Fruit IPM Updates Week of 4/27/2026

Tree Fruit Phenology Update

Tree fruit development across New Jersey continued to progress over the past week, and the impacts of the recent freeze event are now becoming more clearly defined. Across much of the state, significant injury to blossoms and young fruit has been confirmed, with many orchards reporting substantial crop loss. The extent of damage remains highly variable by location, elevation, variety, and phenological stage at the time of the freeze, with the most severe injury observed in low-lying areas and blocks that were at full bloom or petal fall.

At this stage, surviving fruitlets are becoming easier to identify, although some additional drop is still expected over the coming week. Growers are encouraged to continue evaluating blocks carefully before making final management decisions, as crop potential may continue to change.

In apples, early varieties such as ‘Pink Lady’ sustained significant injury in many locations. However, some later-developing blooms appear to have escaped the freeze, and limited fruit set is being observed from these later flowers. While this provides some promise in select blocks, overall yield potential remains extremely low across most orchards. Variability remains high even within individual blocks.

In pears, most varieties across the state were at or just past bloom during the freeze, and widespread crop loss has now been confirmed. In many orchards, little to no viable fruit remains, though isolated pockets of surviving fruit may still be present depending on site conditions.

Peach and nectarine varieties in southern counties, which were at petal fall to early shuck split during the freeze, experienced extensive crop loss in many orchards. In northern counties, where bloom was still ongoing at the time of the freeze, damage remains variable but is often substantial in more exposed locations.

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.

Apples
Apple Phenology Update

Apple phenology continued to progress across New Jersey over the past week, with most blocks now moving through bloom into petal fall. The impacts of the recent freeze event are now becoming more apparent, with significant injury observed in many orchards statewide. Early varieties in southern counties, such as ‘Pink Lady,’ sustained substantial damage where they were at full bloom during the freeze.

Later varieties and more northern regions show variable levels of injury depending on bloom stage and site conditions. In some blocks, later-developing blooms appear to have escaped damage and are setting limited fruit. Surviving fruitlets are becoming easier to identify, although some additional drop may still occur over the coming week.

As development continues into petal fall and early fruit set, this remains a critical period for disease management, particularly for fire blight, apple scab, powdery mildew, and cedar apple rust. Even in blocks with reduced crop, maintaining protection of foliage and any surviving fruit is essential for overall tree health and to support return bloom next season. Monitoring for early-season insect pests should also continue, with management decisions adjusted based on crop presence and block-specific conditions.

Phenology Dates by County (earliest varieties)

County Green Tip Tight Cluster Pink Bud Bloom Petal Fall
Cumberland 3/22 3/28 4/3 4/8 4/17
Gloucester 3/22 3/28 4/3 4/8 4/17
Burlington 3/22 3/28 4/2 4/13 4/22
Mercer 3/22 3/28 4/2 4/13 4/22
Middlesex 3/22 4/1 4/4 4/14 4/22
Monmouth 3/22 4/1 4/4 4/14 4/22
Hunterdon 3/22 4/1 4/10 4/17 4/24
Morris 3/26 4/4 4/11 4/17 4/24
Warren 3/30 4/4 4/13 4/17 4/24
Sussex 3/31 4/10 4/14 4/18 4/24
Bergen 3/22 4/1 4/4 4/14 4/24
Apple Scab
Apple scab season is approaching the end of primary ascospore release, with most ascospores now matured and a large proportion already discharged. We are transitioning out of peak primary infection risk; however, recent infection events and any established lesions can continue to drive secondary spread if not controlled.Recent wetting events earlier this week resulted in infection periods, but the upcoming forecast is relatively dry, which should limit additional infection risk in the short term. Growers should continue to monitor conditions closely and maintain coverage, particularly where primary infections may have already occurred. Models are available through NEWA and RIMpro
Current Update using the Upper Deerfield Station
  • ~91–94% ascospore maturity as of April 29–May 1
  • ~62–63% cumulative ascospore discharge to date
  • Forecasted to reach ~95–98% maturity by May 2–6
  • Cumulative ascospore discharge forecasted to increase to ~73% by May 2–6
  • Infection events occurred April 29–30 under sufficient wetting and favorable temperatures
  • Limited infection risk is forecast over the next several days due to dry conditions

While primary scab season is nearing completion, remaining ascospores and recent infection events mean that protection should be maintained until discharge is complete and orchards are scouted for lesions.

Management Considerations

Fungicide programs should be maintained through petal fall and early fruit set, particularly in blocks where infection events occurred this week. However, as primary scab season nears completion and ascospore maturity approaches full discharge, growers should begin planning to wind down intensive scab programs.

One additional well-timed fungicide application over the next week may be sufficient to protect against any remaining ascospore release and recent infection events. Following this, programs can be adjusted based on scouting and the presence or absence of lesions.

Despite widespread freeze injury, protecting foliage remains critical for tree health and return bloom. Programs should continue to prioritize apple scab until primary season is complete, along with powdery mildew and cedar apple rust. Fire blight protection should continue where bloom or trauma blight risk remains.

Recommended Programs

  • Final primary scab spray (next 5–7 days):
    • Mancozeb or Captan + single-site fungicide (use reduced rate when tank mixing)
    • Time this application ahead of any remaining wetting events to protect against final ascospore discharge
  • Primary scab season is nearing completion — begin transitioning out of intensive spray programs
  • One final fungicide application over the next week should be sufficient in most blocks to cover remaining ascospore discharge
  • Recent infection events occurred April 29–30 — ensure coverage was adequate and consider follow-up where needed
  • After this final application, shift to scouting for primary lesions and adjust programs accordingly
  • Do not fully relax programs where foliage health is still a priority, especially in blocks with any remaining crop
  • Powdery mildew remains active under dry conditions
  • Do not tank mix Captan with oil due to phytotoxicity risk

Fireblight

Models

Fire blight risk remains present as we move through the end of bloom and into early post-bloom, particularly in blocks with open blossoms or where freeze injury may have created additional infection sites. Recent conditions included wetting events on April 29–30; however, risk has been relatively low over the past few days.

Forecasts indicate increasing risk heading into early next week, with Cougarblight values rising and infection potential (EIP) expected to increase by May 5–6 under warmer conditions. These conditions may support infection if bloom remains or if trauma events occur.

Given the current outlook, one to two additional bactericide applications may be warranted, particularly in blocks with a history of fire blight, open bloom, or high-value varieties. Applications should be timed ahead of forecasted rain events where possible.

Management Considerations

  • Consider 1–2 additional sprays.
    • Particularly important in blocks with open bloom, recent freeze injury, or known fire blight history
    • Time applications ahead of forecasted wetting events
  • Rotate bactericides.
    • Streptomycin, Kasugamycin, and Oxytetracycline should be rotated to reduce resistance risk
    • Kasumin is labeled through bloom/petal fall only
    • Streptomycin and oxytetracycline may be used post-bloom (FireLine 45 allows only one post-bloom application)
  • Monitor models closely.
    • Use Cougarblight and EIP tools to guide timing
    • Enter your last streptomycin application date to improve model accuracy
  • Be aware of trauma blight risk.
    • Freeze injury, wind, or hail can create entry points for infection even after bloom
  • Plan for aggressive sanitation this season.
    • With reduced crop in many blocks, this is an ideal year to focus on removing infected wood
    • Prune out blighted shoots and cankers during dry conditions to reduce inoculum for future seasons

Monitor:

    • NEWA models
    • Weather/wetting events
    • Phenology
Insect Update

Insect management programs should be adjusted this season based on 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.

  • Ambrosia Beetle
    • No new significant flight activity has been observed in recent days
    • Peak flight period appears to have passed, though low-level activity may still occur
    • Continue monitoring traps, particularly in stressed, freeze-damaged, declining, or newly planted blocks
    • Freeze-injured trees may remain attractive, so risk is not fully eliminated
    • No additional insecticide applications are needed in most blocks at this time unless activity resumes or trees are under stress
  • Codling Moth (CM)
    • Biofix has been set for southern New Jersey as of April 20, 2026
    • In blocks with little to no crop, CM management programs can often be reduced or delayed, as the risk of economic injury is low; however, monitoring should continue.
    • Mating disruption should remain in place where already deployed; do not remove dispensers, as they will continue to suppress populations
    • 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 threshold exceeds 5 or more 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 5/4 5/5 5/11 Too far off Too far off Too far off Too far off
Northern  NA NA NA NA NA NA NA NA
  • Other Apple Insects
    • In blocks with little to no crop, many early-season fruit-feeding insects will not require treatment at this time. Continue monitoring, and focus management on pests that impact tree health, terminal growth, or future crop potential.
  • Plum curculio, tarnished plant bug, stink bugs, BMSB, TABM, and OBLR:
    • In most blocks, treatment is not necessary where little to no fruit is present
  • Mites:
    • Continue to use standard thresholds through June
    • Maintaining healthy foliage is important for return bloom next season
  •  Rosy apple aphid:
    • Manage only in cases of severe infestation to avoid excessive leaf curling and shoot distortion
  • Dogwood borer:
    • Manage as needed in blocks with a history of infestation
Summary
  • The recent freeze has resulted in widespread blossom and fruit loss across many orchards, with damage now becoming more clearly defined at the block level
  • Some late-developing apple blooms have escaped injury and are setting limited fruit
  • Apple scab season is nearing completion, with most ascospores matured and a large portion already discharged; one final well-timed fungicide application should be sufficient in most blocks
  • Fire blight risk remains in blocks with open bloom or recent injury; 1–2 additional bactericide applications may be warranted based on model predictions and weather conditions
  • Insect management programs can be reduced in many blocks due to low crop, but monitoring should continue and management maintained for pests that impact tree health
  • Maintaining healthy foliage and overall tree vigor remains critical to support return bloom and production for the 2027 season

Pears
Pear Phenology Update

Pear development continued to progress across New Jersey over the past week, and the impacts of the recent freeze event are now becoming more clearly defined. Significant injury to blossoms and young fruit has been confirmed across much of the state, with many orchards reporting substantial crop loss.

Most European pear varieties were at full bloom to early petal fall during the freeze and have sustained widespread damage, particularly in low-lying or frost-prone areas. In many blocks, little to no viable fruit remains, though isolated pockets of surviving fruit may still be present depending on site conditions.

Asian pear varieties, which were generally more advanced at the time of the freeze, appear to have experienced even greater levels of injury in some locations. In northern counties, where bloom was still ongoing, damage remains variable but is often still substantial in exposed sites.

At this stage, surviving fruitlets are becoming easier to identify (Figure 2), although some additional drop may still occur over the coming week. Growers should continue to assess blocks carefully before making final management decisions.

Pear fruitlets cut to assess freeze injury—internal tissue appears viable; however, additional drop may occur. Salem County, NJ.

Figure 1. Pear fruitlets cut to assess freeze injury—internal tissue appears viable; however, additional drop may occur. Salem County, NJ.

Despite reduced crop potential, maintaining disease management and overall tree health remains important, particularly to support return bloom and long-term productivity.

Pear Psylla
  • Pear psylla activity remains low across much of southern New Jersey, with limited observations to date
  • Some variability exists by block, though overall pressure remains light at this time
  • Freeze-damaged orchards may be more susceptible to colonization as stressed trees can favor psylla buildup

Regional Observations:

  • Gloucester County: None observed
  • Salem County: Newly emerged Adults observed
  • Burlington County: No activity observed to date
  • Mercer County: No activity observed to date

As orchards move through petal fall and temperatures warm, psylla populations may increase gradually, particularly in blocks where adults are present. However, given the widespread crop loss this season, economic risk is reduced in many orchards.

Management Considerations

  • In most blocks, immediate treatment is not necessary at this time
  • Continue monitoring for adults, eggs, and early nymphs, especially in historically infested blocks
  • Where management is needed, target newly hatched nymphs, which are the most susceptible stage
  • Focus treatments on blocks with high historical pressure, active populations, or significant freeze stress
  • Even with little to no crop, psylla should be managed where populations build to levels that may impact tree health, vigor, or lead to honeydew and sooty mold accumulation

Recommended Options

  • Movento (IRAC 23) – excellent systemic control of psylla, scale, and aphids (apply with a spreading/penetrating adjuvant for best performance)
  • Actara, Assail, Belay (IRAC 4A) – effective options for psylla control
  • Centaur (IRAC 16) – targets immature stages
  • Sivanto Prime (IRAC 4D) – effective, softer option with good activity
  • Agri-Mek (IRAC 6) – strong option when applied with oil/adjuvant, especially for nymph control

With little to no fruit in many blocks, psylla management should be highly targeted rather than routine. Focus on monitoring and only treat where populations threaten tree health or where there is a history of significant infestation.

Pear Diseases
Fire Blight and Early Season Management

As pear orchards move through petal fall and into early post-bloom, the primary bloom infection period is largely complete. However, fire blight remains a concern, particularly in blocks with freeze injury, where damaged tissue and rapid regrowth increase susceptibility.

The recent freeze has created additional risk for trauma blight, as injured blossoms and developing shoots provide entry points for infection during periods of warm temperatures, wind, or rain. At the same time, widespread crop loss reduces the need for fruit-focused disease programs, shifting management emphasis toward protecting tree health and controlling shoot blight.

At Petal Fall and Post-Bloom:

  • Continue monitoring forecasts using NEWA for fire blight risk, especially following storms or warm periods
  • Discontinue streptomycin after petal fall (not labeled beyond this stage)
  • Kasumin may be used up to petal fall only; do not apply afterward
  • Focus on protecting actively growing shoots, particularly during warm, wet, or stormy conditions
  • In high-risk situations, oxytetracycline (e.g., Mycoshield, FireLine) may be used post-bloom for shoot blight suppression

Management Considerations:

  • Monitor closely for trauma events (hail, wind, heavy rain), which can trigger shoot blight infections
  • Maintain heightened awareness in blocks with a history of fire blight or significant freeze injury
  • Rapid shoot growth under warm conditions increases susceptibility—vigorous orchards are at higher risk
  • With little to no crop in many blocks, focus management on tree health and reducing inoculum for future seasons

Fungicide Considerations (Post-Bloom)

  • Maintain protectant fungicides (e.g., Mancozeb, Ziram) for pear scab and Fabraea leaf spot to protect foliage
  • Use FRAC 3, 7, and premix fungicides (e.g., Inspire Super, Merivon, Luna products) where needed for foliar disease control
  • Rotate FRAC groups to manage resistance and maintain program efficacy
  • In blocks with little to no fruit, fungicide programs can often be reduced and focused on maintaining healthy foliage rather than fruit protection
Summary
  • The recent freeze has resulted in widespread blossom and fruit loss across many New Jersey pear orchards, with damage now more clearly defined at the block level.
  • Most orchards are now at petal fall to early post-bloom in southern counties, while northern counties have largely progressed through bloom with variable levels of injury.
  • Asian pear varieties, which were more advanced at the time of the freeze, experienced greater levels of injury in many locations; in most blocks, little to no viable fruit remains.
  • Pear psylla pressure remains low at this time; while populations may increase with warmer temperatures, most blocks do not require immediate treatment, though monitoring should continue—particularly in freeze-stressed or historically infested orchards.
  • Insecticide applications can be reduced in many blocks due to low crop; where needed, target early nymph stages and focus on blocks with active populations or a history of pressure.
  • Pear scab risk peaked during the April 25–27 infection period; current risk is declining, and one additional fungicide application is likely sufficient in most blocks to cover remaining primary infection.
  • Fire blight risk remains a concern in blocks with freeze injury and actively growing shoots; 1–2 additional bactericide applications may be warranted depending on conditions and model predictions.
  • With little to no crop in many orchards, management should shift toward maintaining healthy foliage, reducing inoculum, and supporting return bloom and productivity for the 2027 season.
  • Continued scouting and monitoring of weather conditions, pest activity, and tree response will remain important over the next 7–10 days.

Peaches
Peach Phenology

Peach and nectarine development continued to progress across New Jersey over the past week, and the impacts of the recent freeze event are now becoming more clearly defined. Significant injury to blossoms and young fruit has been confirmed in many orchards, particularly in southern counties.

Most varieties in southern New Jersey were at shuck split during the freeze, a highly sensitive stage, and have sustained substantial crop loss, especially in low-lying or frost-prone areas. In many blocks, little to no viable fruit remains, though isolated pockets of surviving fruit may still be present depending on site conditions.

In northern counties, where bloom was still ongoing at the time of the freeze, damage remains variable but is often still significant in more exposed locations. Some blocks may retain limited crop depending on bloom stage and site protection.

At this stage, surviving fruitlets are becoming easier to identify, although additional drop may still occur over the coming week. Growers should continue to assess crop viability at the block level before making final management decisions.

Despite reduced crop potential, maintaining disease management and overall tree health remains important to support return bloom and long-term productivity for the 2027 season.

Petal Fall / Early Cover Disease Programs

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 (e.g., ~2.5 lb/A)
  • Bacterial spot:
    • 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.
Insect Update

Insect management programs in peaches and nectarines should be adjusted this season based on 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)

  • OFM biofix has been set for April 7 in southern New Jersey and April 15 in northern counties
  • Degree-day accumulations should continue to be tracked from biofix to time first-generation management
  • In blocks with little to no fruit, OFM pressure will have limited economic impact; however, a well-timed application may still be beneficial to reduce populations, particularly in young blocks or orchards with historically high pressure
  • Where treatment is warranted, first-generation control should be timed around 170–200 DD (base 45°F) after biofix
  • A second treatment can be timed 10-14 days after petal fall where traps capture moths above threshold (>10) at 300-350 DD.
  • Mating disruption should remain in place where already deployed; do not remove dispensers
OFM 1st Generation Timing
  Insecticide Type
County/Region Degree Days

by 5/3 base 45

Conventional

170-200, 350-375

Diamide

100-150, 300-350

Gloucester – Southern 288 1st –past

2nd – 5/7-5/9

1st –past

2nd – 5/4-5/7

Middlesex – Northern 206 1st –4/30-5/2

2nd

 1st – past

2nd

Scale

  • Beneficial insects may help suppress populations in many blocks
  • In orchards with a history of infestation, plan to target the crawler stage later in the season
  • In severe infestations, materials such as Esteem or Centaur may be used
  • Where scale is a recurring problem, an application of Centaur at petal fall or Movento between petal fall and shuck split should “clean up” problem blocks. Centaur is recommended at 34.5 ozs./ac and Movento should be applied at 6-9 ozs./ac. A penetrant must be included to Movento as per the product label. Movento will also control green peach aphid when used at this time.
  • Continue monitoring historically infested blocks and planning for crawler management later in the season if populations persist.

Green Peach Aphid

  • Continue scouting as terminals expand and colonies begin to establish
  • Manage populations to prevent leaf curling and shoot distortion
  • Treatment thresholds remain:
    • Nectarines: 1 colony per tree
    • Peaches: 2–3 colonies per tree

Lesser and Greater Peach Tree Borers

  • Growers using mating disruption for borer control can begin placing dispensers around the end of April and 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 manage as usual in problem blocks

Other Insects

  • Plum curculio, tarnished plant bug, stink bugs, BMSB, Japanese beetle, TABM, and thrips: In most blocks with little to no fruit, treatment is not necessary

Recommended Options

  • OFM / Leafrollers:
    • Altacor, Asana, Delegate, Besiege, Voliam Flexi
  • Lesser and Greater Peach Tree Borers
    • Asana XL, Pounce 25WG
  • Green Peach Aphid:
    • Assail, Actara, Admire Pro
Summary
  • The recent freeze has resulted in widespread blossom and fruit loss across many peach and nectarine orchards, with damage now clearly defined at the block level
  • Most southern New Jersey orchards have little to no viable fruit remaining, while northern orchards show variable but often significant injury depending on bloom stage and site conditions
  • Surviving fruitlets are becoming easier to identify, though additional drop may still occur over the coming week
  • With minimal crop present, disease management programs can be significantly reduced, with emphasis shifting to maintaining foliage health and reducing inoculum for next season
  • Fruit diseases such as brown rot and rusty spot are not a concern in most blocks this season
  • Insect management programs can also be reduced; most fruit-feeding pests will not require treatment in blocks without crop
  • Oriental fruit moth should still be monitored and may warrant a well-timed application in high-pressure or young blocks to reduce populations
  • Green peach aphid and mites should be managed as needed to protect foliage and support return bloom
  • Maintaining tree health and canopy development remains critical to support productivity for the 2027 season
  • Continued scouting and monitoring of weather, pest activity, and tree response will be important over the next 7–10 days

Blueberries
Blueberry Phenology

Blueberries were observed in bloom throughout Atlantic and Burlington Counties. While the freeze event the week of April 20 had some impact on earlier blooming varieties, later-blooming acreage that did not have significant freeze damage is now hitting peak bloom (Draper, Elliott, etc.).

Insect Update

Scouting activities were conducted across 141 fields in Burlington and Atlantic Counties. Field evaluations focused on the presence of leafrollers, spongy moths, plum curculio, and thrips. There was a minor increase in plum curculio and thrips; however, due to the ongoing pollination period, the application of insecticides is not recommended at this stage.

IPM Data

Leafroller 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

 

Trap Monitoring: Cranberry and cherry fruitworm traps were deployed and will be monitored on a weekly. Scale traps targeting Putnam and terrapin scale will be set up in the coming week to monitor for first-generation crawler emergence and to assist in optimizing treatment timing.

Grapes
Grape Phenology

Grape development across New Jersey has progressed under recent warm conditions, with most vineyards in southern counties moving through early shoot growth stages. In many areas, shoots are now between 1–6 inches, 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 (Figure 2) 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 shoot viability and uniformity of growth. Blocks with uneven development may require adjustments in management timing over the coming weeks.

Grapevines with secondary bud break.

Figure 2. Grapevines with secondary bud break.

Diseases
Insect Update
  • Insect pests to monitor are grape flea beetle, and climbing cutworms. Controls for these insects are rarely needed.
  • The first generation flight of grape berry moth (GBM) was completed in April. Management of GBM will focus on controlling later generations when they migrate into fields after bloom.
  • Spotted lanternfly nymphs have been observed in southern NJ vineyards (Figure 3). There is no need to control SLF at this time.
    Spotted lanternfly nymphs on grapevines.

    Figure 3. Spotted lanternfly nymphs on grapevines.

    It’s also not too late to scout for and destroy SLF egg masses on posts and trunks.

Fire blight infection predicted week of April 13

NEWA is predicting a high risk for fire blight infection this week as a result of favorable conditions for apple orchards in bloom. Favorable conditions include 1) a certain number of heat units accumulated during bloom for a threshold level of inoculum to be reached; 2) a wetting event to wash the bacteria into infection sites; and 3) the average temperature is above 60°F. If at least two conditions are met during bloom, then the risk for infection is ‘High’ and antibiotics should be applied. A wetting event is not necessary to elevate the risk. Additionally, forecasted wetting events should be carefully considered and a bactericide applied just before or after a rain event.

When using the fire blight model on NEWA, it is important to enter your own “First Blossom Open Date” for your orchard as this can drastically change predictions. You can also enter your orchard’s history with fireblight in the first drop down menu. Lastly, you can enter the date you last applied an antibiotic this season and the model will reset to provide the most accurate predictions. When using the model, it is important to look at the column farthest to the right in the chart titled “Infection Potential EIP Value” since this is the most accurate prediction for our region. Any time the model shows an orange (High) or red (Extreme) output and the value for that date is above 100, an antibiotic application is warranted.

To manage fire blight in both apples and pears, consider using Kasumin at bloom. Kasumin is an antibiotic like Streptomycin and Oxytetratracycline. It contains Kasugamycin which is a different chemistry. Kasumin is only labeled for bloom and petal fall applications while strep and oxytet are labeled for post bloom use (note that Fireline 45 only allows for 1 postbloom application on apple). Using 3 different chemistries in rotation allows for resistance management while extending the protection into the post bloom period when late blossoms typically appear which ever material you use, the addition of Actigard or other plant defense elicitors may improve control. Applications of Apogee or Kudos during bloom can work to prevent shoot blight after petal fall. The use of Actigard and Apogee are especially recommended in new plantings where instances of shoot blight can kill young trees. For further recommendations on these products, Michigan State University published a guide including information on application timing and product rates.

Additionally, for peaches at petal fall, copper formulations should be used to suppress bacterial spot. Generally we recommend starting at 0.5 oz of metallic copper and gradually lowering the rate as the season progresses. The rate applied will depend on the formulation. Dr. Norm Lalancette published a chart listing common copper formulations and rates for peach and nectarine applications. Avoid combining copper with captan especially if it has been overcast for several days. Also avoid acidic spray solutions when applying copper. Dr. Lalancette has published a handy guide for copper applications in early covers. Antibiotics such as Mycoshield or Fireline may also be used and may offer slightly more residual activity during long wetting periods.

Caneberry Production Webinar April 8th – Registration Open

Registration is required. Click here to register: Webinar Registration – Zoom

New Jersey recertification credits will be awarded to registered individuals who confirm ID and license information.

1A – 3 Units, 10 – 3 Units, PP2 – 3 Units

Frost Protection for Orchards and Perennial Fruit Crops

The forecast for New Jersey statewide is expected to drop below freezing Tuesday and Wednesday overnight into early morning this week. Fruit crops are most vulnerable in the full bloom to petal fall stages.

Peach bud development stages and corresponding critical temperatures. Adapted from MSU Fruit Extension. Photos by H. Gohil.

Figure 1. Peach bud development stages and corresponding critical temperatures. Adapted from MSU Fruit Extension. Photos by H. Gohil.

Temperatures beginning at 28°F can kill 10% of the flowers when in full bloom and 90% of the flowers when temperatures drop to 24°F or below for more than 30 minutes (Figure 1). Please refer to your local forecast at nearby weather stations to receive the most accurate temperatures during this time period at www.njweather.org/ or https://newa.cornell.edu/.

Management Options for Frost Protection

  • Cloth coverings – This can be an effective tool to protect a small number of trees. Sheets, burlap, or frost blankets can provide some protection. Avoid plastic tarps which do not provide efficient insulation and can increase freeze damage on plant tissue. Ensure the covering reaches the ground.
  • Irrigation – Irrigate the soil under the trees the day before so any heat will be absorbed. Overhead irrigation is an option if available. The irrigation must stay on until ice starts to melt.
  • Heaters – Heat can be sourced through burning propane, natural gas, or oil burning Smudge pots. This could be a valuable investment for a commercial orchard that experiences frost events at critical bloom times; however, it is expensive and highly inefficient as heat produced dissipates quickly.
  • Wind machines & helicopters – These devices can be used in conjunction with heat or alone to mix warm air from higher elevation with cold air in the orchard.
  • Frost Rescue Sprays – Plant growth regulators such as Promalin can be applied to apples and pears following a frost event to help increase fruit set. The application must be made within 24 hours of the frost event and the trees must be thawed. Follow the label for use restrictions.

References

Gohil, H., Muehlabuer, M., Polanin, N, and Crassweller, R. (2020). Active Frost Protection Methods for Your Orchard. Rutgers Cooperative Extension Bulletin E363. https://njaes.rutgers.edu/e363/

Gohil, H., Muehlbauer, M., Besancon, T., and Ward, D. (2025). Preparing Orchards Against the Frost – Low Tech Strategies. Plant & Pest Advisory Rutgers Cooperative Extension Preparing Orchards Against the Frost – Low Tech Strategies — Plant & Pest Advisory

Demchak, K. (2020). Frost and Freeze Damage on Berry Crops. PennState Extension https://extension.psu.edu/frost-and-freeze-damage-on-berry-crops

 

 

Fruit IPM Updates Week of 3/23/26

Tree Fruit Phenology Update

Tree fruit phenology is progressing across New Jersey, with development in southern counties remaining slightly advanced and northern regions beginning to catch up. Overall, the 2026 season is showing a more compressed phenology window than typical. Cooler weather this weekend should help slow development.

In apples, green tip for Pink Lady was observed around March 22 across both southern and some northern regions, with Honeycrisp following around March 26. In pears, swollen buds were observed around March 11, with green clusters reaching by March 26 in southern New Jersey. Peach varieties in southern New Jersey were observed at the swollen bud stage this week.

Apples
Green Tip Dates by County
County Green Tip Date (earliest varieties) 
Cumberland 3/22
Gloucester 3/22
Burlington 3/22
Mercer 3/22
Middlesex 3/22
Monmouth 3/22
Hunterdon 3/22
Morris TBD
Warren TBD
Sussex TBD
Bergen TBD
Apple Scab
Models

Apple scab models are available through NEWA and RIMpro. Apply fungicides before infection events when discharge exceeds thresholds (10–20%).

Current Update
  • ~2% ascospore maturity (March 25)
  • ~7% by March 31
  • ~10% by April 1
  • Low cumulative discharge (~1–4%)
Management Considerations

Copper can be applied now but avoid after ½” green.

  • Manzate + single-site fungicide
  • DMI (FRAC 3) for high pressure
  • Vangard (FRAC 9)
  • FRAC 7 (save Aprovia)
  • Axios (save for later)
  • Syllit (avoid if resistance)
  • FRAC 11 (save for summer)
  • Topsin (limited uses)

As we move toward tight cluster:

  • Rapid ascospore increase
  • Higher infection risk with rain

Monitor:

  • NEWA models
  • Weather/wetting events
  • Phenology

Early control is critical to avoid season-long pressure.

Scouting Calendar

Use as a scouting guide only (not for spray timing).

  • Green tip: March 22–26
  • Ascospore maturity: 2–7% increasing
Key Points
  • Minimal difference between North and South Jersey
  • Green tip ~March 22
  • Prepare for scab infection events
  • Build fungicide rotation now

Pears
Pear Phenology Update

Pear phenology is progressing, with swollen buds observed around March 11 and green clusters observed on March 26 in southern New Jersey.

Pear Psylla

Pear psylla activity has begun in southern New Jersey, with variability across counties:

  • Salem County: adults and eggs observed
  • Gloucester County: eggs observed
  • Burlington County: no activity observed to date

These observations indicate that egg laying is underway in the southernmost regions and will likely progress north with warming temperatures. Reports from surrounding regions also suggest psylla activity is increasing.

At this stage:

  • Continue monitoring for eggs and early nymphs
  • Use beating trays to assess adult activity
  • Examine buds and developing shoots for egg presence

Dormant oil applications should be applied where possible to deter psylla egg laying and suppress early populations. Timely applications are especially important in areas where activity has already been observed.

At green cluster:

  • Oil is often combined with an insecticide to target migrating adults
  • In lieu of oil, particle films such as Surround may be used starting at swollen bud and continuing through bloom

Materials such as Esteem, Centaur, and Sivanto Prime may also be incorporated, depending on timing and pressure.

Adult pear psylla laying eggs.

Figure 1. Adult pear psylla laying eggs at swollen bud. Photo by Janine Spies.

Pear Diseases
Fire Blight and Early Season Management

Dormant copper applications should be applied for fire blight and pear scab suppression, but no later than green tip if fruit russet is a concern. Where copper has already been applied, early-season risk is likely reduced.

As bloom approaches:

  • Begin planning for antibiotic applications
  • Kasumin may be used at bloom and petal fall
  • Other options include streptomycin and oxytetracycline for post-bloom use

Rotating chemistries is important for resistance management.

Pear Scab

RIMpro modeling for pear scab in Upper Deerfield indicates low infection risk at this time, with infection values remaining below threshold levels. Despite recent wetting events, limited ascospore maturity is restricting infection potential.

Growers who have applied dormant copper are likely adequately protected under current conditions. Protective fungicide programs should begin at the cluster bud stage, particularly as we approach tighter cluster and bloom, when risk will increase.

Materials such as Ziram or EBDC formulations provide effective protection. At white bud, include materials effective against pear scab, rust diseases, and Fabraea leaf spot. Particular attention should be paid to rust on Asian pear varieties.

Dormant urea applications may also be used, where appropriate, to help reduce overwintering inoculum.

Summary
  • Pear psylla activity has begun in southern New Jersey, with adults and eggs observed in Salem County and eggs in Gloucester County
  • Dormant oil applications should be applied to suppress egg laying and early populations
  • Copper applications should be completed by green tip where russet is a concern
  • Pear scab risk is currently low based on RIMpro modeling
  • Fungicide programs for pear scab should begin at cluster bud as risk increases
  • Dormant urea may be used to reduce overwintering inoculum

Continued scouting will be important over the next 1–2 weeks as both insect and disease pressure increase with advancing phenology.

Peaches

Peach Phenology

Peach varieties in southern New Jersey were observed at the swollen bud stage this week. Development is progressing steadily and will advance with warming temperatures.

Peach Swollen Bud

Figure 2. Peach Swollen Bud. Photo by Janine Spies.

Brown Rot

Blossom infections from the brown rot fungus can occur whenever pistils are exposed and favorable environmental conditions are present.

Infections can occur during any wetting period when temperatures are between 41 and 86°F. Optimum conditions occur with wetting and temperatures in the mid-70s. During extended wetting periods (several days or more), blossoms can be infected regardless of temperature. Infections under suboptimal conditions are generally less severe.

Blossoms and fruitlets remain susceptible until the pistil desiccates, which occurs sometime between petal fall and shuck split.

Initiate coverage for blossom blight starting at pink for short-petaled varieties and at 5–10% bloom for showy flowers. Refer to the NJ Commercial Tree Fruit Production Guide for recommended materials and rates.

Scale Insects

Oil applications may be safely applied up to pink on peach.

Oil can be applied alone or in combination with insecticides including Centaur, Sivanto Prime, and Esteem.

SOUTH JERSEY CALIBRATION GROWERS MEETING

March 25, 2026
2:30 pm – 6:00 pm
Rutgers Agricultural Research & Extension Center
121 Northville Road
Bridgeton, NJ

Program

Program Chair
Janine Spies, Rutgers Cooperative Extension
Statewide Program Leader in Fruit IPM

2:30 – Registration

3:00 – Welcome and Introductions

3:15 – Airblast Sprayer Calibration Techniques
Chris Lovenduski, Central Jersey Equipment

4:15 – Early season management in peaches
Anne Nielsen PhD, Professor & Extension Specialist in Entomology

4:45 – Light fare & refreshments (Pre-registration required)

5:00 – Coverage Counts: How to make the most of a pesticide application
Karly Regan PhD, Certis Biologicals

5:30 – Pesticide Safety and Regulations for Specialty Crops
Janine Spies PhD, Rutgers Cooperative Extension

6:00 – Pesticide Recertification Credits and Adjourn. Attendees must be present for the entire program in order to apply for NJDEP credits.

THE FOLLOWING NJDEP PESTICIDE RECERTIFICATION CREDITS WILL BE AWARDED

4 CAT-10     4 CAT-1A     3 CAT-3A     4 CORE     4 PP2

Click here to register: South Jersey Calibration Event Registration – Fill out form

PRE-REGISTRATION BY March 18, 2026

Registration cost per person is $10. Cash or check (made payable to Rutgers The State University) will be collected at the door.

If you have any questions please contact Janine Spies: (352)-231-6330, janine.spies@rutgers.edu