Do you have Phytophthora at your conifer nursery / Christmas tree farm? We are still looking for a few more participants in a statewide study – aimed at better RECS.

Tim Waller (Cumberland Co.) and Bill Errickson (Monmouth Co.) of Rutgers Cooperative Extension are looking for 30 conifer producers to collaborate in a statewide Phytophthora sampling project, as part of a Specialty Crop Block Grant. This study will focus on identifying the species of Phytophthora limiting conifer production in New Jersey.

  • If your operation is selected, the agents will schedule one to three visits this growing season to collect samples from roots, bark, soil, irrigation systems, and will perform soil testing (Year 1).
  • During years 2 and 3, we will be performing chemical, biological, and cultural disease management trials in addition to conifer variety trials, at Rutgers-NJAES experiment stations. The aim is to generate local data – using local isolates in order to develop a more wholistic set of recommendations when targeting this disease in our NJ nurseries.

The agents also look forward to developing stronger relationships throughout New Jersey in the post-COVID19 era

This project is open to nurseries and Christmas tree farms producing conifers in NJ 

If you are interested in this project – please respond via this brief survey (click here) 

Please print and share this PDF survey with anyone not online (click here)

 

Please contact Tim Waller – twaller@njaes.rutgers.edu – (856-451-2800) – for more information

Nursery and Conifer Pest Scouting Guide: 250-600 GDD & Boxwood Blight Information & Request for Collaborators

Please print or download these resources (click on them)

General Nursery Scouting (contains conifer information within range

Conifer / Christmas Tree Specific Pest Scouting Guides

To determine your local growing degree-days, please review this postObtaining your local growing degree-day information”

Projected GDD50 accumulation as of 5/5/2021
Region Location 5-May 1-Jun 1-Jul 1-Aug 1-Sep
Southern Upper Deerfield (NJ50) 308 665 1342 2184 2970
Central Howell / Freehold (NJ10) 208 511 1132 1926 2660
Northern High Point (NJ59) 127 315 767 1373 1928
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

 

Pest Scouting – Growing Degree-day Ranges (240-600 GDD50)
CROP TYPE Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Redheaded flea beetle Systena frontalis 242 600 Unv. Del First control target – egg hatch / larval activity
Conifer Arborvitae leafminer Argyresthia thuiella 245 360 RU Larvae Treatments (1st generation)
Prunus American plum borer Euzophera semifuneralis 245 440 5 Adult flight, egg laying
Boxwood Boxwood mites Eurytetranychus buxi 245 600 RU All Stages
Lilac Lilac leafminer Caloptilia syringella 246 363 5 Larvae Treatments
Holly Holly leafminer Phytomyza ilicis 246 448 RU Larvae Treatment
Yew Taxus mealybug Dysmicoccus wistariae 246 618 RU Adults/Crawlers
Conifer Pine sawflies (Red-headed) Neodiprion lecontei 246 1388 RU Larvae (1st generation)
Boxwood Boxwood leafminer Monarthropalpusi flavus 249 6 Adult emergence
Conifer Eastern spruce gall adelgid Adelges abietis 250 310 5 Egg hatch, galls begin forming (not a control target)
Birch Birch Leafminer Fenusa pusilla 275 375 4 Adults laying eggs
Boxwood Boxwood Psyllid Cacopsylla busi 290 440 RU Nymphs
Conifer Pine Needle Scale Chionaspis pinifoliae 298 448 RU Crawlers (1st generation) – control target
Locust Locust leafminer Odontota dorsalis 298 533 5 Typical treatment window
Conifer Pine eriophyid mites Eriophyidae 298 533 5 Typical treatment window
Malus Redbanded leafroller Argyrotaenia velutinana 298 618 5 Typical treatment window
Privet Privet Rust Mites Aculus ligustri 298 802 RU All stages
Oaks Kermes oak scale Allokermes spp. 298 912 5 Typical treatment window
Conifer Pine root collar weevil Hylobius radicis 300 350 4 1st adults active
Conifer Turpentine beetle Dendroctonus terebrans 300 350 4 Parent beetles colonizing brood material
Spirea Spirea aphid Aphis spiraecola 326 6 Adults/nymphs
Conifer Hemlock Woolly Adelgid Adelges tsugae 350 350 RU Eggs and 50% hatch
Malus, Prunus, many Lesser peach tree borer Synanthedon pictipes 350 375 4 Adult flight, egg laying
Rhododendron Azalea Lacebug Stephanitis pyrioides 350 646 RU Adults (1st generation)
Dogwood, apple, pecan, elm, hickory, willow Dogwood borer Synanthedon scitula 350 850 4 adults, eggs, caterpillars
Conifer Elongate Hemlock Scale Fiorinia externa 360 700 RU Crawlers (1st generation)
Elm Elm Leaf Beetle Xanthogaleruca luteola 363 530 RU Larvae treatment (1st generation)
Conifer Larch casebearer Coleophora laricella 363 618 2,4 Nymphs active – typical treatment window
Many Oystershell Scale Lepidosaphes ulmi 363 707 RU Crawlers
Walnut Walnut blister mite Eriophyes erinea 363 707 5 Typical treatment window
Beech Woolly beech aphids Grylloprociphilus imbricator & Phyllaphis fagi 363 7070 5 Typical treatment window
Conifer Striped pine scale Toumeyella sp. 400 500 3 Crawlers (1st generation)
Conifer Pine needle midge  Thecodiplosis brachynteroides 400 500 7 Adults (1st generation)
Conifer Pine tortoise scale Toumeyella parvicornis 400 1000 4 Crawlers
Yews, Rhododendrons, many Black Vine Weevil Otiorhynchus sulcatus 400 2800 RU Adults treatment
Basswood Basswood lacebug Gargaphia tiliae 415 6 Adults/nymphs
MANY Fourlined plant bug Poecilocapsus lineatus 435 6 Egg hatch / early instars
Many Two-Spotted Mite Tetranychus urticae 437 997 RU Adults (build-up activity)
Birch Bronze Birch Borer Agrilus anxius 440 880 RU Adults (egg laying)
Boxwood Boxwood Leafminer Monarthropalpusi flavus 448 700 RU Larvae treatment
Rhododendron Azalea whitefly Pealius azaleae 448 700 5 Adults/nymphs
Oak Oak skeletonizer Bucculatrix ainsliella 448 707 5 Typical treatment window
Conifer Hemlock looper Lambdina fiscellaria 448 707 5 Typical treatment window
Conifer Pine shoot beetle Tomicus piniperda 450 500 4 Adults emerge; begin shoot feeding – control target
Conifer Pine Chafer (Anomela Beetle) Anomala oblivia 450 600 7 Adults (1st generation)
Many Gypsy moth Lymanttria dispar 450 900 4 Caterpillar to pupation – control target missed
Juniper Maskell scale Lepidosaphes pallida 470 6 Crawlers (1st generation)
Conifer European pine shoot moth Rhyacionia buoliana 480 710 5 Larvae Treatment
Malus, Prunus, many Peach Tree Borer Synanthedon sp. 500 600 RU Adults – emerge (1st treatment both types)
Rhododendron Rhododendron Borer Synanthedon rhododendri 509 696 RU Adults emerge
Many White prunicola scale Psedaulacaspis prunicola 513 6 Crawlers (1st generation)
Many Redheaded flea beetle Systena frontalis 517 1028 Unv. Del Adults – feeding / laying eggs
Many Cottony camellia / taxus scale Pulvinaria floccifera 520 6 Crawlers (1st generation)
Birch Birch Leafminer Fenusa pusilla 530 700 RU Larvae (2nd generation)
Conifer Arborvitae Leafminer Argyresthia thuiella 533 700 RU Adults (egg laying) – larvae treatments
Euonymus Euonymus Scale Unaspis euonymil 533 820 RU Crawlers (1st generation)
Oak Oak blotch leafminers Cameraria spp. ; Tisheria spp. 533 912 5 Typical treatment window
Maple Greenstriped mapleworm Dryocampa rubicunda 533 1645 5 Control target
Conifer Balsam gall midge Paradiplosis tumifex 550 700 4 Galls apparent
Conifer Juniper scale Carulaspis juniperi 550 700 7 Egg hatch
Malus, Prunus, many Greater peach tree borer Synanthedon exitiosa 575 710 4 Adult emergence
Conifer Cryptomeria scale Aspidiotus cryptomeriae 600 800 3 First crawler emergence
Conifer Bagworm Thyridopteryx ephemeraeformis 600 900 RU Larvae (early instars) – ONLY CONTROL WINDOW
Conifer Cooley spruce gall adelgid Adelges cooleyi 600 1000 7 Nymphs active – Douglas fir (control target)
RU Rutgers Cooperative Extension – Landscape IPM Notes
2 http://ccetompkins.org/resources/using-growing-degree-days-for-insect-management
3 https://extension.psu.edu/ipm-basics-for-christmas-trees#section-2
4 https://www.canr.msu.edu/ipm/agriculture/christmas_trees/gdd_of_conifer_insects
5 https://www.agriculture.nh.gov/publications-forms/documents/landscape-pests.pdf
6 https://extension.umd.edu/ipm/pest-predictive-calendar-landscapenursery
7 https://www.canr.msu.edu/ipm/agriculture/christmas_trees/gdd_of_landscape_insects
Unv. Del. Coorespondance with Dr. Kunkel (University of Delaware)

 

Boxwood Blight risk-model information, considerations, and links:

Boxwood Blight Risk Assessment as of 5/5/2021
Region Location CODE 4-May 5-May 6-May 7-May 8-May 9-May
Southern Upper Deerfield NJ50 Infection Risk Infection Risk Very Low  Very Low  Very Low  Very Low 
Central Howell / Freehold NJ10 Low  Low  Very Low  Very Low  Very Low  Very Low 
Northern High Point NJ59 Very Low  Very Low  Very Low  Very Low  Very Low  Very Low 
Please check your local boxwood blight risk here (click here and type in your area code – select closest station)

 

Wednesday 5/4/21 -PPA Post regarding boxwood blight activity (click here)

  • These advisories are general in nature and change rapidly so someone from your business should be using this risk model (CLICK HERE) daily if boxwood is important to your financial stability – In 30 seconds you can have a better idea of boxwood blight (and other pathogen) activity in your immediate area!
    • (click on the link – input area code – select closest weather station – check 7-14 prediction – click on graph / table) 

 

Phytophthora sampling and Redheaded Flea Beetle survey requests (5-minutes to take both)

Please answer a few questions if you would like to be included in a statewide Phytophthora in Conifer Nurseries sampling project 

Please fill out this brief survey if you are experiencing damages due to Redheaded flea beetle (RHFB)

Contact – Timothy J. Waller – twaller@njaes.rutgers.edu for more information

Early Season Conifer and Christmas Tree Pest Scouting List Using Growing Degree-days (base 50F)

Please print or download the two resources of this post (click on them)

The information provided in the downloads gives early season scouting ranges (in growing degree days, base 50F) for specific insect pests harming conifer and Christmas tree production and maintenance. Additionally, forecasting predictions (GDD50 accumulation) for calendar dates of multiple regions of New Jersey (S,N,C) are provided.

To determine your local growing degree-days, please review this postObtaining your local growing degree-day information”

Scouting Ranges:

  • This document supports scouting, it does not replace it. Keeping good notes on pest development will help dial in scouting and treatment efforts at your local level.
  • It is important to note that these GDD50 are not exact, rather provide a range of GDD and subsequent calendar dates that can be used to scout for, and treat for, insect pests.
  • The pests listed here will be listed again in future scouting range announcements as they undergo further developmental life stages or are vulnerable to management options.
  • If you need more information, OR you are regularly seeing specific pest development stages at growing degree-days different than those listed here, please contact Tim Waller at twaller@njaes.rutgers.edu

 

Projected GDD50 accumulation as of
NJ Region Location March 1st April 1st May 1st June 1st July 1st
Southern Upper Deerfield (NJ50) 0 24 133 540 1217
Central Howell / Freehold (NJ10) 0 14 95 443 1064
Northern High Point (NJ59) 0 1 7 220 672
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

 

Early Season Conifer Pest Scouting – Growing Degree-day Ranges Starting (0-300 GDD50)
Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Conifer rust mites Eriophyidae 7 22 4 Overwintering eggs hatch
Eastern pine weevil Pissodes nemorensis 7 58 RU Overwintering adults become active / prevent egg laying
Taxus mealybug Dysmicoccus wistariae 7 91 2 Spring control of overwintering stage
Cottony taxus scale Pulvinaria floccifera 7 91 6 Spring control of overwintering stage
Elongate hemlock scale Fiorinia externa 7 120 2 Spring control of overwintering stage
Spruce spider mite Oligonychus ununguis 7 121 RU Overwintering eggs hatch
Pales weevil Hylobius pales 7 121 RU Overwintering adults become active / prevent egg laying
White pine aphid Cinara strobi 22 91 RU Spring control of overwintering stage
Pine bark adelgid Pineus strobi 22 58 2 Spring control of overwintering stage
Spruce bud scale Physokermes piceae 22 120 2 Spring control of overwintering stage
Juniper scale Carulaspis juniperi 22 148 2 Spring control of overwintering stage
Eastern spruce gall adelgid Adelges abietis 25 100 3 spring control of overwintering stage
Northern pine weevil Pissodes approximatus 25 100 4 1st adults active
Zimmerman pine moth Dioryctria zimmermani 25 100 3 1st larvae active
Cooley spruce gall adelgid Adelges cooleyi 25 120 3 Spring control of overwintering stage
White pine weevil Pissodes strobi 25 220 4 1st adults active
European pine sawfly Neodiprion sertifer 35 145 1 Spring control of overwintering stage
Fletcher scale Parthenolecanium fletcheri 35 148 2 Spring control of overwintering stage
European pine shoot moth / borer Rhyacionia buoiana 50 220 4 1st larvae active
Pine tortoise scale Toumeyela parvicornis 58 148 2 Cralwer activity
Pine bark adelgid Pineus strobi 58 618 2 Spring control of overwintering stage
Balsam twig aphid Mindarus abietinus 60 100 4 Egg hatch
Eastern pine shoot borer Eucosma gloriola 75 200 4 1st adults active
Cooley spruce gall adelgid Adelges cooleyi 90 180 4 1st adults active – Douglas fir
Balsam twig aphid Mindarus abietinus 100 150 4 Stem mothers present (control target)
Pine engraver (Ips bark beetle) Ips spp. 100 150 4 1st adults active
European pine sawfly Neodiprion sertifer 100 195 4 1st larvae active
Larch casebearer Coleophora laricella 120 150 4 Egg hatch
Nantucket pine tip moth Rhyacionia frustrana 121 448 RU 1st generation egg hatch
Gypsy moth Lymantria dispar 145 200 4 Egg hatch, 1st larvae
Spruce spider mite Oligonychus ununguis 150 175 4 1st egg hatch
Spruce needleminer Endothenia albolineana 150 200 4 1st larvae active
Balsam gall midge Paradiplosis tumifex 150 300 4 Adults laying eggs
Spruce budworm Choristoneura fumiferana 200 300 4 1st larvae active
Cooley spruce gall adelgid Adelges cooleyi 200 310 4 1st galls visible – Spruce
Arborvitae leafminer Argyresthia thuiella 245 360 4 Larvae in mines; 1st generation
Eastern spruce gall adelgid Adelges abietis 250 310 4 Egg hatch, galls begin forming
Pine needle scale Chionaspis pinifoliae 298 448 4 1st generation egg hatch
Pine root collar weevil Hylobius radicis 300 350 4 1st adults active
Turpentine beetle Dendroctonus terebrans 300 350 4 Parent beetles colonizing brood material
References RU Rutgers Cooperative Extension – IPM Notes
2 http://ccetompkins.org/resources/using-growing-degree-days-for-insect-management
3 https://www.canr.msu.edu/ipm/agriculture/christmas_trees/gdd_of_conifer_insects
4 https://extension.psu.edu/ipm-basics-for-christmas-trees#section-2
5 https://www.agriculture.nh.gov/publications-forms/documents/landscape-pests.pdf
6 https://extension.umd.edu/ipm/pest-predictive-calendar-landscapenursery

(Please note: we will be providing pest GDD ranges regularly throughout the season for our green industries)

 

Important notes about growing degree-day models:

  1. These models do not replace scoutingThey should guide scouting efforts and pest management programs, once the vulnerable life stage or economic threshold of a pest is recorded. Observations at a local level for specific pests is critical to IPM efforts and further refinement of degree-day-based predictions.
  2. GDD50 values for pest development are not exact, rather they should be viewed as a range. 
  3. The growing degree-day model (GDD50) is general by design. Some insect pests have specific formulas for their growth and development (some examples here). However, the GDD50 model is useful for many pests and plant species.
  4. Many GDD50 target values were developed in other parts of the country and should be ‘ground truthed’ at a local level. Blind applications of pesticides, without truthing pest development, may not deliver desired outcomes.

 

Rusty, but never Crusty

Last week I had the pleasure of attending New Jersey Christmas Tree Growers’ Association Annual Twilight Meeting at Black Oak Farm in Asbury, New Jersey.

New Jersey Christmas Tree growers share tips on tree care during NJCTGA twilight meeting at Black Oak Farm. Photo: Tim Dunne

New Jersey Christmas Tree growers share tips on tree care during NJCTGA twilight meeting last week at Black Oak Farm. Photo: Tim Dunne

[Read more…]

Attention Christmas Tree Growers!

Buds of many confiers, including Douglas-fir, are in the process of breaking around the state. Every spring around this time, the Plant Diagnostic Laboratory starts to get samples with suspect needlecast, and as usual, we have indeed seen our share of needlecast so far this spring.

Needlecast. Photo: Marty McMekin, Mt. Bethel Tree Farm

Needlecast. Photo: Marty McMekin, Mt. Bethel Tree Farm

[Read more…]

Hold on to Your Needles!

As the weather warms, Christmas tree growers and nursery folks are beginning to get back into their fields to select trees for digging or to assess field conditions. Recent samples in the Plant Diagnostic Laboratory suggest it would be prudent to keep an eye out for disease symptoms and signs that would have appeared or intensified over the winter. [Read more…]