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Foliar diseases, including Fabraea leaf spot and summer rots, should be managed to protect fruit as we approach harvest. FRAC 7 and 11 fungicides provide good control. Consider the pre-harvest interval (PHI) as we approach harvest. Also, read labels and consider restrictions on the number of applications for FRAC 7 and 11 fungicides. Topsin (FRAC 1) is also a good option for control with a 1-day PHI.

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.

Pear psylla populations have decreased compared to previous weeks. If adult psylla are present, 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).

Brown rot incidence remains low, but where fruit is present, rot has been observed (Figure 3). If you are harvesting fruit, this would be a good week to use one of your stronger single-site materials with a low PHI: Indar, Cevya, Orius, Quash, and Tilt (FRAC group 3); and Merivon, Luna Sensation, Pristine, and Quadris Top (FRAC group 11).

Figure 3. Brown rot on ripening peach fruit.

Oriental Fruit Moth (OFM) trap captures have decreased, and flight activity should be ending. Consider treatment if trap captures are above threshold (>8 moths per trap). A few options for late in the season with low PHIs would include Assail (7-day), Baythroid XL (7-day), Danitol (3-day), Delegate (1-day), and Sevin (3-day).

Japanese beetles are present in orchards and have been persistent this season, feeding in the tree canopy and on fruit. To prevent losses, include neonicotinoid materials such as Assail (7-day PHI), pyrethroids such as Baythroid (7-day), or premix products such as Leverage 360 (7-day). Verdepryn (IRAC 28, 7-day PHI) is also effective.

Figure 4. Lesser peachtree borer adult.

Scale crawlers are active in orchards. Options at this point include Assail, Belay (Group 4A), and the bioinsecticide Venerate. These products may provide some late-season suppression where fruit damage is observed. Venerate has a 0-day PHI, making it useful for blocks near or at harvest.

Brown Marmorated Stink Bug nymphs and adults are active and increasing in orchards. Late-season and pre-harvest control options include Assail (7-day PHI), Brigade (14-day), Danitol (3-day), Leverage 360 (7-day), and Venerate (0-day).

Lesser and greater peachtree borer trap captures continued to decline this week, although adults remain active, and egg laying is ongoing (Figure 4). Newly hatched larvae feed on the bark before boring into the lower trunk and root crown, where they overwinter and can weaken or kill trees. Growers should begin preparing for post-harvest trunk applications of pyrethroids (Asana or Pounce) or chlorpyrifos, with mid-August through early September generally providing the best timing to target young larvae before they enter the tree. Apply the insecticide thoroughly to the lower trunk, root flare, scaffold crotches, and any cankered areas, following label directions.

Average Trap Captures in Peach – Southern Counties

Average Trap Captures in Peach – Northern Counties

Spotted-wing drosophila (SWD) adults continue to be captured in monitoring traps (Table 1). SWD remains the primary target for insecticide applications.

Blueberry maggot is present, but is managed when controlling for SWD (Table 1). For management recommendations for SWD in blueberry and other berry crops, reference Rutgers Cooperative Extension Factsheet FS1246 and SWD Insecticides for Berries.

Table 1. Spotted-Wing Drosophila and Blueberry Maggot traps

Sharp-nosed leafhopper trap counts remain low (Table 2).

Oriental beetle adult flight activity continues to decrease (Table 2).

Table 2. Sharp-nosed Leafhopper and Oriental Beetle traps

Scales crawler activity of both terrapin scale and Putnam scale slightly increased (Table 3). Monitoring will continue throughout the fall to detect the emergence of the second crawler generation and determine the appropriate timing for pesticide applications. Continued monitoring will help ensure that management recommendations are based on current pest activity and that insecticide applications are made when crawlers are most susceptible. Scale infestations on fruit remain low (Table 4).

Table 3. Scale Traps

Table 4. Scale Infestation on Fruit

The IPM team continues to observe anthracnose and Alternaria. For recommendations on fungicide products, refer to the 2026 Commercial Blueberry Pest Control Recommendations for New Jersey or https://extension.rutgers.edu/sites/default/files/2026-03/bb-v42n01.pdf.

Weeds

Last week, the IPM team monitored 88 fields for weed pressure. The predominant weed species observed across production fields were nutsedge and goosegrass followed by marestail and barnyard grass. This was the last week for assessing weed pressure in the fields.  Based on current field conditions, postemergence herbicide selections should prioritize products with strong activity on annual grass species while considering the existing weed spectrum within individual fields. Refer to the 2026 Rutgers Blueberry Commercial Guide for management recommendations. 

Grape berry moth (GBM) continues to be captured in pheromone-baited traps in vineyards. Where populations have been managed, no further treatment should be needed, particularly as insecticide management shifts to other pests. Monitor for damage to bunches and consider treatment when 10% or more of the bunches show berry webbing and GBM larval feeding injury. See the Commercial Grape Pest Control Recommendations for New Jersey for management options.

Spotted lanternfly (SLF) adults are present in vineyards. As we approach September, adult migration into vineyards will increase, at which point we consider applying materials with long residual efficacy. See this previous Plant & Pest Advisory post on Management of Spotted Lanternfly in New Jersey Vineyards.

Spotted-Wing Drosophila trap counts continue to remain high in blueberries in southern counties. Monitoring efforts have shifted to grapes as veraison progresses and ripe fruit becomes vulnerable to infestation.

Grape root borer (GRB) adults are active and flying in vineyards. Monitoring traps indicate the presence of GRB in the area, but only scouting around the bases of vines will indicate the presence of GRB in the vineyard. Adult moths will lay eggs July-August. Larvae will enter the soil and migrate to the roots, where they feed and cause damage. Dr. Anne Nielsen and the IPM team will be monitoring vineyards throughout the state to assess GRB population pressure in NJ.

Grapes are beginning veraison in southern counties. Disease management continues to focus mainly on downy mildew (Figure 5), as well as powdery mildew, bunch rot, and black rot, but disease observations have been minimal. Refer to the NJ Commercial Grape Production Guide for more information on disease management options.

Figure 5. Downy mildew on the underside of a grape leaf.

• 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.

Pear psylla: Adult populations have decreased compared to previous weeks. If adult psylla are present, 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).

• 

  Figure 3. Declining peach trees due to environmental stress.

   

  Brown rot is appearing in ripening fruit throughout the state. Highly effective rot materials include DMI’s Indar, Cevya, Orius, Quash, and Tilt (FRAC group 3), and Strobilurin materials including Merivon, Luna Sensation, Pristine, and Quadris Top (FRAC group 11), which should be applied beginning 3 – 4 weeks prior to harvest.

• There have been reports of declining peach trees exhibiting yellowing foliage, gummosis, and bark splitting. Several samples have been submitted to the Rutgers Plant Diagnostic Laboratory. There has been one report of Cytospora canker and some insect borer injury observed, but overall the damage and decline have been attributed to weather extremes, including drought and significant fluctuations in temperature that have made certain varieties or trees in certain low-lying locations more vulnerable to abiotic stress, and insect and disease injury (Figure 3). The recommendation is to maintain proper irrigation and fertilization and prune out any visible cankers. Be mindful of pruning practices and avoid mechanical damage to trees to minimize injury.

Oriental Fruit Moth (OFM): A biofix point for OFM was set on 4/2 for southern counties and 4/15 in northern counties. See below for timings for the third generation. Consider treatment if trap captures are above threshold (>8 moths per trap).

Japanese Beetles: Japanese beetles have been observed feeding significantly on foliage and fruit. Products containing imidacloprid (Admire Pro, Leverage 360) are effective and may be warranted to protect fruit through to harvest.

Scale: Second-generation White Peach Scale crawlers should emerge sometime this week or next. Second-generation San Jose Scale crawlers emerge about 7/17 +/- 8 days. Esteem is a good scale material that has a 14-day PHI for stone fruit. Centaur is also effective, has a 14-day PHI, and can be used only once during the growing season. Venerate has shown efficacy as a pre-harvest treatment against scale and has a 0-day PHI. If using Venerate to control scale insects, make 2 applications 7 days apart, starting a week after crawler emergence.

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

Brown Marmorated Stink Bugs: Nymphs are active, and numbers continue to increase in orchards statewide. See the NJ Tree Fruit Production guide for effective materials.

Mites: Outbreaks of mites have been observed in a few orchards as a result of hot and dry weather from the previous week. If left unchecked, mites can build up to the point where leaf bronzing is visible by mid- to late July. If leaf damage is heavy enough, next year‘s crop can even be affected. Consider treatment if more than 10 mites per leaf are observed. Control options include Apollo, Savey, Envidor, Nealta, and Nexter. Try to limit miticide use to one application per material class per season.

Average Trap Captures in Peach – Southern Counties

Average Trap Captures in Peach – Northern Counties

Scouting was conducted last week across 75 conventional and organic blueberry fields in Burlington and Atlantic Counties. Monitoring of developing fruit indicated an overall decrease in pest activity, including feeding and oviposition by leafrollers, plum curculio, and cherry and cranberry fruitworms.

Aphids: Populations have declined significantly compared with previous weeks, likely due to recent weather conditions and the hardening of new shoot growth.

Spotted-wing drosophila: Trap captures slightly decreased in both Atlantic and Burlington Counties. SWD remains the primary target for insecticide applications (Table 1). For management recommendations for SWD in blueberry and other berry crops, reference Rutgers Cooperative Extension Factsheet FS1246 and SWD Insecticides for Berries.

Blueberry maggot: Adults are also present at low numbers, particularly in fields where picking and pesticide applications have slowed down.

Table 1. Spotted-Wing Drosophila and Blueberry Maggot traps

Sharp-nosed leafhopper: Trap counts remain low (Table 2). 

Oriental beetle: Adults are actively in flight (Table 2).

Table 2. Sharp-nosed Leafhopper and Oriental Beetle traps

Scales: Crawler activity of both terrapin scale and Putnam scale declined over the past week (Table 3). Monitoring will continue throughout the fall to detect the emergence of the second crawler generation and determine the appropriate timing for pesticide applications. Continued monitoring will help ensure that management recommendations are based on current pest activity and that insecticide applications are made when crawlers are most susceptible. Scale infestations on fruit also decreased last week (Table 4). For scale management, target the second generation of crawlers with post-harvest applications of diazinon or pyriproxyfen (Esteem).

Table 3. Scale Traps

Table 4. Scale Infestation on Fruit

The IPM team continues to observe anthracnose and Alternaria, likely associated with mechanical damage caused by picking machine activity.

For recommendations on fungicide products, refer to:

• the 2026 Commercial Blueberry Pest Control Recommendations for New Jersey
• https://extension.rutgers.edu/sites/default/files/2026-03/bb-v42n01.pdf

Grape berry moth (GBM): Third-generation GBM is actively flying and laying eggs. The next timing to apply control for GBM is 1620-1710 DD from the biofix date of wild grape bloom (5/19 for Gloucester County). As of July 20, we are currently at 1659 DD (base 47.14°F) in Gloucester County. Consult the Grape berry moth NEWA model for the most accurate forecasting for your area. Consider treatment when 10% or more of the bunches show berry webbing and GBM larval feeding injury. To determine the percent injury, examine 10 bunches on 5 vines in 4 locations. Often, the greenish-brown larvae can be found inside the berry. See the Commercial Grape Pest Control Recommendations for New Jersey for management options.

Spotted lanternfly (SLF): Adult SLF were observed in southern county vineyards this week (Figure 4).

Figure 4. Spotted lanternfly adult in vineyards in South NJ.

See this previous Plant & Pest Advisory post on Management of Spotted Lanternfly in New Jersey Vineyards.

Figure 5. Grape root borer pupal case at the base of a grape vine where the adult moth emerged.

Japanese beetle (JB): Pressure remains high throughout the state with considerable defoliation at some vineyards. See the NJ Commercial Grape Production Guide for more information on insecticides effective for JB.

Grape root borer (GRB): Adults are active and flying in vineyards. Monitoring traps indicate the presence of GRB in the area, but only scouting around the bases of vines will indicate the presence of GRB in the vineyard (Figure 5).

Adult moths will lay eggs July-August. Larvae will enter the soil and migrate to the roots, where they feed and cause damage. Dr. Anne Nielsen and the IPM team will be monitoring vineyards throughout the state to assess GRB population pressure in NJ.

• Botrytis has been observed in developing bunches.
• Incidence of downy mildew and powdery mildew has been low in NJ vineyards.
• See the NJ Commercial Grape Production Guide for more information on disease management options.