they can last for 2 years. When the larvae mature, they exit the wood and pupate close to the soil surface where they emerge from early July through August. GRB is not considered an economic pest until about 5% of the vines are infested. This is determined by examining the bases of numerous vines at weekly intervals for signs of adult emergence, or pupal cases (exuvia), throughout the summer, see Figure 2. Pheromone traps can also be used to measure adult emergence, but since they attract moths from both the surrounding woods and vineyards, they are practically useless to tell us what is going on in any specific vineyard. Counting pupal cases is labor intensive, but does tell us if the vineyard is or is not truly infested.

Figure 2. Pupal case from newly emerged adult GRB.

 

During 2015 -’16 we monitored 2 plantings at each of 9 vineyards. During that time we found 3 vineyards that had populations of GRB that merited treatment, or were above the 5% infestation level. While infestation levels can change over time, this does tell us a few things about GRB in NJ. First, about 33% of the vineyards we sampled had economic populations of GRB. Therefore growers need to determine if they indeed have GRB populations that merit treatment prior to actually doing a GRB treatment. Secondly most GRB adults emerged from the soil a little later than we first thought. Counting the pupal cases over time, we can get an emergence curve as in Figure 3. This vineyard does merit treatment, since the total vines infested is over 5%. Most of the insects that emerged peaked in late July and early August.

Figure 3. GRB exuvia counts over time Farm A, 2015, ’16.

Treatments: If the vineyard has an economic population, then the standard treatment would be using Lorsban at the start of adult emergence, which would be now in most years. The material is applied to the soil around the base of each vine, and forms a barrier that kills young larvae as they burrow into the soil and root system. Growers can use any of several formulations. The rates vary depending on the formulation that is used. Lorsban Advanced: Use 4.5 pt/100 gal, with 2 qt applied to a 15 sq ft area around each vine; Lorsban 4E: Use the same amount as with the ‘Advanced’; Lorsban 75WG: Use 3 lb/100 gal, with 1.5 qt applied to 11 sq ft around each vine. There is a 35 day PHI with Lorsban products for grapes. Do not contact the fruit surface, and apply only to the soil at the base of each vine.

Filed Under: Fruit, Wine Grape
July 13, 2017

Fruit IPM for 7/13/17

Peach:

Oriental Fruit Moth (OFM): The 3rd OFM flight is well underway in all counties. These adults produce 3rd brood of larvae, which primarily infest the fruit.

[Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape
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 7, 2017

Getting the Upper Hand on Virginia creeper

Picture 1 – Virginia creeper vine

Virginia creeper (Parthenocissus quinquefolia) is a perennial woody vine that climbs on other objects or trails along the ground.  It is a common weed of orchards, vineyards and blueberry plantation. It is best identified by the typical palmate leaf with 5 leaflets that originate from the same point (picture 1).  Virginia creeper will produce many tendrils with adhesive disks at their tips that will allow the vine to climb upward and to attach to any support. It can grow under a wide range of conditions including dry sandy or moist organic soils, sunny or shady sites, and is tolerant to high salinity.  Plants will often establish through seeds dropped by birds who consumed the small blue berries in fall, but also by the spread of crawling stems that will produce new roots in contact with soil (picture 2). Virginia creeper is often confused with Poison-Ivy (Toxicodendron radicans). However, poison-ivy has 3 leaflets instead of 5 for Virginia creeper and lacks the tendrils and adhesive disks.

As a perennial weed, Virginia creeper will be tough to control as it can easily regrow after foliar injury from its extensive underground root system. When established, Virginia creeper will most often not be controlled with a single herbicide application, and multiple applications will be necessary to achieve acceptable control. Only nonselective postemergence herbicide (glyphosate) must be used to suppress or control this weed. In order to increase the efficiency of postemergence applications during the growing season, remove the vine from their support during winter pruning and lay it on the ground or plan a “cut stump” treatment during the growing season. Do NOT “prune out” the vine during the dormant season.

Picture 2 – Virginia creeper rooting stem

Spot treatment.  Glyphosate may be applied in mid- to late summer after vine flowers in early July until the first signs of fall color appear in the foliage. Good growth and maximum leaf area is needed at the time of herbicide application during the summer.  Wet a minimum of 50 percent of the weed foliage with a 1% glyphosate solution (1.25 oz of 4.5lb acid material per gallon of water) for effective control. For best control, don’t apply on stressed/wilted weeds.

Cut stump treatment. Best results are often obtained in late summer and early fall, but before fall color is observed in the foliage. Apply a 1% glyphosate solution to the cambial areas (inner bark area) of the stump of woody plants IMMEDIATELY after cutting. Cut and treat stumps only when the Virginia creeper is actively growing and not under stress.

WARNING. Injury due to root grafting may occur in adjacent plants. Do not treat cut stumps if there is a possibility of root grafting to desirable vegetation. Do NOT allow contact with green bark, trunk wounds, leaves, or root suckers of blueberry bushes.

The mention of trade names and rates is for educational purposes and does not imply endorsement by the author or the New Jersey Agricultural Experiment Station. Always defer to the product label for instructions on properly applying an herbicide.

Filed Under: Blueberry, Cranberry, Fruit, Strawberry, Tree Fruit, Vegetable Crops, Wine Grape Tagged With: , , , ,
June 21, 2017

Fruit IPM for 6/21/17

Grape:

Grape Berry Moth (GBM): The timing for second generation treatments in Gloucester County and surrounding areas will be on 6/21 to 6/22. Grape berry moth is the most common insect in NJ vineyards that will directly damage the fruit (See Figure 1.) This timing is for the use of Intrepid, Altacor, and Delegate. If you are using other products like Danitol, Baythroid, Brigade, or Imidan, then you can make the application a few days later. This timing is calculated for 810 degree days (base 47) after wild grape bloom, which was May 16.

[Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape Tagged With: , , ,
May 19, 2017

2017 Wine Grape Twilight (North and South Jersey)

North Jersey:  May 23, 5:30 PM @ Terhune Orchard Winery, 330 Cold Soil Rd, Princeton, NJ 08540

South Jersey:  May 24, 5:30 PM @ White Horse Winery, 106 Hall St, Hammonton, NJ 08037 [Read more…]

Filed Under: Fruit, Tree Fruit, Wine Grape Tagged With: , ,