Archives for June 2024

Additional Information for New Jersey Farm Owners on H5N1 Bird Flu

The New Jersey Departments of Health (NJDOH) and Agriculture (NJDA) are closely monitoring the emerging situation with H5N1 bird flu and would like to provide important information to New Jersey farm owners. Please refer to the memo from NJDOH and NJDA: Information for Farm Owners and Farm Workers (highlights provided below). The public health risk of H5N1 bird flu is low, but people can sometimes get bird flu, usually after close, unprotected contact with infected animals. Poultry and livestock farmers and workers, veterinarians and veterinary staff, and slaughterhouse workers performing certain tasks on lactating dairy cattle are at increased risk of exposure to animals infected with bird flu viruses. Farms containing multiple species, particularly cattle, and/or poultry, should uphold biosecurity practices that reduce the risk of disease spreading between animals. Farm staff and visitors should adhere to recommended precautions regarding contact with other animals and follow personal protective equipment (PPE) protocols.

Rutgers Cooperative Extension is collaborating with NJDOH, following guidance from the CDC, to assist farm owners with preparedness by providing initial PPE supplies by request at county extension offices. To request PPE supplies and/or receive additional information, please contact your respective county extension office (https://njaes.rutgers.edu/county/). You will be asked to specify the quantity and type of PPE needed for your operation.

Refer to the Centers for Disease Control and Prevention’s flyer “Protect Yourself from H5N1 When Working With Farm Animals,” for more guidance on the application, removal, and disposal (or possible re-use) of each personal protective equipment item.

PPE from NJDOH includes the following as supply remains available:

  • Bouffant caps
  • Coveralls
  • Face shields and refills
  • Goggles
  • Gloves
  • N95 respirators
  • Gowns
  • Shoe covers

Identifying and controlling leaf mold in high tunnel & greenhouse tomato production

Leaf mold occasionally appears in high tunnel or greenhouse tomato production in New Jersey. However, under ideal conditions the disease will develop in field-grown crops. The fungus will cause infection under prolonged periods leaf wetness and when relative humidity remains above 85%. If relative humidity is below 85% the disease will not occur. Therefore, the proper venting of high tunnels and greenhouses on a regular basis is important. The pathogen can survive (overwinter) as a saprophyte on crop debris or as sclerotia in the soil. Conidia (spores) of the fungus can also survive up to one year in the soil.

Symptoms of leaf mold on infected tomato plant. Note the bright yellow leaves and the olive-green spores developing on the undersides of leaves.

Symptoms of leaf mold on infected tomato plant. Note bright yellow leaves and olive-green spores developing on undersides of leaves.

[Read more…]

Vegetable IPM Update 6/12/24

Sweet Corn

European corn borer (ECB) moths continue to be captured in blacklight traps in the northern and central counties, with highest moth activity in Middlesex, Somerset and lower Hunterdon counties.  The highest feeding levels are in Somerset and southern Hunterdon Counties.   ECB injury over 20% of plants infested has been found in that area recently.  While ECB has become something of a local phenomenon in NJ, growers should not assume that feeding is below economic levels in their area.   It is typical for feeding percentages to rise as the moth catch declines.  We expect feeding to increase for the next 1-2 weeks before peaking.

Look for the characteristic “shot-hole” type of feeding (photo  below at right) and consider treating when infested plants exceed 12% in a 50 plant sample.  As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels (see photo at left)It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time.  This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.

 

Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen or Vantacor (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen.  Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn.  Control with these materials is very inconsistent.

The highest nightly trap catches of ECB for the week ending 6/12/24 are as follows:

Bellemeade   3 Denville   1 Milford   1
South Branch   2 Georgetown   1 Oldwick   1
Asbury   1 Hillsborough   1 Pennington   1
Dayton   1 Lawrenceville   1 Sergeantsville   1

[Read more…]

Insect Pest Management During Bloom – June 12, 2024

Cranberries have started to bloom, and bees are active in bogs. If insects have been effectively managed prior to bloom, we recommend no sprays at this time. A reminder: when bees are present, your choices of insecticides are insect growth regulators (IGRs) such as Intrepid 2F or Bt products such as DiPel.

During bloom, we recommend monitoring insect populations using pheromone traps. Pheromone traps should be used particularly to monitor the activity of Sparganothis fruitworm and blackheaded fireworm, two key pests in New Jersey.

Degree-Day Model for Sparganothis Fruitworm

Sparganothis fruitworm adults

Together with Dr. James Shope, Assistant Extension Specialist in the Department of Environmental Sciences at Rutgers University, we have been working on refining a degree-day model for Sparganothis fruitworm using trapping data from New Jersey. According to this model, 25% flight activity should occur at 840 degree-days, and peak flight activity at 952 degree-days (starting on April 15). As of today, Sparganothis fruitworm has accumulated 724 degree-days, indicating that flight should have started but has not yet reached 25%. Note that this model includes data from many bogs and varieties, which may behave differently from the overall model. Therefore, it is advised to monitor closely as the expected peak flight approaches.

Controlling basil downy mildew in the greenhouse

Basil downy mildew (BDM) can cause significant losses in the greenhouse. Once introduced into the greenhouse it can be very difficult to manage and eliminate. In the past few years, a vast amount of research has been done on understanding BDM biology and controlling it in the greenhouse using different cultural practices. Before we get to control strategies, let’s review what we know about the pathogen.

First, basil downy mildew is an obligate parasite – meaning it needs a living host to survive. As long as basil is in production in the greenhouse there will be a potential source of inoculum. Sources of inoculum can include fresh intact leaves, but also leaves discarded and fallen on the floor or in an open garbage container. This is important for greenhouse growers who produce basil year round or growers who are looking to extend basil production to later into the fall or earlier in the spring. The simplest method to break the disease cycle would be to stop growing basil for a short period of time and keeping your greenhouse as clean as possible. This would help break the disease cycle by removing the host. Sporangia produced by BDM are short-lived. Without a host their survival is only a few hours to a few days depending on the temperature and environmental conditions. The latent period (the time between infection and symptom development) can range from 5 to 10 days depending on the temperature and environmental conditions. This informs us that plants which appear uninfected may actually be infected without symptom development. Therefore, it is critically important to remove all plants from the operation before restarting production (especially if BDM is already present). A good time to stop greenhouse production (i.e., in the mid-Atlantic region or more northern regions) would be after the first hard freeze in the fall – after the freeze kills all potential sources of inoculum that could come from sources outside the greenhouse.

Control strategies using cultural practices in the greenhouse

Reducing relative humidity in the greenhouse

Basil downy mildew requires high relative humidity (>95%) for 7.5 hrs and at least 4 hrs of leaf wetness for sporulation. Sporulation has been shown to be significantly reduced, or not capable when relative humidity is less than 85%. Thus, maintaining relative humidity below 85% in the greenhouse can significantly help reduce spore production. If this is not possible interrupting the dew cycle (i.e., leaf wetness) with 10 minute periods of drying via fanning/venting every 2 to 4 hours can help reduce spore production.

Control using light

Research has shown that infected plants kept under 24 hours of continual light are unable to sporulate, this was also shown to be temperature-dependent. The type of lighting is also important. Incandescent light was fully inhibitory at 15 to 25oC, but not 10oC. Narrow band LED illumination with red light has been shown to be more inhibitory than blue light. Thus, lighting basil during the night every few hours at short periods of 10 minutes can help reduce sporulation.

Control using fanning and ventilation

Continuous fanning during the night has been shown to dramatically reduce BDM development by reducing leaf wetness (i.e., dew) and reducing relative humidity (keeping it below 95%). Recommendations from Israel are to initiate fanning when relative humidity reaches 70% in the greenhouse and to stop it when it is below 60%.

The key to controlling and mitigating BDM development in the greenhouse is controlling relative humidity and periods of leaf wetness to help reduce potential sporulation. Using a combination of cultural practices mentioned above can help reduce BDM development, but it will come at a cost to you in the form of additional hardware, temperature and relative humidity monitoring equipment and the cost of electricity. The first step in this process involves understanding where the initial source of inoculum may be coming from. Evidence for BDM being seed-borne is mixed. During the spring-summer-fall, greenhouse basil production will always be at-risk from infections coming from an outside source, including diseased seedlings you may be purchasing. Successfully breaking the BDM disease cycle (without the use of chemical inputs) in greenhouse operations has limited opportunities (e.g., in northern regions where freezing weather occurs). This can only occur in the fall, after freezing weather which can kill all outside sources of inoculum and by not carrying over infected plant material into the winter season, thus the need for a basil-free period during the production cycle. This is especially important in small greenhouse operations that produce basil organically or without the use of chemical input.

These management practices should significantly reduce your BDM problems though will require more of your attention and potentially additional equipment and supplies. Coupling best management practices with new downy mildew resistant basil varieties will further provide protection to you. Try the new basil downy mildew resistant varieties including Rutgers Obsession DMR, Rutgers Devotion DMR, Rutgers Passion DMR, and Rutgers Thunderstruck DMR or other DMR resistant sweet basils such as Prospera, and see which ones work best for you.

For information on Rutgers DMR sweet basils, where to purchase seed, as well as control strategies, and ongoing research efforts please follow the Rutgers basil downy mildew breeding program on Instagram at #Rutgersbasil.

Resources:

Tracking basil downy mildew in the US

Managing basil downy mildew

Fungicides for the control of BDM

Controlling basil downy mildew in the greenhouse

Authors: Andy Wyenandt and Jim Simon, Department of Plant Biology, Rutgers University

 

Tree Fruit IPM Report June 12, 2024

Peach:

Bacterial Spot: Fruit symptoms have begun to appear in southern counties. So far fruit symptoms are very low and only in highly susceptible varieties. Peaches are at or past pit hardening and fruit now has some resistance to bacterial spot. Infections can still occur but will be less unsightly and may still make grade. Growers should continue to manage using Oxytetracyclene and lower rates of copper, especially around rainy periods and severe weather.

Oriental Fruit Moth: A biofix point for OFM was set on 4/10 in both northern and southern counties.  All Treatments for the first generation have past.

OFM 2nd Generation Timing
Insecticide Type
County/Region Degree Days by  6/11base 45 Conventional

1150-1200

1450-1500

Intrepid/Rimon

1050-1150

1300-1400

Diamides/Virus

1075-1150

1375-1450

Gloucester – Southern 1163 1st –June 11-13

2nd – June 20-23

1st –June 7-10

2nd – June 16-19

1st –June 8-10

2nd – June18-21

Middlesex – Northern 1033 1st – June 15-17

2nd – too far off

1st – June 12-16

2nd – too far off

1st – June 13-16

2nd – too far off

Tarnished Plant Bugs; and Other Catfacing Insects: Catfacing insects are active, and activity is increasing with dry weather and summer temperatures. Very little recent fruit feeding has been observed.

Scale Insects: White peach scale crawlers began emergence around mid-May in southern counties and San jose scale crawlers began emergence around May 25 and will continue emergence for up to 6 weeks. Control options during crawler emergence include Neonicitiniods (suppression only), Sivanto, and the IGR’s Esteem and Centaur. Refer to the NJ Commercial Tree Fruit Production Guide for more information.

Thrips: If the current dry spell continues Flower Thrips may become an issue in highly colored ripening fruit, especially in poorly managed ground covers that contain clover or other flowering weeds. Thrips damage appears as “silvering” and usually appears on fruit close to harvest. If populations are high damage can be extensive. Presence of thrips may be scouted for using a beating tray to detect the presence of adults and nymphs in the tree. Flowering weeeds and shrubs on orchard edges may also be scouted by shaking flowers onto a beating tray or a sheet of paper. Delegate or Entrust at the highest labeled rate are the usual recommended materials for thrips in stone fruit. Lannate may be effective in some orchards but has not worked well in recent years. These materials all have short PHI’s and may be applied close to harvest when damage typically appears. Thrips have also been observed to mark cherries. Damage is different than peach and appears as a dark streak in a similar pattern as silvering. Refer to the NJ Commercial Tree Fruit Production Guide for more information.

 

Apples and Pears:

Diseases: Now that primary scab is nearing the end, or has ended, the focus turns toward summer diseases such as fruit rots (esp. Bitter rot), and sooty blotch and fly speck. Bitter rot control has been difficult at best in recent years even where management programs have been rigorous. Research has suggested Products such as Merivon, Luna Sensation, Inspire Super, and Aprovia may be effective, and longtime reliable broad spectrum fungicides such as omega, captan and ziram should provide control. Experience has suggested that the addition of phosphorous acid products such as Prophyt or Rampart to captan sprays may improve control. Observations are that these products improve control of other summer diseases such as sooty blotch and flyspeck, and may help suppress scab infections where present.

Fire Blight: Fire Blight symptoms began appearing in southern county apple and pear orchards the week of 5/20, and in northern counties the week of 5/13. Typically it is recommended to cut out infected limbs however this is a practical decision that must be made. This blog post from Michigan State may be helpful to decide whether it is worth cutting out infected tissue. Once the terminal buds set, typically in July, infected wood should be removed to prevent colonization by the bitter rot pathogen.

Codling Moth (CM): The first generation codling moth timings have ended. Trap captures Continue and increased in some southern county orchards this week. A biofix was set for CM on April 17th in both northern and southern counties. Second generation timings are updated below. Rimon is not recommended for this and later generations.

Codling Moth Degree Day Timing – Second Generation
Application and Insecticide Type
County Area Biofix 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 22 Too far off Too far off Too far off Too far off Too far off
Northern  May 1 Too far off Too far off Too far off Too far off Too far off

Ambrosia Beetle : Infested trees are showing signs of stress. If you have had a history of this pest in your orchard, now is a good time remove and burn any trees that have been attacked as the flight appears to be declining or is over.

Wooly Apple Aphid (WAA); Green Apple (Spirea) Aphids (GAA): GAA colonies are beginning to appear in some apple blocks. GAA is generally a pest that can be tolerated since they do little direct damage. Treatment thresholds for GAA are if 50% of the shoots are infested with no beneficial insects present. WAA aerial colonies are present in orchards statewide. We have observed high degrees of parasitism in many orchards and therefore no controls have been needed. Refer to the NJ Commercial Tree Fruit Production Guide for more information.

Potato Leafhoppers (PLH): PLH adults may be still present in apples. PLH should not be tolerated in non-bearing orchards because they can stunt the growth of new shoots. Likewise they should not be tolerated in orchards were fire blight is present because they have been demonstrated to spread the disease. PLH appear as light green smallish leafhoppers and are often found on the new leaves in the growing tips. Neonicitiods are generally recommended for control however there are other broad spectrum materials that are effective. Refer to the NJ Commercial Tree Fruit Production Guide for more information.

Pear Third generation pear psylla began hatching about June 8. Options for control include spynosyn products such as Delegate and Entrust, and the neocitinoids (IRAC group 4A). The addition of 0.25-1 gal of summer oil may improve control. Other options include Movento, the IGR’s Esteem and Centaur, and products containing abamectin. Be sure to read and follow the label instructions regarding the addition of penetrants for abamectin products, and movento. Pear Psylla are still actively laying eggs and nymphs continue to hatch.

Grape: Early blooming native grapes were at trace bloom on 5/24, therefore we have set the the Grape Berry Moth biofix at 5/24 for southern counties. Since V. riparia typically blooms with early natives we used Concord and Ives to set the biofix. The model works best when growers record their own bloom dates and use the Grape Berry Moth model at NEWA. Applications for GBM using Intrepid or Diamides should be made at 810 DD base 47. Other effective materials can be applied a few days later. Applications have been historically made around the end of June in southern counties. As for diseases we are seeing low levels of phomopsis on older leaves in some vineyards.

Phenology Table: Based on annual observations made in Gloucester County.

Pest Event or Growth Stage Approximate Date 2024 Observed Date
 Bud Swell (Redhaven/PF-17)  March 23 +/- 15 Days March 13
1/4″ Green Tip Red Delicious March 31 +/- 13 Days March 18
Pink Peach (Redhaven/PF-17) April 4 +/- 15 Days March 18
Tight Cluster Red Delicious April 9 +/- 13 Days March 30
Full Bloom Peach (Redhaven/PF-17) April 9 +/- 14 Days April 5
Pink Apple (Red Delicious) April 14 +/- 12 Days April 9
Full Bloom Apple (Red Delicious) April 22 +/- 11 Days April 20
Petal Fall (Redhaven) April 22 +/- 10 Days April 15
Petal Fall (Red Delicious) April 27 +/- 13 Days  May 3
Shuck Split (Redhaven) April 30 +/- 11 Days  April 22
Pit Hardening June 15 +/- 9 Days  June 10

 

 

Tree Fruit Trap Captures – Southern Counties

STLM TABM-A CM BMSB OFM-A DWB OFM-P TABM-P LPTB PTB
3/23/2024 70 0
3/30/2024 29 0 0
4/6/2024 421 0 0
4/13/2024 415 7 1
4/20/2024 900 7 0
4/27/2024 312 2 22  1
5/4/2024 137 2 8 27 1 5
5/11/2024 6 2 15 2 1 10 42
5/18/2024 5 6 11 2 6 0 12 41
5/25/2014 33 29 7 4 25 0 44 37
6/1/2024 719 12 12 1 1 0 44 57
6/8/2024 163 7 6 0 27 0 35 52 3

Tree Fruit Trap Captures – Northern Counties

STLM TABM-A CM BMSB OFM-A DWB OFM-P TABM-P LPTB PTB AMBROSIA BEETLE
3/23/2024
3/30/2024
4/6/2024 0 0
4/13/2024 3.25 37.6
4/20/2024 11.75 93
4/27/2024 0 19 50
5/4/2024 1 16 19 124
5/11/2024 3 4 18 112
5/18/2024 4 2 1 2 2 2 83
5/25/2024 7 5 0 16 8 23 55
6/1/2024 16 7 0 28 7 21 37
6/8/2024 17 4 0 23 3 16 2 12