July Pest Scouting Nursery, Landscape, and Christmas Trees – Key borer and scale insect control timings

Pest Scouting – Please refer to these documents for a full listing of insects pests for your area corresponding to growing degree-days (GDDs). 

Quick look guides for July (Borers and Scales) and (All other) 

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

The following key groups of pests will be active, vulnerable, or otherwise treatable during the next month throughout most of NJ. Here, scale insects and borers with key life stage events during the 1000-2500 GDD timeframe are discussed. Note there are many other insect pests present this time of year so please view the pest scouting guides above for your particular needs.

Projected GDD50 Accumulation as of July 13 2022 Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region Location Station 13-Jul 1-Aug 1-Sep
South Upper Deerfield NJ50 1598 2115 2905
Central Howell / Freehold NJ10 1383 1871 2594
North High Point NJ59 1132 1541 2138
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information 

BORER Insect Activity for 1000-2500 GDD (~ July)
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Roundheaded appletree borer Saperda candida 802 1129 RU Adults
Ash Emerald ash borer Agrilus planipennis 1000 1200 4 Peak adult activity
Many Roundheaded apple tree borer Saperda candida 1514 1798 5 Typical treatment window
Conifer Nantucket tip moth Rhyacionia frustrana 1514 1917 RU Adults 2nd generation
Maple Sugar maple borer Glycobius speciosus 2032 2375 5 Typical treatment window
Locust Locust borer Magacyllene robiniae 2271 2805 5 Typical treatment window
Poplar and Willow Poplar and willow borer Crytorhynchus lapathi 2271 2806 5 Typical treatment window

Click here – “Identifying Clearwing Moth Borers in Pheromone Traps” or “Differentiating the Common Wood Borers of Ash Trees”

SCALE Insect Activity for 1000 – 2500 GDD (~ July)
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Conifer Cryptomeria scale Aspidiotus cryptomeriae 600 800 3 First crawler emergence
Many White prunicola scale Psedaulacaspis prunicola 707 1151 RU Crawlers (1st generation)
Conifer Juniper scale Carulaspis juniperi 707 1260 RU Crawlers (1st generation)
Many Calico scale Eulecanium cerasorum 714 6 Crawlers (1st generation)
Conifer Striped pine scale Toumeyella pini 750 800 4 Egg hatch
Oak, hickory, birch, many Oak leacanium scale Parthenolecanium quercifex 789 6 Crawlers (1st generation)
Acer Cottony maple leaf scale Pulvinaria acericola 802 1265 5 Crawlers (1st generation)
Many, shadetrees Cottony maple scale Pulvinaria innumerabilis 802 1265 RU Crawlers (1st generation) – control target
Oaks Golden oak scale Asterolecanium variolosum 802 1266 5 Egg hatch
Maples Japanese maple scale Lopholeucaspis japonica 829 6 Crawlers (1st generation)
Elm European elm scale Gossyparia spuria 831 1388 6,2 Crawlers (1st generation)
Shade trees European fruit lecanium scale Parthenolecanium corni 932 1645 6,RU Crawlers  – control target
Conifer Pine tortoise scale Toumeyella parvicornis 1000 1200 4 Egg hatch ends, last of crawlers
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 1029 1388 RU Crawlers (1st generation) – control target
Many Indian wax scale Ceroplastes ceriferus 1145 6 Crawlers (1st generation)
Euonymus Euonymus Scale Unaspis euonymil 1150 1388 5 2nd generation targeted treatments
Shade trees European fruit lecanium scale Parthenolecanium corni 1266 1645 5 Crawlers
Conifer Pine Needle Scale Chionaspis pinifoliae 1290 1917 3 Crawlers emerge (2nd generation) – control target
Conifer Hemlock scale Abgrallaspis ithacae 1388 2154 5 Typical treatment window
Malus, Prunus, many Peachtree borer Synanthedon sp. 1500 1800 RU Larvae Treatment
Many White prunicola scale Pseudaulacaspis prunicola 1637 6 Egg hatch / crawler (2nd generation)
Euonymus Euonymus Scale Unaspis euonymil 1700 RU Continued 2nd generation treatments
Conifer Cryptomeria scale Aspidiotus cryptomeriae 1750 2130 RU, 4 Crawlers emerge (2nd generation)
Many Obscure scale Melanaspis obscura 1774 6 Egg hatch / crawler
Conifer Maskell scale lepidosaphes pallia 2035 6 Egg hatch / crawler (2nd generation)
Mainly Tulip Tulip tree scale Toumeyella liriodendri 2037 2629 RU Crawlers (1st generation)
Mainly Magnolia Magnolia scale Neolecanium cornuparvum 2155 2800 RU Crawlers (1st generation)
Maple Japanese maple scale Lopholeucaspis japonica 2508 6 Egg hatch / crawler (2nd generation)
Conifer Elongate hemlock scale Fiorinia externa 2515 2625 RU Typical treatment window – fall activity
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 2515 2800 RU Fall control of overwintering stage

[Read more…]

Nursery Pests Scouting June – Bagworms, Scales, Borers, RHFB, BWB


Red-headed flea beetle – Adult emergence beginning any day now

Please refer to this timeline of pest development compiled by Tim Waller in communication with Brain Kunkel (Unv. Del) and Danny Lauderdale (NC State)

  • Contains material selection and timing, along with regime information and considerations

Boxwood Blight Alert – Infection Potential (Saturday) 5/27

Boxwood Blight Risk Assessment as of 5/24/2022
Region Location CODE 24-May 25-May 26-May 27-May 28-May 29-May
Southern Upper Deerfield NJ50 Very Low  Very Low  Low  High Risk Very Low  Very Low 
Central Howell / Freehold NJ10 Very Low  Very Low  Low  Infection Risk Very Low  Very Low 
Northern High Point NJ59 Very Low  Very Low  Very Low  Infection Risk Very Low  Low 
Check local boxwood blight risk here (CLICK HERE – input your area code – select closest weather station – check 7-14 prediction – click on graph / table)

 

Refer to the most recent Alert for more information – CLICK HERE


Pest Scouting – Please refer to these documents for a full listing of insects pests for your area corresponding to growing degree-days (GDDs). 

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

The following key groups of pests will be active, vulnerable, or otherwise treatable during the next month throughout most of NJ. Here, bagworms, scale insects and borers with key life stage events during the 350-1500 GDD timeframe are discussed. Note there are many other insect pests present this time of year so please view the pest scouting guides above for your particular needs.

Projected GDD50 accumulation as of 5/24/2022 (USPEST) Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region Location Station 24-May 1-Jun 1-Jul
South Upper Deerfield NJ50 488 638 1358
Central Howell / Freehold NJ10 426 551 1203
North High Point NJ59 288 387 909
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information 

BAGWORMS (600-900 GDD) (Bagworm hatch prediction as of 5/24/22 – now until July 14 (Southern NJ (NJ50)))
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Conifer mostly, many minor hosts Bagworm Thyridopteryx ephemeraeformis 600 900 RU Larvae (early instars) –

ONLY CONTROL WINDOW

Refer to this post for additional information on Bagworms

BORER Insect Activity for 350 – 1500 GDD (Now until ~July 1 in Southern NJ (NJ50))
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Malus, Prunus, many Lesser peach tree borer Synanthedon pictipes 350 375 4 Adult flight, egg laying
Dogwood, apple, pecan, elm, hickory, willow Dogwood borer Synanthedon scitula 350 850 4 adults, eggs, caterpillars
Birch Bronze Birch Borer Agrilus anxius 440 880 RU Adults (egg laying)
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
Malus, Prunus, many Greater peach tree borer Synanthedon exitiosa 575 710 4 Adult emergence
Many Roundheaded appletree borer Saperda candida 802 1129 RU Adults
Ash Emerald ash borer Agrilus planipennis 1000 1200 4 Peak adult activity
Malus, Prunus, many Peachtree borer Synanthedon sp. 1500 1800 RU Larvae Treatment
Many Roundheaded apple tree borer Saperda candida 1514 1798 5 Typical treatment window
Conifer Nantucket tip moth Rhyacionia frustrana 1514 1917 RU Adults 2nd generation

Click here – “Identifying Clearwing Moth Borers in Pheromone Traps” or “Differentiating the Common Wood Borers of Ash Trees”

[Read more…]

Pest Scouting 200-500 GDD – Get sprayers ready for Borers, Scale Crawlers, and other important pests

It’s that time of year again, many scale crawlers and borers will be active over the next few weeks throughout NJ. Be prepared to target specific pest life-stages for the highest level of efficacy per material cost and get those problem insects in check. Application of contact insecticides during specific activity windows for these pests should be coupled with systemic applications now to help protect woody plants later on.

Borers attack stressed plants. If you recently dug then heeled-in trees, transplanted seedlings, or otherwise seriously stressed a tree, please consider taking immediate action to protect them from both adult flights (contact trunk sprays) and future infestations (systemics)   

Please Download these resources: (The scouting guide is for you to print and keep on hand…these are just updates)

Nursery and Landscape Pest Scouting Guide 2022 PDF (note this contains conifer pests as well)

Conifer Pest Scouting Guide 2022 PDF

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

Projected GDD50 accumulation as of 5/13/2022 Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region Location Station 13-May 1-Jun 1-Jul
South Upper Deerfield NJ50 297 603 1323
Central Howell / Freehold NJ10 242 508 1160
North High Point NJ59 135 345 867
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information 

[Read more…]

Nursery – Pest Scouting Guide for August – Reminders – Need a few more nurseries for Phytophthora sampling

NURSERY PEST SCOUTING GUIDE – August (1300-2200 GDD50)

Please download and print the pest scouting guide resource (printable version of the information below for your desk or truck) –(click on the link and then print)

Projected GDD50 accumulation as of 8/4/2021
Region Location 1-Aug 1-Sep 1-Oct 1-Nov
Southern Upper Deerfield (NJ50) 2145 2931 3477 3682
Central Howell / Freehold (NJ10) 1896 2630 3109 3249
Northern High Point (NJ59) 1490 2045 2352 2384
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

 

(Same material as downloads)

Pest Scouting – Growing Degree-day Ranges  (1600-3000 GDD50) 
CROP TYPE Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Redheaded flea beetle Systena frontalis 1570 1860 Udel. 2nd generation egg hatch
Many Two-banded Japanese weevil Pseudocneorhinus bifasciatus 1644 2271 RU Adults
Willow Willow twig aphids Lachnus spp. 1644 2271 5 Typical treatment window
Conifer Juniper webworm Dichomeris marginella 1645 1917 RU Larvae Treatment
Euonymus Euonymus Scale Unaspis euonymil 1700 RU Prophylactic 2nd generation treatments
Conifer Cryptomeria scale Aspidiotus cryptomeriae 1750 2130 RU, 4 Crawlers emerge (2nd generation)
Many Obscure scale Melanaspis obscura 1774 6 Egg hatch / crawler
Oaks Oak skeletonizer Bucculatrix ainsliella 1798 2155 RU Larvae
Conifer Arborvitae leafminer Argyresthia thuiella 1800 2200 RU Larvae Treatment (3rd generation)
Mimosa, Honeylocust Mimosa webworm Homadaula anisocentra 1800 2100 RU Larvae (2nd generation)
Conifer Cooley spruce gall adelgid Adelges cooleyi 1850 1950 RU Galls open (Spruce)
Many Redheaded flea beetle Systena frontalis 1878 2318 Udel. 2nd generation Adults feeding
Turf Hairy chinch bug  Blissus leucopterus 1903 2160 RU Second generation- 50%- 2nd instars
Tulip Tuliptree aphid Illinoia liriodendri 1917 2033 RU Nymphs
Conifer Zimmerman pine moth Dioryctria zimmermani 1917 2154 5 Treatment window (adult flight-1700 GDD)
Mainly Oaks Orangestriped oakworm Anisota senatoria 1917 6 Egg hatch – early instars
Conifer White pine aphid Cinara strobi 1991 2271 RU Adults
Rhododendron Azalea whitefly Pealius azaleae 2032 2150 5 Adults/nymphs (3rd generation)
Maple Sugar maple borer Glycobius speciosus 2032 2375 5 Typical treatment window
Conifer Maskell scale lepidosaphes pallia 2035 6 Egg hatch / crawler (2nd generation)
Mainly Tulip Tulip tree scale Toumeyella liriodendri 2037 2629 RU Crawlers (1st generation)
Mainly Magnolia Magnolia scale Neolecanium cornuparvum 2155 2800 RU Crawlers (1st generation)
Euonymus Euonymus Scale Unaspis euonymil 2235 6 Egg hatch / crawler (2nd generation)
Locust Locust borer Magacyllene robiniae 2271 2805 5 Typical treatment window
Poplar and Willow Poplar and willow borer  Crytorhynchus lapathi 2271 2806 5 Typical treatment window
Conifer Spruce spider mite  Oligonychus ununguis 2375 2806 5 Typical treatment window – fall activity
Many Southern red mite Oligonychus ilicis 2500 2700 5 Typical treatment window
Maple Japanese maple scale Lopholeucaspis japonica 2508 6 Egg hatch / crawler (2nd generation)
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 2515 2800 RU Fall control of overwintering stage
Conifer Elongate hemlock scale  Fiorinia externa 2515 2625 RU Typical treatment window – fall activity
Hardwoods Fall webworm Hyphantria cunea 2793 6 Egg hatch / crawler (2nd generation)
Conifer Cooley spruce gall adelgid Adelges cooleyi 2800 3000 3 Fall control of overwintering stage
Conifer Eastern spruce gall adelgid Adelges abietis 2800 3000 3 Fall control of overwintering stage
Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed. References 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
Daily GDD50 =                                                                                                  (Max + Min temp.) / 2 – 50 (min temp. threshold) 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)-evolving GDD ranges
Compiled 8-04-2021 – Timothy J. Waller, Ph.D. – Rutgers Cooperative Extension, Cumberland County Nursery Crops – twaller@njaes.rutgers.edu

 


Redheaded flea beetle considerations:

Adults should be surfacing any day in the southern regions of the state. However, in two sentinel plot locations I have yet to see second generation adults as of 8/3/2021.

Contact materials aimed at managing developing larvae (especially growth regulators) may be particularly useful at this time. Contact materials or fast acting systemics should be used to target adults in the next few days to weeks. The use of long lasting systemics should also be considered to protect foliage from the next generations adults (if a third generation occurs) and again late season to guard from first generation adults in the 2022 spring season.

These GDD estimates and corresponding calendars are evolving as we continue to learn more about this pest. If you have high populations please contact Tim Waller so we can continue to adapt our recommendations in NJ.  Email: twaller@njaes.rutgers.edu

Please refer to this updated RHFB timeline printout for your desk or truck (as of 842021) (CLICK HERE)

 


SURVEY REQUESTS

WE NEED A FEW MORE FARMS!! 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

Nursery – Pest Scouting Guide for July – BWB and RHFB Reminders

NURSERY PEST SCOUTING GUIDE – JULY (1300-2200 GDD50)

Please download and print the pest scouting guide resources (printable version of the information below for your desk or truck) –(click on the link and then print)

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

Projected GDD50 accumulation as of 7/1/2021
Region Location 1-Jul 1-Aug 1-Sep 1-Oct 1-Nov
Southern Upper Deerfield (NJ50) 1303 2145 2931 3477 3682
Central Howell / Freehold (NJ10) 1102 1896 2630 3109 3249
Northern High Point (NJ59) 884 1490 2045 2352 2384
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

 

(Same material as downloads)

Nursery Pest Scouting – Growing Degree-day Ranges  (1300-2200 GDD50) 
CROP TYPE Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Japanese beetle  Popillia japonica 950 2150 5 Adults emerge and feed
Turf Bluegrass billbug Sphenophorus parvulus 1094 1217 RU Larvae (40%)
Many Indian wax scale Ceroplastes ceriferus 1145 6 Crawlers (1st generation)
Many Oriental Beetle Anomala orientalis 1147 6 Adult emergence
Euonymus Euonymus Scale Unaspis euonymil 1150 1388 5 2nd generation targeted treatments
Dogwood Dogwood sawfly Macremphytus tarsatus 1151 1500 RU Larvae Treatment
Tulip Tuliptree aphid Illinoia liriodendri 1151 1514 RU Nymphs / adults
Boxwood Boxwood leafminer  Monoarthropalpus flavus 1200 1400 5 Larvae Treatment
Conifer Northern pine weevil Pissodes nemorensis 1200 1400 4 2nd generation adults active
Conifer Pales weevil Hylobius pales 1200 1400 4 Adults 2nd generation
Conifer Pine root collar weevil  Hylobius radicis 1200 1400 4 2nd generation adults active
Conifer White pine weevil Pissodes strobi 1200 1400 4 2nd generation adults active
Rhododendron Azalea whitefly Pealius azaleae 1250 1500 5 Adults/nymphs (2nd generation)
Turf Bluegrass sod webworm Parapediasia teterrella 1250 1920 RU Larvae
Birch Birch Skeletonizer Bucculatrix canadensisella 1266 1580 5 Typical treatment window
Shade trees European fruit lecanium Parthenolecanium corni 1266 1645 5 Crawlers
Many Fall webworm Hyphantria cunea 1266 1795 2 Caterpillars present – larvae treatment
Many Lacebugs ( on hawthorn) Corythucha cydoniae 1266 1544 RU Nymphs / adults
Many Leafhoppers Species within Cicadellidae  1266 1544 RU Nymphs / adults
Privet Privet rust mite Aculus ligustri 1266 1515 5 Second typical treatment window
Conifer Pine Needle Scale Chionaspis pinifoliae 1290 1917 3 Crawlers emerge (2nd generation)
Many Two spotted spider mite  Tetranychus urticae 1300 2000 RU Nymphs / adults
Turf N. Masked chafer Cyclocephala borealis 1377 1579 RU Adults (90%)
Conifer Hemlock scale Abgrallaspis ithacae 1388 2154 5 Typical treatment window
Lilac Lilac leafminer  Caloptilia syringella 1388 1644 5 Typical treatment window
Conifer Cooley spruce gall adelgid Adelges cooleyi 1500 1775 RU Adults/nymphs (Douglas Fir)
Malus, Prunus, many Peachtree borer Synanthedon sp. 1500 1800 RU Larvae Treatment
Conifer Pine Needle Scale Chionaspis pinifoliae 1500 4 Hyaline crawlers = treatment timing
Conifer Nantucket tip moth Rhyacionia frustrana 1514 1917 RU Adults 2nd generation
Many Roundheaded apple tree borer Saperda candida 1514 1798 5 Typical treatment window
Many Redheaded flea beetle Systena frontalis 1570 1860 Udel. 2nd generation egg hatch
Many Japanese beetle  Popillia japonica 1590 1925 RU Adults (90%)
Many White prunicola scale Pseudaulacaspis prunicola 1637 6 Egg hatch / crawler (2nd generation)
Conifer Rust-mites  Nalepella and Setoptus spp. 1644 2030 RU Nymphs / adults
Many Two-banded Japanese weevil Pseudocneorhinus bifasciatus 1644 2271 RU Adults
Willow Willow twig aphids Lachnus spp. 1644 2271 5 Typical treatment window
Conifer Juniper webworm Dichomeris marginella 1645 1917 RU Larvae Treatment
Euonymus Euonymus Scale Unaspis euonymil 1700 RU Continued 2nd generation treatments
Conifer Cryptomeria scale Aspidiotus cryptomeriae 1750 2130 RU, 4 Crawlers emerge (2nd generation)
Many Obscure scale Melanaspis obscura 1774 6 Egg hatch / crawler
Oaks Oak skeletonizer Bucculatrix ainsliella 1798 2155 RU Larvae
Conifer Arborvitae leafminer Argyresthia thuiella 1800 2200 RU Larvae Treatment (3rd generation)
Mimosa, Honeylocust Mimosa webworm Homadaula anisocentra  1800 2100 RU Larvae (2nd generation)
Conifer Cooley spruce gall adelgid Adelges cooleyi 1850 1950 RU Galls open (Spruce)
Turf Hairy chinch bug  Blissus leucopterus 1903 2160 RU Second generation- 50%- 2nd instars
Tulip Tuliptree aphid Illinoia liriodendri 1917 2033 RU Nymphs
Conifer Zimmerman pine moth Dioryctria zimmermani 1917 2154 5 Treatment window (adult flight-1700 GDD)
Mainly Oaks Orangestriped oakworm Anisota senatoria 1917 6 Egg hatch – early instars
Conifer White pine aphid Cinara strobi 1991 2271 RU Adults
Rhododendron Azalea whitefly Pealius azaleae 2032 2150 5 Adults/nymphs (3rd generation)
Maple Sugar maple borer Glycobius speciosus 2032 2375 5 Typical treatment window
Conifer Maskell scale lepidosaphes pallia 2035 6 Egg hatch / crawler (2nd generation)
Mainly Tulip Tulip tree scale Toumeyella liriodendri  2037 2629 RU Crawlers (1st generation)
Mainly Magnolia Magnolia scale Neolecanium cornuparvum 2155 2800 RU Crawlers (1st generation)
Locust Locust borer Magacyllene robiniae 2271 2805 5 Typical treatment window
Poplar and Willow Poplar and willow borer  Crytorhynchus lapathi 2271 2806 5 Typical treatment window
Conifer Spruce spider mite  Oligonychus ununguis 2375 2806 5 Typical treatment window
Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed. References 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
Daily GDD50 =                                                                                                  (Max + Min temp.) / 2 – 50 (min temp. threshold) 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)-evolving GDD ranges
Compiled 7-6-2021 – Timothy J. Waller, Ph.D. – Rutgers Cooperative Extension, Cumberland County Nursery Crops – twaller@njaes.rutgers.edu  

Redheaded flea beetle considerations:

Adults are mating and laying eggs in southern NJ. Contact material applications are still viable to target adults now (if found scouting) but will also be useful when treating larvae prior to emergence from the soil/growing media in a few weeks time. The use of systemics should also be considered to protect foliage from the next generations adults and again late season to guard from first generation adults in the 2022 spring season.

NOTE: The majority of RHFB I have personally observed have been seen later in the evening, especially if the foliage is wet. I have also isolated an anthracnose pathogen (Colletotrichum sp.) from what appeared to be damaged leaves. Thus a complete fungicide – insecticide program needs to be in place if this is a high value crop for your business.

Refer to this chart for material and timing considerations (GDD50 forecasts updated 7/6/2021) – CLICK HERE


Boxwood blight considerations: 

Preventative applications should continue in high value plantings. As with the vast majority of foliar diseases, overhead irrigation plays a major role in reducing the staying power and efficacy of fungicides. Overhead irrigation or rain events also play a critical role in pathogen dispersal and ease of entry by these pathogens into plant tissues. Anything you can do to reduce/limit overhead irrigation in virtually all crops will aid in reducing the overall disease pressure that your plants experience.

Boxwood Blight Risk Model (CLICK HERE) – 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) 

Great new resources by Steve Rettke

Mimosa Webworm Activity Begins

Some Key Soft Scale Pests in the Landscape


SURVEY REQUESTS

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