Tree Fruit Edition

Seasonal updates on insects, diseases, weeds, maturity dates and cultural practices impacting only tree fruit.
 
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August 5, 2020

Fruit IPM for 8/4/2020

Grapes:

Spotted Wing Drosophila (SWD): The spotted wing drosophila is an invasive fruit fly which can infest sound ripe thin-skinned fruit. The SWD female has a saw-like ovipositor which she uses to literally saw through healthy skin and deposit her eggs, which develop into small maggots. At this time of year each generation takes slightly over 1 week to complete. Each female can lay about 300 eggs over her lifetime, and given the time of year it is, we will probably see 3-5 more generations by the time grapes are harvested. Over the past several years we have monitored SWD in vineyards during August through September. A well-known link exists between high populations of native fruit flies and the prevalence of late season sour rot in grapes. What we don’t know is how the prevalence of SWD might be able to aggravate or help increase the late season populations of native fruit flies, or if the total fruit fly complex (native and invasives) is higher because of the presence of SWD. [Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape
August 3, 2020

The 2020 Hurricane Season: A Phytophthora Epidemic on Tree Fruit?

You’ve probably heard it by now. The National Oceanic and Atmospheric Administration (NOAA) predicts an above-normal Atlantic hurricane season for 2020. NOAA predicts “a 60% chance of an above-normal season, a 30% chance of a near-normal season and only a 10% chance of a below-normal season.” This translates to 6-10 hurricanes (>= 74 mph winds), including 3-6 major hurricanes with winds of 111 mph or greater.

What does this forecast have to do with tree fruit production? These high winds may cause tree fruit roots to crack and split.  Wounds created by this activity allows for entrance of the Phytophthora root rot pathogen. Flooding also facilitates movement of pathogen spores through the soil. Once infected, cankers and root rot develop during subsequent months, leading to tree death this fall or next spring and summer.

Although Isaias is only a tropical storm, winds may get high enough to cause some damage to anchoring roots.  Nevertheless, we still have four more months of the Atlantic hurricane season remaining, which runs from June 1 through November 30. Given the potential for loss and the above normal risk for hurricane development, it is probably prudent to review some basic information on disease development and control.

Peach and apple trees at 3 to 5 years of age are most susceptible to wind injury and subsequent infection by Phytophthora species. If trees are leaning to one side, or there is open space around the collar, this is a good indication of “tree whipping” and therefore root injury. Younger trees tend to be more flexible and therefore less likely to be damaged, especially when the soil is softened by excessive rainfall. Older trees with large, well-developed root systems are more likely to fend off the wind; limb breakage and fruit loss may be a bigger concern on these trees. Of course, wind speed plays an important role in the severity of damage across all age groups.

If injury is thought to have occurred, fungicide application should be considered immediately after the storm subsides to limit Phytophthora root and crown rot development. Ridomil Gold, applied to the soil, is the recommended fungicide. Foliar applications of a phosphorous acid material, such as Aliette, Agri-Fos, Phostrol, etc… are alternative controls.  If damage is severe across all age groups, one approach would be to apply Ridomil to 3-5 year old trees and a phosphorous material to young and old trees.

If time and weather permits, application of root or foliar fungicide prior to the hurricane may help “immunize” the trees before infection can occur. Both types of fungicides are highly systemic. However, one needs to allow time for the Ridomil to move through the soil and be absorbed by the roots. Excessive storm flooding could wash away the fungicide before it has a chance for root absorption.  Of course, once these materials are applied, the hurricane will most likely change course! Hence, the disadvantage of applying before the storm.

For details on application and rates of Ridomil Gold and Aliette, see the NJ Tree Fruit Production Guide (2016 issue) and product labels.

Filed Under: Tree Fruit
August 2, 2020

Statewide Wine Grape Twilight – II (Webex)

Please follow the the link below the program agenda, to attend the Wine Grape Twilight – II meeting, scheduled on August 5 (Wed), 6 pm – 7:30 pm. There is no registration requirement for this meeting.

Growers Questions and Discussions:

  • My vineyard could be developing resistance to Downy Mildew (DM) spray. What should I do as far as the spray program?
  • Can change to complete cane pruning from spur pruning, help in reducing the resistance to DM?
  • Phenology based spray or weather-based spray is more effective, during the early growth?
  • Does high catch-wire canopy result in poor spray penetration into the fruit zone?
  • How to convert leaf petiole test results into fertilizer recommendation?
  • Guidance on getting Ready for the fall pre-emergent herbicide application?
  • Is there anyone in NJ that is collecting grape grower data on Spotted Lantern Fly appearance and pressure?

[Read more…]

Filed Under: Blueberry, Cranberry, Fruit, Strawberry, Tree Fruit, Wine Grape Tagged With: , , ,
July 28, 2020

Fruit IPM for 7/29/20

Peach:

Stink Bugs Apples and Peaches: Brown Marmorated Stink Bug (BMSB) has been steadily increasing in isolated locations. The highest levels seen are on 2 farms in Gloucester County at 4 per trap and at 2 farms in Morris County at 16 and 18 per trap. The Morris County traps are adjacent to apples, and represent high levels of BMSB. Most, but not all of the pyrethroid  and pyrethroid premixes have good activity for BMSB. See the 2020 NJ Tree Fruit Production Guide for a list of effective materials. Where growers are using OFM mating disruption in peaches, then weekly border sprays for BMSB will help. In apples a 7 day program may be needed as trap captures increase. [Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape
July 21, 2020

Fruit IPM for 7/22/20

Peach:

Stink Bugs Apples and Peaches: Brown Marmorated Stink Bug (BMSB) increasing in spotty locations. BMSB has many alternate hosts, and orchard populations always seem to be ‘local’. In some cases BMSB counts are up to 7-10 per trap in Gloucester County and 19 per trap in Morris County. Most of our traps in northern counties have been placed near apples, and these types of populations can be very problematic.  Most, but not all of the pyrethroid  and pyrethroid premixes have good activity for BMSB. See the 2020 NJ Tree Fruit Production Guide for a list of effective materials. Where growers are using OFM mating disruption in peaches, then weekly border sprays for BMSB will help. In apples a 7 day program may be needed as trap captures increase.

Oriental Fruit Moth (OFM): We are at the treatment timing for the third generation, but populations are so low that most growers can either stretch their insecticide timings or target other pests such as BMSB if stinkbugs are present.

OFM 3rd Generation Degree Day (DD) Timing
      Insecticide Type
County/Region Biofix DD by 7/21 base 45 Conventional

2100-2200, 2450-2500

 Diamide

2025-2150, 2375-2450
Gloucester –Southern 4/3 2207 1st – 7/19-21

2nd – 7/30-8/1

 1st – 7/17-19

2nd – 7/28-30
Hunterdon – Northern 4/9 1896 1st – 7/27-30

2nd – too far out

 1st – 7/25-27

2nd – too far out

 

Apple:

Spotted Lanternfly (SLF): SLF nymphs are present in several orchards in northern Hunterdon and Warren Counties, but not yet seen directly on the trees; rather in sticky traps placed for BMSB. There are no treatment thresholds for either nymphs or adults on peaches or apples. Any insecticides used for BMSB should also kill SLF nymphs and adults, although it is unknown at this point, if these are going to be problematic in apples. High populations of adults just prior to harvest, may secrete enough honeydew to cause a sooty mold on fair to light skinned varieties.

Codling Moth (CM): Trap captures are very low statewide. However, control of the first generation has been problematic, with infested fruit present in a number of orchards. Growers should pay close attention to their CM trap captures. When male moths start to be captured, and especially when over 5 moths per trap, then insecticides need to be applied.  We expect to see the second generation flight very soon.

Rots : Various rots, mostly bitter rot are appearing in a number of orchards. Special attention should be given to susceptible varieties like Honeycrisp and Empire where bitterroot has been a problem in previous years. Bitter rot infections will continue during wetting periods for the rest of the summer.  The QoIl premixes Merivon and Pristine are good rot materials with Merivon being the better of the two. Luna Sensation and Luna Tranquility are also rated as effective. Alternate with a Captan/Prophyt mix or Captan/Topsin. Topsin has some efficacy for white and black rots but is not effective against bitter rot.

Grapes:

Disease control has been very good so far in the vineyards we are scouting. We have seen some sunburn which can be confused with diseases. Low levels of downy mildew have been noted. In vineyards with Phomopsis present on leaves some fruit rot is appearing. Fruit symptoms are hard brown berries that eventually develop black fruiting bodies on the skin.

Grape Berry Moth: The next timing for GBM will be on or about 7/28 if using Altacor or Intrepid in southern counties. Growers using other insecticides can wait a few days longer.

Scouting Calendar Tree Fruit Southern Counties

The following table is intended as an aid for orchard scouting. It should not be used to time pesticide applications. Median dates for pest events and crop phenology are displayed. These dates are compiled from observations made since 1995 in Gloucester County. Events in northern New Jersey should occur 7-10 days later.

 

Pest Event or Growth Stage Approximate Date 2020 Observed Date
Bud Swell (Redhaven) March 23 +/- 15 Days March 9
1/4″ Green Tip Red Delicious March 31 +/- 13 Days March 18
Pink Peach (Redhaven) April 4 +/- 15 Days March 18
Tight Cluster Red Delicious April 9 +/- 13 Days March 29
Oriental Fruit Moth Biofix April 9 +/- 13 Days April 3
Full Bloom Peach (Redhaven) April 9 +/- 14 Days March 29
Pink Apple (Red Delicious) April 14 +/- 12 Days March 12
Codling Moth Biofix April 27 +/- 13 Days May 4
Full Bloom Apple (Red Delicious) April 22 +/- 11 Days April 25
Petal Fall (Redhaven) April 22 +/- 10 Days April 14
Petal Fall (Red Delicious) April 27 +/- 14 Days May 4
Shuck Split (Redhaven) April 30+/- 11 Days May 1
Tufted Apple Bud Moth Biofix May 4 +/- 10 Days May 6
Pit Hardening Peach June 16 +/- 8 Days June 16

 

Tree  Fruit Trap Counts – Southern Counties

Week ending STLM TABM-A CM BMSB OFM-A DWB OFM-P TABM-P LPTB PTB
4/11 1       7   0      
4/18 0 0 0   36   2      
4/25 1 0 0   12   0 0    
5/2 1 0 0   24   1 0 0  
5/9 2 1 0   26   2 1 12  
5/16 7 4 0   0 0 1 0 2  
5/23 2 5 1   1 0 0 6 3  
5/30 0 3 0   0 3 0 4 3  
6/6 2 7 0   0 14 0 9 13  
6/13 0 5 0   0 12 0 6 2 0
6/20 0 3 0   0 12 0 2 0 0
6/27 1 0 0   0 1 0 0 1 2
7/4 1 0 0   0 1 0 0 0 2
7/11 0 0 0 1 0 0 0 0 0 0
7/18 0 0 0 2 0 2 0 0 0 1

 

Tree  Fruit Trap Counts – Northern Counties

Weekending STLM TABM-A CM BMSB OFM-A DWB OBLR OFM-P TABM-P LPTB PTB
4/11         0     0.7      
4/18 0   0   0.5     1.0      
4/25 2   0   0.7     0.7      
5/2 5   0   1.8     1.2      
5/9 5 0.2 0.3   36.7     10.1 0    
5/16 17 0.2 0.4   19.2 0   2.7 1 1.8 0
5/23 18 5.7 2.1   36 1   6.3 10.3 1.5 0
5/30 5 7.2 1.9   57 1   2.6 6.7 9.1 0
6/6 4 15.8 4.1   25.8 0   4.6 18 13 0.3
6/13 15 17.4 4.3   8 1.3 9.5 3.4 20.6 21.8 0
6/20 16 33.8 4.8   9.8 0 9 1.2 34.1 8.3 0
6/27 20 10.9 1.6 1.2 9.8 0.2 0.5 1.5 12.7 5.8 0.3
7/4 18 5.8 0.7 2.5 9.4 0 0 1.5 9.3 3.8 2.5
7/11 14 1.7 0.3 1.9 14.3 0 0 2.4 4.3 5.1 1.5
7/18 11 0.5 1.5 2.0 3.4 0.5 1 2.5 1.5 1.4 3.8

 

Blueberry:

Tailing Down…But Spotted Wing Drosophila (SWD) is still the main pest of concern. Bluecrop is being machine picked and Elliott has started full swing. Late season varieties still must be protected since SWD continues to build higher populations.

Aphids: Aphid populations have decreased to an average of 2.5% of terminals infested with a high of 25% last week. However with the heat wave, actual numbers as of this writing are even less.  While we originally thought we might need some post-harvest applications to control this pest, the recent heat is cooking them in the fields. The combination of aphids not being able to take the heat, and the plant tissue starting to harden off will take care of this pest for the remainder of the season.

Putnam Scale: Scale infested fruit is very low at .02% infested fruit. Growers who have had any of this first generation damage should be prepared to treat those fields when second generation crawlers become active in 2-3 weeks.

By the Numbers:

% Injured Fruit
Week Ending % LEPS Injured Fruit % PC Injury Fruit % Scale % CBFW
  Avg Max Avg Max Avg Max Avg Max
5/11 0.05 0.1 0.2 0.3        
5/18 0.06 0.8 0.13 1.4        
5/25 0.122 1.1 0.43 3.8        
5/30 0.17 1.4 0.70 5.6        
6/6 0.122 1.1 0.43 3.8        
6/13 0.01 0.4 0.001 0.4 0.005 0.1    
6/19 0.003 0.2 0 0 0.02 0.5    
6/27 0.001 0.3 0.001 0.2 0.03 0.6 0.005 0.1
7/4 0.0 0.0 0.0 0.0 0.03 0.5 0.0005 0.1
7/11 0.005 0.1 0.0 0.0 0.02 0.5 0.0 0.0
7/18 0 0 0 0 0.02 0.4 0 0

 

Trap Counts
Week Ending CBFW-

AC

 CBFW-BC SWD-

AC

 SWD-

BC

 OB-BC OB-AC
  Avg Max Avg Max Avg Max Avg Max Avg Max Avg Max
5/11 0.1 1 0 0                
5/18 0 0 0 0                
5/25 0.1 1 0.25 1 0.8 7 0 0        
5/30 0 0 0.25 1 .75 5 .55 1        
6/6 5.5 34 0.75 3 2 8 2.1 5        
6/13 5.6 22 3.5 8 4 14 7.7 20 3.2 11 18 340
6/19 7.2 48 6.5 18 4.64 30 4.9 16 71.75 675 21.4 68
6/27 0 0 3.5 8 2.8 12 4.3 25 1834 13750 462 2025
7/4 0.22 1 1 3 4.17 16 11.3 46 2421 8775 976 5062
7/11 0.11 1 0.25 1 5.8 27 6.6 22 1093 5000 1997 6075
7/18 0.11 1 0.5 2 5.3 19 4.6 14 769 5000 1575 6750
 
Week Ending SNLH – AC SNLH-BC BBM-AC BBM-BC    
  Avg Max Avg Max Avg Max Avg Max Avg Max Avg Max
6/27 0.14 3 0.8 4 0 0 0 0        
7/4 0.08 1 0.8 5 0.009 1 0 0        
7/11 0.12 1 1.82 6 0 0 0 0        
7/18 0.11 2 1.16 5 0 0 0 0        
Key: PC=plum curculio, Scale=Putnam scale, CBFW=cranberry fruitworm, SWD=spotted wing drosophila, OB=oriental beetle, SNLH-sharpnosed leafhopper, BBM=blueberry maggot, BC=Burlington County, AC=Atlantic County
Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape
July 21, 2020

Don’t Let Your Guard Down With Farm Worker Health

The COVID-19 pandemic has highlighted the critical, indeed essential, role of farm labor in getting food from farm to plate. However, health concerns should not stop with a negative COVID test, especially if an employee or family member is exhibiting any of the ‘flu-like’ symptoms that are associated with corona virus.

A recent farm call was a reminder that working outside, especially during this July heat wave, exposes workers to a number of potential health risks that may present very similar symptoms and can be equally health, and even life, threatening. Recently published studies from the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences suggest growing numbers of people worldwide are at risk of heat stress and related complications, including farmers and ag laborers working in high heat and humid conditions.

Harvesting and other activities along field edges, including going into the woods instead of using a portable bathroom facilities, also lead to a high risk of tick bites, which can also carry a number of diseases, many as or more debilitating than Lyme disease that most are now aware of. A recent story at Today.com suggested that the COVID-19 pandemic might lead to more tick-borne disease this year, quoting Rutgers entomologist and assistant professor Alvaro Toledo at the Center for Vector Biology with suggestions how to prevent tick bites.

It is critical for your employees’ health and well-being to get proper diagnosis and treatment for all of these ailments. This table illustrates how many tick-born diseases, as well as heat stress, all have potential symptoms very similar to those of COVID-19. Each is linked to additional resources at the CDC. In many cases, it may be the ‘other symptoms’ that may be unique to each disease and assist a medical practitioner with correct identification and lead to better verification with further testing.

   Disease    >

Symptoms  v

 COVID-19 Heat Stress Lyme Disease Ehrlichiosis Babe- biosis Powas-san Rocky Mtn Spotted Fever
Vector* Human Black-legged Tick (a.k.a. Deer Tick) (I. scapularis) Lone Star Tick (A. americanum) & Black-legged Black-legged Tick Ground hog(I. cookei), Squirrel (I. marxi) & Black-legged Ticks American Dog Tick (D. variabilis)
Fever or chills X X X X X X X
Cough X X
Shortness of breath/difficulty breathing X
Fatigue X X X X
Muscle/body aches X X X X X X
Headache X X X X X X X
New loss of taste or smell X
Sore throat X
Congestion or runny nose X
Nausea/vomiting X X X X X X X
Diarrhea X X
Rash X X X
Other symptoms X X X X X X
Potentially Deadly/Disabling
 X X X X X X X

*NOTE – main vector listed, but many tick born diseases may be vectored by other species of ticks, or different species causing same disease may be carried by different tick species.

Filed Under: Blueberry, Commercial Ag Updates, Cranberry, Field, Forage & Livestock, Fruit, Landscape, Nursery, & Turf, Nursery, Strawberry, Tree Fruit, Turf, Vegetable Crops, Wine Grape Tagged With: , , , , , , ,