Search Results for: spotted lanternfly

July 18, 2018

Spotted Lanternfly in NJ

NEW PEST ALERT

Spotted lanternfly in grape

Spotted lanternfly in grape – photo credit E. Smyers

Spotted lanternfly (Lycorma deliculata, SLF) has been found in NJ. SLF is an invasive plant hopper species that could be very devastating to some NJ crops. Since its discovery in Pennsylvania in 2014, SLF has been placed under a state quarantine encompassing 13 Pennsylvania counties. Populations are also present in Virginia.

SLF adults and nymphs are phloem feeders that feed in large aggregations on woody tissue. Over 65 host plants were reported in Asia, many of which grow in the mid-Atlantic area. These host plants include hardwood trees such as Tree of Heaven, black walnut, and red maple and agricultural crops such as grape, apple, and hops. Feeding occurs on the trunk and limbs of plants, not on the fruit or leaf tissues. However, because they feed in aggregations and produce large amounts of honey dew (or sugar water), sooty mold can grow on plant surface and fruit, leading to reduced photosynthesis and plant vigor. In Pennsylvania, adults and nymphs have been observed feeding in commercial vineyards on cultivated grape. Economic estimates of injury are not available but growers report direct yield losses due to sooty mold and reductions in plant health and canopy coverage. Insecticides are effective but due to the high mobility of this pest, in highly infested areas, vines should be monitored closely for new bugs. Populations and injury are higher along vineyard edges, especially near Tree of Heaven. Interestingly, SLF tends to aggregate on a few trees or vines. Survey for SLF along the perimeters of fields and on Tree of Heaven, Black Walnut, Red Maple, and wild grapevines at the edges of wood lines. Aggregations of adults were found on commercial apple trees in PA near apples harvest in 2017, so apple growers need to be diligent as well.

The adults are large (~1” long) and quite colorful with a black head, grayish black spotted forewings and reddish black spotted hind wings. Adults may start to appear mid-late July (now) and will feed through the first hard freeze in the fall. Young nymphs hatch from eggs in late Spring/early summer and are black with white spots and as they get older they become red and black with white spots. While 4th instars have been reported in NJ, adults are present in VA, so be on the lookout for all life stages.

Spotted lanternfly on tree

Spotted lanternfly on Tree of Heaven – photo by A.L. Nielsen

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

Filed Under: Blueberry, Fruit, Landscape, Nursery, & Turf, Plant Diagnostic Lab, Tree Fruit, Uncategorized, Vegetable Crops, Wine Grape Tagged With: , , ,
June 17, 2021

Spotted Lantern Fly (SLF) in the NJ Vineyards – Survey

Dear Vineyard operator,

Rutgers Cooperative Extension in collaboration with NJ Center for Wine Research and Education (NJCWRE) is seeking your response regarding Spotted Lantern Fly (SLF) infestation and losses in your vineyard in previous years. Your responses are critical to understanding the distribution and impact of this invasive pest in New Jersey.  If you are unfamiliar with the spotted lanternfly or want to learn more about it, click here (https://njaes.rutgers.edu/spotted-lanternfly/). Please use the below link to fill out your responses.

The Survey Link: https://rutgers.ca1.qualtrics.com/jfe/form/SV_0OCjMZlaqXrOd6u

 

Filed Under: Wine Grape 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 7, 2026 , , and

Fruit IPM Report for Week of 6/29/2026

 

Apples
Disease Management Considerations
  • Bitter rot symptoms observed in southern and northern counties.
  • Hot, humid weather will increase the risk of fruit rots, including white rot, bitter rot, black rot, sooty blotch, and flyspeck.
  • Cultural control practices will help to minimize impact from disease in orchards: prune for improved air circulation, thin fruit clusters to reduce humidity and inoculum buildup, and cut out cankers that serve as inoculum sources.
  • Broad-spectrum fungicides, such as captan and ziram, are effective. Captan alone may not adequately suppress severe summer disease pressure.
  • Adding single-site products such as Merivon, Luna Sensation, Pristine, Omega, and Aprovia may improve control. The addition of phosphonate products such as ProPhyt or Rampart to captan sprays can improve control of rots and other summer diseases, including sooty blotch and flyspeck. It may help suppress scab infections when present.
  • Where fire blight is present, it is appropriate to prune out infected shoots. Do not cut out infections during wet weather, as bacteria can spread through water. The recommendation is to cut back to last year’s growth, at least 12” back into healthy tissue, and to sterilize pruners between cuttings.
  • Maintain coverage of captan, manzate, or ziram before rain events through the growing season according to the cover spray rule of applications every 2” of rain or 14 days, whichever comes first, to reduce the spread of foliar diseases, including Marssonina Blotch, Glomerella Leaf Spot, and Frogeye Leaf Spot. Foliar diseases can contribute to inoculum build-up in the orchard and significant defoliation of the canopy if left untreated.
  • Rainy seasons require tighter fungicide intervals to maintain coverage. Consider refreshing fungicide protection before major rain events.
Insect Update

Codling Moth (CM): On average, trap counts remain low in orchards across the state, with some numbers increasing at a few sites. Second-generation timings are updated below. Consider management if >5 moths are caught per trap or if fruit injury is observed (Figure 1).

Codling moth injury and larva in developing fruit.

Figure 1. Codling moth injury and larva in developing fruit.

Codling Moth Degree Day Timing – Second Generation
Application and Insecticide Type
County Area Biofix Rimon:

75-100DD + 14-17 days later

 

 Intrepid

1150 + 1450 DD

Diamides – Altacor, Voliam mixes: (150-200 DD)

 Madex

1250 DD + every 7-9 days during brood hatch (later if first spray is an IGR)

 Standard Insecticides –  Delegate, Avaunt, OP’s, carbamates, pyrethroids

1250 DD + 1550 DD

 
DD 1150 1450 1250 1250 1550
Southern April 20 N/A N/A past 7/10 past past 7/13
Northern  May 5 N/A N/A past 7/13 7/6 7/6 7/17

Scale: Crawler emergence continues, and injury has been observed on fruit in some orchards (Figure 2).

San Jose scale crawlers on apple.

Figure 2. San Jose scale crawlers on apple.

Control options during crawler emergence include Neonicotinoids (suppression only), Sivanto, Esteem, and Centaur. See also the scale discussion under the peach section.

Woolly Apple Aphid (WAA); Green Apple (Spirea) Aphids (GAA): Populations continue to build in some orchards statewide, but on average remain below treatment levels. A treatment threshold is set at 50% of the terminals infested with live colonies. Predation by lady beetles and other predators and parasitoids has been observed and can help to maintain pest populations below damaging thresholds. Scout in known hotspots for WAA colonies now. Minimize use of pyrethroids to manage insect pests, including Brigade and Mustang Max, which can flare pest populations and knock down beneficial organisms and predators. Movento will control WAA and GAA and can suppress scale when crawlers are active. Research from Dr. Monique Rivera at Cornell University has demonstrated good control from Sefina for WAA and can be considered instead of late Movento applications.

Potato leafhopper injury in new apple shoots.

Figure 3. Potato leafhopper injury in new apple shoots.

Potato leafhopper (PLH): Adults and nymphs are present and increasing in apple orchards throughout the state. Feeding damage from PLH results in “hopperburn” symptoms, which include browning & necrosis along leaf margins, along with leaf curling and stunting (Figure 3).

Consider treatment, particularly on young, non-bearing fruit trees. The preferred materials for leafhopper control include Actara, Admire, Assail, Belay, Endigo, and Voliam Flexi.

Ambrosia Beetle: Trap captures have been low in orchards across the state. Monitor for signs of stress or infested trees with “toothpicks” from boring activity and consider trunk sprays if needed.

Dogwood borer: Adult male moths caught in pheromone traps decreased significantly from previous weeks, indicating peak flight activity is coming to an end.

Traps

Average Trap Captures in Apple – Southern Counties

  Week STLM TABM CM OFM DWB AMBROSIA BEETLE BMSB
5/11/2026 18  11  6 3   25   2 –
5/18/2026 16 21 3 10   54 13 –
5/25/2026 1.3 23 2 2   71 7 –
6/1/2026 378 33 3 2   49 6 0.4
6/8/2026 258 11 2 1   61 21 1.2
6/15/2026 355 4 0.6 1.5   57 13 0.8
6/22/2026 178 5 0.6 2   54 8 1.2
6/29/2026 504 0.3 0.1 0.5   27 12 0.8

 

Average Trap Captures in Apple – Northern Counties

  Week STLM TABM CM DWB AMBROSIA BEETLE BMSB
5/11/2026 13.7 1.5 1.8 12.8 1.1 –
5/18/2026 8.3 13.25 2.4 18.5 10.8 –
5/25/2026 2.2 13.75 1.2 24.5 5.1 –
6/1/2026 25.1 24.3 3.4 23.8 9.4 0.3
6/8/2026  94 22.3 0.3 24.6  18 1.4
6/15/2026 68 22.3 1 22.6 14 1.1
6/22/2026 105.9 35 0.7 27.2 8.2 0.5
6/29/2026 100 11.5 0.3 28.9 5.3 0.3
Pears
Disease Management
  • Foliar diseases should be managed with Mancozeb or Ziram, plus a single-site fungicide, to maintain pressure and inoculum at low levels, protecting fruit and maintaining a healthy orchard going into the next season.
  • Where fire blight is present, it is appropriate to prune out infected shoots. Prune out strikes on dry, cooler days, cut back 8-12” back into healthy tissue, and sterilize pruners between cuts.
Insect Update
  • Pear psylla adult and egg stages are present in orchards where populations persist.
  • Options for control include Actara, Assail, and Belay (IRAC group 4A); Sivanto Prime (IRAC group 4D); Delegate (IRAC Group 5); and products containing abamectin (IRAC group 6). Other options include Movento (IRAC Group 23). The addition of 0.25-1 gal of summer oil may improve control. Avoid applying oil at high temperatures, and do not mix with captan. Be sure to read and follow the label instructions for adding penetrants to products.

Peaches
Disease Management
  • Brown rot can be found on developing fruit in southern NJ orchards (Figure 4).
    Brown rot on mature fruit.

    Figure 4. Brown rot on mature fruit.

    Growers should rely on a captan-based program for mid-season covers, followed by better materials during the last 3 weeks’ pre-harvest, where fruit is present and being harvested. See the New Jersey Commercial Tree Fruit Production Guide for more information.   

Insect Update

Oriental Fruit Moth (OFM): We are past the window to target the second generation.

Japanese Beetles: Japanese beetles have been observed feeding in orchards. Products containing imidacloprid (Admire Pro, Leverage 360) are effective and have a short preharvest interval.

Scale: Crawler emergence is active in orchards across the state. If crawlers are present, treatment options include Movento, Esteem, Centaur, Sivanto, and neonicotinoids (for suppression only). Movento and Esteem should be applied a week before or at the start of crawler emergence.

Thrips: Thrips injury has been found in orchards throughout the state (Figure 5).

Russeting on peach from early thrips feeding injury.

Figure 5. Russeting on peach from early thrips feeding injury.

Delegate or Entrust at the highest labeled rate are the usual recommended materials for thrips present in stone fruit. Time applications starting at petal fall to reduce injury. Lannate also has activity on thrips. These materials all have short PHI’s and may be applied close to harvest where thrips are observed.

Tarnished plant bugs and other catfacing insects: Insects are active, but new fruit feeding injury has been minimal.

Brown Marmorated Stink Bugs: Brown Marmorated Stink bugs are present at low to moderate levels and numbers are increasing from previous weeks in orchards statewide. Eggs are hatching and nymphs are present (Figure 6). See the NJ Tree Fruit Production guide for effective materials.

Lesser and Greater Peach Tree Borers: Male moth captures in pheromone traps decreased in number from previous weeks. Mating disruption is recommended to maintain low populations in your orchards.

Traps

Average Trap Captures in Peach – Southern Counties

  Week OFM TABM LPTB PTB BMSB
5/11/2026 5 10 – – –
5/18/2026 4 20 – – –
5/25/2026 2 20 31 1 –
6/1/2026 4 46 28 3 0
6/8/2026 8 13 25 3 0.75
6/15/2026 5 6 13 3 0.75
6/22/2026 6 4 23 7 1
6/29/2026 3 0.2 16 6 2

 

Average Trap Captures in Peach – Northern Counties

  Week OFM LPTB PTB
5/11/2026 4.4 24 0
5/18/2026 2.4 16.5 0.2
5/25/2026 0.7 8.75 0.1
6/1/2026 1.8 11 0.5
6/8/2026  0.6  8.5 0.05
6/15/2026 3.5 9.7 1.2
6/22/2026 3.4 7.4 1.6
6/29/2026 2 4.6 1.1

 

Blueberries
Insect Update

Scouting was conducted last week across 119 conventional and organic blueberry fields in Burlington and Atlantic Counties.

This week, the IPM monitoring team observed signs of cherry fruitworm infestation in developing fruit, although infestation levels remain low.

Aphids: Aphid populations remain low at an average of 1–5 aphids per shoot.

Spotted-wing drosophila & Blueberry maggot: Trap captures increased in both Atlantic and Burlington Counties for spotted-wing drosophila. An increase in blueberry maggot trap captures were observed in Atlantic County (Table 1).

Table 1. Spotted-Wing Drosophila and Blueberry Maggot Traps

Spotted-Wing Drosophila Blueberry Maggot
Atlantic County Burlington County Atlantic County Burlington County
Avg High Avg High Avg High Avg High
6/6 8.99 35 2.86 7 0.03 1 0 0
6/12 9.9 46 3.7 25 0 0 0 0
6/20 10.24 48 8.22 35 0 0 0 0
6/27 6.96 78 3.6 18 0 0 0 0
7/3 29.78 273 50.9 81 0.33 27 0 0

 

SWD remains the primary target for insect management. When selecting insecticides, special consideration should be given to products with shorter pre-harvest intervals (PHIs) that provide effective control of these pests while also helping suppress scale crawlers, aphids, and other pest populations above threshold levels. For more information, see the Blueberry Bulletin or Commercial Blueberry Pest Control Recommendations for New Jersey for recommendations.

Diseases

The IPM team continues to observe higher levels of anthracnose than in the previous week. The recent wet weather is conducive for anthracnose development on berries. Fungicide applications are still merited in fields where anthracnose has been reported. Phosphite materials are effective and have a 0-day PHI.

Additionally, mummy berry and Alternaria have been observed during scouting. The increased incidence of Alternaria is most likely associated with fruit injury caused by mechanical harvesting.

For fungicide recommendations, refer to the Rutgers Blueberry Commercial Production Guide or  https://extension.rutgers.edu/sites/default/files/2026-03/bb-v42n01.pdf

% Mummy Berry Infested Fruit % Anthracnose Infested Fruit % Alternaria Infested Fruit
Avg High Avg High Avg High
6/20 0.03 0.9 0.06 2.5 0.004 0.7
6/27 0.007 0.3 0.08 2.2 0.07 3
7/3 0.005 0.2 0.227 4.1 0.07 1.2

Grapes
Insects

Grape Berry Moth (GBM): Second generation adult GBM continue to be captured in pheromone traps and larval activity in bunches has been observed. The degree day timing to treat the second generation has passed. Second generation grape berry moth is not an automatic pest problem in New Jersey vineyards. The need for control is determined by examining bunches for larval activity, beginning in early‐July. An insecticide application is warranted when 5% of the bunches display larval feeding signs.

Japanese beetle: Japanese beetles are present in vineyards feeding on foliage. While established vines can tolerate some foliar injury, young or stressed vines are more susceptible to damage. If damage is severe, Assail, Baythroid, Belay, Danitol, or Sevin should provide the necessary control.

Spotted lanternfly: Population levels have been variable across the state, with average counts of nymphs remaining low compared to previous years. Fourth instars have been recently observed.

Diseases

Reports of disease incidence of downy mildew, powdery mildew, black rot, Botrytis bunch rot, and ripe rot have been minimal. Recommended materials can be found in the New Jersey Commercial Grape Production Guide.

Filed Under: Blueberry, Fruit, Tree Fruit, Uncategorized, Wine Grape Tagged With: , , , , , , , , , , , , , , , , , , , , , ,
June 5, 2026 , , , and

Vineyard Pest and Disease Management Considerations Following Freeze Injury

Vineyard Management Following Freeze Injury and Reduced Crop Potential
Reminders

Management programs this season should focus on preserving healthy foliage, minimizing inoculum buildup, and protecting any remaining harvestable crop. In New Jersey vineyards recovering from freeze injury, timing sprays appropriately and maintaining good canopy coverage will be especially important. 

Recommendations should always be adjusted based on vineyard history, cultivar susceptibility, weather conditions, and local scouting observations. 

Disease Management Following Freeze Injury 

Although immediate concerns following freeze events often focus on crop loss, freeze injury can substantially alter disease risk throughout the growing season. Even when crop potential is limited, disease management remains important. 

Phomopsis Cane and Leaf Spot
Phomopsis infections are favored by cool, wet conditions early in the growing season and can become established on shoots, rachises, and leaves shortly after budbreak. The disease becomes particularly important once flower clusters become visible, and grapevine tissues remain susceptible through berry set. In New Jersey vineyards, it is important to maintain fungicide protection during these periods. Maintaining good canopy airflow can also help reduce prolonged leaf wetness and disease development.  Mancozeb products can be used during the early season, provided the 66-day pre-harvest interval (PHI) is observed. After bloom, growers can transition to Ziram products with a 21-day PHI. Captan products may also serve as an alternative option for disease management.

Black Rot
Black rot management remains important with the remaining crop potential. Despite the freeze, this overwintering inoculum remains active and ready to infect new growth. The most critical control period for black rot is around bloom. This is important because berries naturally become resistant to black rot 4 to 5 weeks after bloom, meaning your spray timing window is narrow and critical. The first and second post-bloom sprays are the most important applications for black rot control. These sprays cannot be skipped if you want to protect any crops. Mancozeb applied before bloom provides good protectant activity. FRAC 3 fungicides, such as Rally and Mettle, combined with Ziram, are effective options for post-bloom black rot control. FRAC 11 fungicides like Abound are also effective but require careful management.  

Powdery Mildew
Powdery mildew is the most important fungal disease of grapevines. In freeze-damaged vineyards with reduced crop load, the focus of disease management shifts from fruit protection to maintaining leaf health. Severe defoliation from uncontrolled powdery mildew compromises vine recovery, making disease control important but requiring a different strategy. Rather than intensive fruit protection, growers should focus on reducing infections and limiting the overwintering inoculum for next season.  This provides flexibility to reduce the spray program from its usual calendar-based schedule. However, lateral shoots from secondary buds can cause dense growth, creating a perfect microclimate for powdery mildew. 

Sulfur is an excellent option for powdery mildew control, providing both preventative and curative activity. FRAC 3 (Demethylation Inhibitors) such as Rally 40WSP, Mettle 125ME, Inspire Super, and Quadris Top can be a good option for application in mid- to late-season to reduce the inoculum for next year. Other fungicides such as FRAC 11 (Quinone outside Inhibitors: Abound, Flint) can also be used. Newer chemistry options such as Quintec (FRAC 13), Torino (FRAC U6), and Gatten (FRAC U13) are also viable alternatives. However, you can stick with affordable options this year to keep costs down. The key is to maintain leaf health throughout the season. 

Growers should use caution with sulfur applications during periods of high temperatures or on sulfur-sensitive cultivars. 

Downy Mildew
Management of downy mildew in New Jersey vineyards requires regular scouting, especially after rain events and during periods of high humidity. Once the bloom is established, management becomes critical. If lesions appear, applying Captan can eradicate the disease and stop its spread. Scout again after two to three weeks to monitor effectiveness. Improving airflow through shoot thinning and canopy management is equally important, as it directly reduces the humidity that favors downy mildew development. Continue monitoring even in low-crop vineyards to preserve canopy function and vine health. 

Multi-site fungicides such as Captan and Ziram are effective in managing this pathogen. Phosphorous acid products offer curative activity for early-stage infections but have limited residual protection. If using Phosphorous acid products, Ziram can be added for longer protection. Copper products are effective where varietal sensitivity allows. For systemic control, Revus and Zampro are available options. Always tank mix or rotate these materials with unrelated fungicide groups to maintain effectiveness. 

Botrytis Bunch Rot
Botrytis presents a special challenge in freeze-damaged vineyards. Freeze-damaged tissues may increase susceptibility to infection. The risk increases during wet conditions between bunch closure and harvest. Botrytis primarily affects tight-clustered Vitis vinifera and hybrid cultivars, dense canopies due to lateral shoots, and delayed-ripening fruits on freeze-damaged vines, which can elevate risk.  Consider using Botrytis fungicide from FRAC groups (9, 12, and 17) during the bloom period. Importantly, tank mix any Botrytis material with either Captan or fixed copper to maintain resistance management and provide broader disease protection. Veraison, when berries begin to soften and ripen, is critical for timing protection. Some important management considerations include improving airflow and reducing cluster-zone humidity, carefully monitoring late-season weather conditions, and prioritizing protection in tight-clustered vinifera cultivars.  

Re-timing Your Spray Schedule
A standard “calendar-based” fungicide program, or a program based on fixed phenological stages, does not work in freeze-damaged vineyards. The reason is simple: uneven vine recovery leads to staggered growth. New growth remains vulnerable longer than expected in traditional vineyards. Not all vines reach the same growth stage at the same time. The standard spray timing developed for uniform vineyards misses the peak-risk periods in freeze-damaged blocks. 

The solution is to shift to phenology-based programs. Scout your vineyard regularly, at least weekly, from May to June. Identify where new secondary and tertiary shoots are emerging. Time your fungicide applications are based on the growth stage of most of your new growth, not calendar weeks. This approach ensures you are protecting the most susceptible tissue at the right time. 

 

REMINDERS 

Fungicide  Key Precautions 
Sulfur  Do not apply during hot weather (>85°F-90°F) due to phytotoxicity risk. Avoid use of sulfur-sensitive cultivars. Do not apply within 14 days of oil sprays—maintain at least a 14-day separation. May cause leaf burn on stressed or freeze-damaged vines. 
Copper  Can cause phytotoxicity, especially on sensitive cultivars. Increased injury risk under slow drying conditions or with repeated applications. Avoid mixing copper with phosphorous acid products. Excessive copper use may accumulate in soil over time. 
Mancozeb  Observe seasonal maximum application limits and monitor total lb. a.i./acre/year applied. Restricted by a 66-day PHI if the crop will be harvested. If it is a no-crop season, this restriction does not apply. Primarily a protectant fungicide; good coverage is essential for effectiveness. 
Captan  Avoid application during very hot weather or in slow-drying conditions. Do not mix with oils or apply near oil sprays. Can cause phytotoxicity on stressed vines, so use extra caution in freeze-damaged vineyards. 
Phosphorous Acid  Do not tank-mix with copper products due to the risk of phytotoxicity. Limited residual activity; may require shorter intervals or tank-mixing with protectant fungicides to maintain adequate protection. 

 

Young Vineyards May Require Additional Attention
Young or recently established vineyards may be particularly vulnerable following freeze injury because they have not yet developed extensive carbohydrate reserves within trunks and cordons. These vines are often located closer to the ground, where temperatures may be colder during frost events and may require additional monitoring throughout the recovery period. Severely injured young vines may recover slowly or, in extreme cases, require replacement. 

Weed Management Following Freeze Injury 

The goal during a low- or no-crop year is not to maintain a completely weed-free vineyard floor, but to reduce perennial weed populations, prevent annual weed seed production, manage excessive vine vigor, and prepare for the following season. 

Low crop years provide a unique opportunity to address persistent weed problems that are often difficult to manage during seasons with normal fruit production. With reduced concerns about immediate crop losses, vineyard managers can shift their focus from protecting current yield to improving long-term vineyard floor management and reducing future weed pressure. 

Prioritizing Perennial Weed Management
Perennial weeds should be the primary target during low-production years. Effective suppression of species such as mugwort (Artemisia vulgaris), field bindweed (Convolvulus arvensis), poison ivy (Toxicodendron radicans), multiflora rose (Rosa multiflora), Canada thistle (Cirsium arvense), or goldenrod (Solidago spp.) typically requires a multi-year management approach. A season with little or no crop presents an ideal opportunity to target these species when they are actively growing and most susceptible to control measures. Directed applications of systemic herbicides or repeated mowing may help reduce underground reserves and limit re-establishment in subsequent years. 

Rethinking Annual Weed Management
Unlike perennial weeds, annual weeds may not require complete season-long suppression during a low crop year. Moderate levels of annual weed growth within the row can provide some competition for water and nutrients, potentially helping to moderate excessive vine vigor that frequently develops when crop load is substantially reduced or absent. Excessive vegetative growth can increase canopy management requirements, reduce spray penetration, and create favorable conditions for disease development. For this reason, vineyard managers may be able to tolerate greater annual weed presence than would normally be acceptable in a full-crop season, provided weeds are prevented from producing seed. Mowing and mechanical suppression may therefore become more important management tools than repeated postemergence herbicide applications, particularly where annual weed populations are not interfering with vineyard operations. 

Preparing for the Following Season
Although some annual weed competition may be acceptable during the growing season, vineyard floors should be as free of weeds as possible by late summer and early fall. Clean vineyard rows improve the effectiveness of fall weed management programs and allow timely application of residual herbicides where appropriate. Reducing existing vegetation before fall applications can improve soil coverage and help establish a cleaner vineyard floor entering the 2027 growing season. 

Scouting and Mapping Problem Areas
Low crop years also provide an excellent opportunity to scout vineyards and document the location of troublesome perennial weed infestations. Mapping species composition and problem areas can improve future management decisions, facilitate site-specific applications, and help prioritize areas requiring more intensive intervention in subsequent seasons. Investments made in weed management during a low-production year can provide benefits that extend well beyond a single season.

Insect Management Considerations Following Freeze Injury

Insect management decisions should be based on remaining crop potential, vineyard history, and scouting observations. 

Where harvestable fruit remains, cluster-feeding pests such as grape berry moth should still be prioritized to preserve fruit quality and reduce population buildup for future seasons. Grape berry moth remains one of the most important cluster-feeding pests in New Jersey vineyards and may become concentrated on fewer remaining clusters in reduced-crop situations. 

Growers should continue monitoring for: 

  • Grape berry moth 
  • Japanese beetle 
  • Spotted lanternfly 
  • Mites 
  • Grape root borer where historically problematic 
  • Leafhoppers, mealybugs, and scale insects where historically problematic 

 

Regular scouting remains critical for identifying developing pest populations and determining whether treatment thresholds are exceeded. Recommendations emphasize the importance of local scouting information when making insecticide and fungicide decisions. 

 

Grape Berry Moth
Grape berry moth (GBM) pressure may vary considerably across New Jersey vineyards depending on surrounding wooded habitat, vineyard history, cultivar susceptibility, and remaining crop levels following freeze injury. Vineyards bordering wooded areas often experience greater pressure, particularly where wild grape hosts are present. In vineyards with reduced crop loads following freeze injury, clusters that remain may warrant protection to preserve fruit quality. 

Management considerations for New Jersey vineyards: 

  • Continue scouting vineyards and using pheromone traps to determine relative pest pressure and adult flight timings. Vineyards adjacent to wooded habitats are often at greater risk. 
  • Monitor clusters for webbing, frass, and larval feeding injury, particularly after peak moth flight periods. 
  • Time insecticide applications around egg hatch and early larval activity using regional degree-day models, scouting observations, and vineyard history. 
  • Using January 1 as a biofix, target the second generation at 1200–1400 degree days and third generation at 2100–2300 degree days (base temperature 47°F) when larval activity in bunches exceeds thresholds. 
  • Insecticides labeled in New Jersey grapes include products containing chlorantraniliprole (Altacor and generics), methoxyfenozide (Intrepid), indoxacarb (Avaunt), spinetoram/spinosad (Delegate, Entrust), Bacillus thuringiensis products, and pyrethroids such as bifenthrin and zeta-cypermethrin. Rotate modes of action to reduce resistance risk and always consult product labels for rates, timing, PHIs, and restrictions. 

 

Japanese Beetle
Japanese beetles can skeletonize grape leaves and may be especially problematic in young, newly planted, or freeze-stressed New Jersey vineyards during mid- to late summer. While established vines can tolerate some feeding, excessive defoliation may reduce vine vigor and limit canopy development needed for vine recovery and carbohydrate storage. 

Management considerations: 

  • Monitor vineyards from June through late summer, particularly along vineyard edges and in historically infested areas. 
  • Focus protection efforts on young vineyards, replants, and highly stressed vines, which are more vulnerable to excessive defoliation. 
  • Preserve canopy leaf area needed for vine recovery, particularly in vineyards affected by winter injury or freeze stress. 
  • Avoid placing Japanese beetle traps near vineyards, as traps may attract additional beetles and increase localized feeding pressure. 
  • Insecticide applications may be warranted when populations are high and defoliation threatens vine health. Products labeled in New Jersey grapes include materials containing acetamiprid (Assail), bifenthrin, zeta-cypermethrin (Mustang Maxx), carbaryl (Sevin), chlorantraniliprole (Altacor and generics), and imidacloprid. Always consult the product label for rates, timing, PHIs, and restrictions. 

 

Spotted Lanternfly
Spotted lanternfly (SLF) continues to be an important concern in many New Jersey vineyards. Heavy feeding by SLF can stress vines, reduce winter hardiness, and contribute to reduced vine vigor. Following the 2025–2026 freeze events, vines experiencing crop loss or environmental stress may be more vulnerable to additional injury from high SLF populations. While SLF can be found throughout vineyards, populations often begin along vineyard borders adjacent to wooded edges or preferred host plants. 

Management considerations for New Jersey vineyards: 

  • Continue monitoring vineyard borders and interior rows throughout the growing season, particularly near wooded edges and areas with known infestations. 
  • Scout regularly for nymphs and adults on trunks, cordons, and shoots, as well as honeydew accumulation and sooty mold. 
  • Remove or manage nearby tree-of-heaven (Ailanthus altissima) where practical, as it is a preferred host that can support local populations. 
  • Well-timed insecticide applications targeting other vineyard pests may also help suppress SLF populations. Products labeled in New Jersey grapes include materials containing bifenthrin, dinotefuran (Venom), thiamethoxam (Actara), carbaryl (Sevin XLR Plus), zeta-cypermethrin (Mustang Maxx), and phosmet (Imidan). Always consult the product label for rates, timing, PHIs, and restrictions. 
  • In vineyards with a history of high pressure, prioritize management when large numbers of SLF are present on vines to reduce additional vine stress. 

 

Spider Mites
Mite outbreaks are often associated with hot, dry conditions and may worsen in stressed New Jersey vineyards later in the season. 

Management considerations for New Jersey vineyards: 

  • Monitor leaves for bronzing and stippling 
  • Preserve predatory mites whenever possible and limit use of pyrethroids 
  • Avoid unnecessary insecticide applications that disrupt biological control 
  • Pay particular attention during hot, dry periods later in the season 

Regular scouting and preservation of beneficial arthropods remain key components of mite management in New Jersey vineyards. 

 

Grape Root Borer
Grape root borer is a variable pest across New Jersey vineyards, with some vineyards requiring yearly management while others experience little pressure. Vineyards with a history of grape root borer infestations may be at greater risk for winter injury and vine decline, as larval feeding on roots weakens vines and can increase susceptibility to environmental stress, including freeze damage. Larvae feed on grapevine roots, reducing vine vigor and, in severe infestations, may contribute to vine decline or death. 

Management considerations: 

  • Monitor vines for symptoms including reduced vigor, shortened shoot growth, small leaves, yellowing or wilting foliage, and reduced fruit production. 
  • Scout for empty pupal cases protruding from the soil around the base of vines from July through September, which indicate adult emergence. 
  • Eliminate weeds and excessive vegetation around the vine base to reduce favorable egg-laying sites and improve monitoring. 
  • Use mating disruption in vineyards with a history of infestations. Isomate GRB can help disrupt adult mating and reduce populations. 
  • In vineyards under chronic pressure, insecticides used on New Jersey grapes include products containing bifenthrin and chlorpyrifos. Applications should be timed to target adults and newly hatched larvae according to label directions and local emergence timing. Always consult the product label for rates, timing, PHIs, and restrictions. 

 

Mealybugs
Three mealybug species may be found in New Jersey vineyards: grape mealybug (Pseudococcus maritimus), obscure mealybug (Pseudococcus viburni), and Gill’s mealybug (Ferrisia gilli). Mealybugs feed on grapevines and excrete honeydew, which can lead to the development of sooty mold on leaves and clusters. More importantly, mealybugs are an important vector of Grapevine Leafroll–Associated Viruses (GLRaVs), which can reduce vine vigor, delay fruit ripening, and decrease fruit quality and yield. 

Management considerations for New Jersey vineyards: 

  • Monitor vines for white cottony masses under bark, at nodes, and around clusters, as well as honeydew and associated sooty mold. 
  • Scout for crawler activity, as crawlers are the most susceptible life stage for management. 
  • Remove and destroy heavily infested vines when practical to reduce virus spread. 
  • Manage ants when present, as they protect mealybugs from natural enemies. 
  • Avoid unnecessary broad-spectrum insecticide applications that disrupt biological control by predators and parasitoids. 
  • Preserve natural enemies, including lady beetles, lacewings, and parasitoid wasps, which can help suppress populations. 
  • When treatment is warranted, target the crawler stage for best efficacy. Products labeled for mealybug management in New Jersey include Movento, Applaud (buprofezin), Assail and generics (acetamiprid), Scorpion/Certador (dinotefuran), and azadirachtin products. Always consult the product label for rates, timing, PHIs, and restrictions. 

 

Continue Scouting and Targeting Inputs Carefully
Regular scouting remains especially important this season, as pest pressure and vine recovery may vary significantly between vineyards and even between blocks within the same operation. 

Careful monitoring can help growers: 

  • Identify developing disease outbreaks early 
  • Determine whether insect populations exceed treatment thresholds 
  • Prioritize sprays where crop remains 
  • Reduce unnecessary pesticide applications 
  • Improve timing and efficacy of needed treatments 

 

When sprays are necessary, maximizing coverage and application timing will be especially important to ensure each input provides the greatest benefit possible. 

Filed Under: Fruit, Wine Grape Tagged With: , , , , , , , , , , , , , , , , , ,
May 27, 2026 , , and

Fruit IPM Report for Week of 5/18/2026

Temperatures early in the week were hot, with highs in the low to mid 90s °F, before cooling later in the week and into the weekend, when temperatures hung in the mid to upper 50s °F. Cooler temperatures over the weekend were accompanied by approximately 1-2 inches of rain.

At this stage, surviving fruitlets are becoming easier to identify, although some additional drop is still expected in the next month. Growers are encouraged to continue evaluating blocks carefully before making management decisions throughout the season.

Despite reduced crop potential, continued monitoring and management remain important, particularly in blocks with surviving fruit or where maintaining tree health and supporting return bloom for the 2027 season are priorities. See the recent post from Rutgers Extension Specialists and Cooperative Extension on Managing orchards with through a season with limited yields.

Apples
Disease Management Considerations

Apple Scab: Primary scab season is approaching the end, or has ended. Any established lesions from the primary scab infection period can continue to drive secondary spread if not controlled. Recent wetting events can support disease spread, but the upcoming forecast is relatively dry, which should limit additional infection risk in the short term. Growers should continue to monitor conditions and maintain coverage with Mancozeb or Captan plus a single-site fungicide, particularly where primary infections may have occurred. Keep in mind that Mancozeb has a 77-day pre-harvest interval (PHI).

Cedar apple rust: Rust is active at this time. Even if you have a low to no apple crop, apple rust and scab still need to be managed. Maintain coverage with mancozeb until the end of May.

Powdery mildew: Leaves with powdery mildew were observed this week, and the risk for infection remains active under dry conditions (Figure 1). Mancozeb is not effective. In periods of hot days with high humidity and no rain, sulfur (e.g., Microthiol Dispers at 10 lb/A) can be applied. PM needs to be managed through July. Do not tank mix captan and sulfur.

Powdery mildew developing on leaves in apple. Photo by Sophia Solewater.

Figure 1. Powdery mildew is developing on the leaves of the apple. Photo by Sophia Solewater.

Fire blight: Symptoms began appearing in southern county apple orchards the week of 5/11. Products such as Apogee or Kudos are highly recommended to help slow the spread of infections. Repeated applications may be necessary to help control shoot blight from previous blossom infections or leftover cankers in the trees. It is recommended to cut out infected limbs 6–12 inches below the margin of visible infection. Ideally, infected tissue should be removed from the orchard and burned. However, if pressed for time, prunings can be left in the row middles to dry out and subsequently chopped with a mower. Do not cut out infections during wet weather, as bacteria can spread through water.

Rots: In orchards with fruit, management moving forward will focus on summer diseases, including fruit rots like bitter rot, sooty blotch, and fly speck. Broad-spectrum fungicides captan and ziram are effective, and adding single-site products such as Merivon, Luna Sensation, Pristine, Omega, and Aprovia may improve control. The addition of phosphorous acid products such as Prophyt or Rampart to captan sprays can improve control of rots and other summer diseases such as sooty blotch and flyspeck, and may help suppress scab infections where present.

Marssonina Blotch, Glomerella Leaf Spot, and Frogeye Leaf Spot: These diseases should be managed, as they will cause defoliation and provide a source of inoculum for black rot and bitter rot next season.  Maintain coverage of captan, manzate, or ziram prior to rain events through the growing season according to the cover spray rule of applications every 2” of rain or 14 days, whichever comes first.

Insect Update

Insect management programs should be adjusted this season to account for reduced crop load in many orchards. In blocks with little to no fruit, many early-season insect pests will not require treatment; however, monitoring should continue, and management should be maintained where pests threaten tree health or next year’s crop.

Rosy apple aphid: Activity has been very low to start this season. RAA can feed extensively on foliage and terminals, causing leaf curling and stunting. This can impact next year’s fruit that will be set this season. Without fruit, the trees may tolerate a higher threshold of these pests, but they should still be managed. Monitor for colonies during bloom and use a treatment threshold of 1 colony/tree at petal fall.

Woolly Apple Aphid (WAA); Green Apple (Spirea) Aphids (GAA): Aphid colonies are being observed in some apple blocks (Figure 2). WAA and GAA are generally pests that can be tolerated because they cause little direct damage. Treatment thresholds for WAA and GAA are met if 50% of the shoots are infested with no beneficial insects present. Movento will control WAA and GAA and should control scale when applied in mid-May, and suppress scale when applied in late May or early June.

Figure 2b. Green apple aphid colonies on younger branches.

Figure 2a. Woolly apple aphid colonizing pruned wood.

Ambrosia Beetle: Trap captures have decreased in southern NJ, indicating peak flight has ended or is coming to an end. In northern NJ counties, trap captures have been increasing with last week’s warm temperatures. Infested trees should be showing signs of stress or will soon. If you have had a history of this pest in your orchard, you should begin scouting for damage and flag any trees that have been attacked for continued monitoring.

Codling Moth (CM): Biofix has been set for southern counties as of April 20 and in northern counties as of 5/5. In blocks with little to no crop, CM management programs can often be reduced or delayed; however, monitoring should continue. Where mating disruption has been employed or there is a reduced insecticide program, supplemental Madex applications can be made at the timings listed below if the threshold exceeds 5 moths per trap per week.

Codling Moth Degree Day Timing
Application and Insecticide Type
County Area Biofix Rimon:

75-100DD + 14-17 days later

 

 Intrepid

150 + 450 DD

Diamides – Altacor, Voliam mixes: (150-200 DD)

 Madex

250 DD + every 7-9 days during brood hatch (later if first spray is an IGR)

 Standard Insecticides –  Delegate, Avaunt, OP’s, carbamates, pyrethroids

250 DD + 550 DD

 
DD 75 100 150 450 250 250 550
Southern April 20 Past Past Past 5/29 past Past 6/4
Northern  May 5 Past Past Past 6/4 5/21 5/21 Too far off

Leafhoppers: Adult leafhoppers typically begin appearing in apples this time of year. They appear as small, light-green, soft-bodied insects and are often found on the new leaves at the growing tips. High densities should not be tolerated in non-bearing orchards because they can stunt the growth of new shoots. They should also not be tolerated in orchards where fire blight is present, as they have been shown to spread the disease. Neonicotinoids are generally recommended for control; however, other broad-spectrum materials are also effective. 

Dogwood borer: Monitoring traps have captured high numbers of male dogwood borer adults, particularly in orchards with a history of the pest. Mating disruption is recommended and effective for this pest. Manage as needed in blocks with a history of infestation. Assail has demonstrated activity when targeting adults to reduce egg laying. See the 2026 Integrated Orchard Management Guide for Commercial Apples in the Southeast.

Traps

Average Trap Captures in Apple – Southern Counties

  Week STLM TABM CM OFM DWB AMBROSIA BEETLE
5/11/2026 18  11  6 3   25   2
5/18/2026 16 22 3 10   54 13

 

Average Trap Captures in Apple – Northern Counties

  Week STLM TABM CM DWB AMBROSIA BEETLE
5/11/2026 13.7  1.5  1.8   12.8   1.1
5/18/2026 8.3 13.25  2.4   18.5 10.8

Pears
Disease Management

Fabraea Leaf Spot: Spots have been observed on leaves in orchards (Figure 3). Infections can result in significant leaf spotting, defoliation, and unmarketable fruit. Foliar diseases should be managed with Mancozeb or Ziram, plus a single-site fungicide, to maintain pressure and inoculum at low levels, protecting fruit and maintaining a healthy orchard going into the next season. See the New Jersey Commercial Tree Fruit Production Guide for more information.

Fabraea leaf spot on foliage in pear. Photo by Katrina DeWitt.

Figure 3. Fabraea leaf spot on foliage in pear. Photo by Katrina DeWitt.

Insect Update

Pear psylla: Second generation pear psylla adults and eggs have been observed in southern counties. Pear Psylla are still actively laying eggs, and nymphs continue to hatch. Options for control include Actara, Assail, and Belay (IRAC group 4A); Sivanto Prime (IRAC group 4D); Delegate (IRAC Group 5); and products containing abamectin (IRAC group 6). Other options include Movento (IRAC Group 23). The addition of 0.25-1 gal of summer oil may improve control. Be sure to read and follow the label instructions for adding penetrants to these products.

Plum curculio; Stink bug; Tarnished plant bug: While activity during scouting may appear low, injury is being observed and may be more pronounced in orchards where reduced crop load is present. If high amounts of injury are observed and you intend to harvest the crop, consider a well-timed application of an IRAC Group 4A (Actara, Assail, and Belay).

Peaches
Disease Management

Given the widespread crop loss in many orchards, disease management programs should be adjusted accordingly. With little to no fruit present in most blocks, emphasis should shift away from fruit protection and toward maintaining tree health and reducing inoculum for next season.

Peach scab: In orchards without a history of high disease pressure, scab is generally not a concern in the absence of fruit. In blocks with a history of scab, lesions can still develop on current-season shoots and serve as inoculum for next year. In these situations, a reduced program may be warranted, with Captan applications timed ahead of significant rainfall events.

Bacterial spot: Leaf symptoms began appearing in orchards earlier in May. Leaf infections appear water-soaked, stay within the leaf veins, and gradually darken. Eventually, the chlorotic tissue abscises from the leaf, leaving a “shot-hole”. Copper injury appears similar. The main differences are that copper injury often appears at the leaf base, where the spray collects as it runs off, and the shot-hole will cross leaf veins. Copper injury often appears red at the margins of the shot hole. Fruit injury from bacterial spot results in dark lesions that are often accompanied by gummosis. Maintain low-rate copper programs to protect foliage and reduce inoculum for future seasons. Particularly important in blocks with a history of bacterial spot or under warm, wet conditions. Avoid combining copper with captan, especially following extended cloudy or slow-drying conditions.

Rusty spot and brown rot: Not a concern in blocks with little to no fruit. Fungicide applications targeting these diseases can be eliminated in most orchards this season unless there is a crop to protect. See the New Jersey Commercial Tree Fruit Production Guide for more information.

Insect Update

Insect management programs for peaches and nectarines should be adjusted this season due to reduced crop load. In blocks with little to no fruit, many fruit-feeding pests will not require treatment; however, monitoring should continue, and management should focus on pests that impact tree health or future production.

Oriental Fruit Moth (OFM): A biofix point for OFM was set on 4/7 for southern counties and 4/15 in northern counties. All treatments for the second generation have passed. We have seen very little flagging in new leaf tissue where OFM larvae have bored into.

Scale: White peach scale and San Jose scale crawlers begin to emerge at this time and will continue to emerge for up to 6 weeks. Control options during crawler emergence include Neonicotinoids (suppression only), Sivanto, Esteem, and Centaur.

Green Peach Aphid: Activity has been low to start this season, but is increasing with warmer temperatures. Examine trees for the presence of aphids by counting the number of colonies on ten trees and use a treatment threshold of 2 colonies/tree at petal fall for peach, and 1 colony/tree for nectarine. Management options include Assail, Actara, Admire Pro, or Sivanto.

Plum Curculio: Injury to developing peaches and apples has been observed in southern counties, with high infestation rates in orchards with a history of high pest pressure. Management for PC is not recommended at this time since adults are not currently active.

Tarnished plant bugs and other catfacing insects: Activity is increasing with dry weather and summer temperatures. Very little recent fruit feeding has been observed. In most blocks with little to no fruit, treatment is not necessary.

Lesser and Greater Peach Tree Borers: Growers using mating disruption for borer control should have them in place by mid-May. Even in orchards with little fruit, borers will need to be managed to maintain healthy tree stands for the next season. If this has been a historical pest in your orchard, mating disruption is recommended. Continue monitoring and managing as usual in problem blocks with mating disruption or trunk sprays.

Traps

Average Trap Captures in Peach – Southern Counties

  Week OFM TABM LPTB PTB
5/11/2026 5 10 – –
5/18/2026 4 20 – –

 

Average Trap Captures in Peach – Northern Counties

  Week OFM LPTB PTB
5/11/2026 4.4 24 0
5/18/2026 2.4 16.5 0.2

 

Blueberries
Diseases
Infected corolla tissue attached to developing fruit. Photo by Karlton Neidigh.

Figure 4. Infected corolla tissue is attached to the developing fruit. Photo by Karlton Neidigh.

During scouting activities this past week, low levels of Alternaria and Botrytis were observed on corolla tissue (Figure 4). Although disease incidence remained low, both pathogens were present in the field. Moving forward, fungicide programs should include products with activity against Anthracnose, Alternaria, and Botrytis. Anthracnose remains the primary disease concern at this time; however, given the recent weather conditions, an increase in disease development on corolla tissue still attached to the fruit would not be unexpected.

For management recommendations, refer to the Rutgers Commercial Blueberry Guide: https://njaes.rutgers.edu/pubs/publication.php?pid=e265

Insect Update

Scouting activities were conducted last week across 165 commercial and organic blueberry fields in Burlington and Atlantic Counties. Monitoring of leafrollers, spongy moth, plum curculio, and thrips shows an overall decrease in insect activity (Table 1) and corresponding injury to developing fruit (Table 2), most likely due to recent insecticide applications after petal fall.

 

Table 1. Beating Tray Sampling Data

Leafrollers Spongy Moth Plum Curculio Thrips
Avg High Avg High Avg High Avg High
4/17 0.0649 2 0.0001 0.1 0.0686 2.5 0.5547 9
4/25 0.0801 0.8 0.0001 0.1 0.1156 3 1.0383 26
5/1 0.1 0.8 0.0007 0.1 0.15 3 2.38 39
5/9 0.08 0.7 0 0 0.245 4.5 1.89 37
5/16 0.04 0.7 0.0007 0.1 0.117 3.5 5.02 99
5/23 0.006 0.3 0.0006 0.1 0.016 0.5 3.43 142

 

Table 2. Fruit Sampling Data

% Injury of Fruit by Leafroller % Injury of Fruit by Plum Curculio
Avg High Avg High
5/9 0.125 1 0.235 2.6
5/16 0.22 1.5 0.67 6.5
5/23 0.04 0.9 0.125 5.8

 

Plum Curculio: On average, scouts found 0.125 fruit with plum curculio scars per 10 bushes, with some fields reaching as high as 5.8 injured fruit per 10 bushes.

 

Aphids: Aphid activity has been detected in some scouted fields; however, colony sizes remain small, averaging 1–5 aphids per shoot (Table 3).

 

Table 3: Aphid Infestation on New Terminals

Aphids % Terminal Infestation
Avg High
5/23 1.5 14

 

Cranberry fruitworm and cherry fruitworm: Traps were checked last week. Activity was detected for cranberry fruitworm, while cherry fruitworm activity continues to increase, indicating that adults are still in flight and mating (Table 4).

 

Table 4. Fruitworm Trap Data

Cranberry  Fruitworm (AC) Cherry Fruitworm (AC) Cranberry Fruitworm (BC) Cherry Fruitworm (BC)
Avg High Avg High Avg High Avg High
5/1 0 0 2.5 5 0 0 3.5 7
5/9 0 0 4.4 6 0 0 6.25 10
5/16 0 0 7.7 11 0 0 9 15
5/23 0.14 1 5.14 15 0.25 1 16 29
AC: Atlantic County, BC: Burlington County

 

Scale insects: Traps were set to monitor Putnam scale and terrapin scale. Scales in the crawler stage are beginning to become active (Table 5).

 

Table 5. Scale Insect Trap Data

Putnam Terrapin
Avg High Avg High
5/23 36.85 230 1.8 8

Management recommendations can be found on the current Blueberry Bulletin and Commercial Blueberry Pest Control Recommendations for New Jersey.

Grapes
Grape Phenology

Grape development across New Jersey has progressed, with most vineyards in southern counties moving through to pre-bloom, depending on variety and site conditions.

Damage is most apparent in low-lying or frost-prone sites, where primary shoots may have been injured or killed. In these situations, secondary buds are beginning to push and may help compensate for some crop loss, though overall yield may still be reduced depending on the extent of primary bud injury.

At this stage, vineyards should be assessed for primary and secondary bud viability and uniformity of growth. Blocks with uneven development may require adjustments in management timing over the coming weeks.

Concord grapes were recorded in bloom on 5/19.

Diseases

The most important diseases to manage at this time are Phomopsis, black rot, downy mildew, and powdery mildew. More information on early-season disease control can be found in this blog post by Dr. Mizuho Nita at Virginia Tech. Recommended materials can be found in the New Jersey Commercial Grape Production Guide.

Insect Update

Insect pests to monitor are the grape flea beetle and the climbing cutworms. Controls for these insects are rarely needed. Spotted lanternfly nymphs are emerging in southern counties and will continue to hatch over the next few weeks. Insecticide applications are generally not recommended to control SLF nymphs. Due to the April freeze, the vines are under stress; therefore, a well-timed insecticide application to manage other key pests can knock down nymph populations.

Grape berry moth: Adults continue to be trapped in pheromone traps in vineyards where there is surrounding pressure from wild grapes. Insecticide timings will target control of later generations of grape berry moth in vineyards infesting developing fruit bunches. Using January 1st as a biofix, insecticide timing to target second generation will be 1200-1400 DD base 47°F. Use the NEWA model for grape berry moth to inform management timing for local populations, and refer to the Commercial Grape Pest Control recommendations for New Jersey.

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