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
Growing degree-days as 5/13/22 – More commonly important pests are highlighted
| Crop type | Common Name | Scientific Name | GDD Min (50F) | GDD Max (95F) | Reference | Developmental / Target Stage |
| Birch | Birch leafminer | Fenusa pusilla | 190 | 290 | RU | Larvae (1st generation) |
| Conifer | Spruce spider mite | Oligonychus ununguis | 190 | 363 | RU | Immatures/Adults |
| Holly | *Native holly leafminer | Phytomyza ilicicola | 192 | 298 | 2 | Egg hatch |
| Andromeda | Andromeda lacebug | Stephanitis takeyai | 192 | 303 | RU | Adults |
| Holly | Holly leafminer | Phytomyza ilicis | 192 | 290 | RU | Egg hatch |
| Honeylocust | Honeylocust pod gall midge | Dasineura gleditchiae | 192 | 229 | RU | Larvae |
| Willows, Cottonwood, Poplar | Imported willow leaf beetle | Plagiodera versicolora | 192 | 448 | RU | Larvae/Adults |
| Larch | Larch sawfly | Pristophora erichsonii | 192 | 299 | 2 | Typical treatment window |
| Privet | Privet thrips | Dendrothrips ornatus | 192 | 618 | 2 | Typical treatment window |
| Rhododendron | Rhododendron borer | Synanthedon rhododendri | 192 | 298 | 2 | Typical treatment window |
| Rhododendron | Rhododendron gall midge | Clinodiplosis rhododendri | 192 | 363 | RU | Larvae |
| Conifer | Cooley spruce gall adelgid | Adelges cooleyi | 200 | 310 | 4 | 1st galls visible – Spruce |
| Conifer | Douglas fir needle midge | Contarinia pseudotsugae | 200 | 400 | 3 | Adults emerge from soil |
| Lilac, ash, privet, many | Lilac / Ash Borer | Podosesia syringae | 200 | 299 | RU | Adults – 1st Treatment |
| Spruce | Spruce budworm | Choristoneura fumiferana | 200 | 300 | 5 | Larvae |
| Elm | Elm leafminer | Fenusa ulmi | 215 | 240 | 5 | Adult emergence |
| Wild and cultivated roses | Roseslug sawfly | Endelomyia aethiops | 230 | – | 6 | Egg hatch / early instars |
| Deciduous, many | Hawthorn lacebug | Corythucha cydoniae | 239 | 363 | RU | Nymphs/Adults |
| Many | Redheaded flea beetle | Systena frontalis | 242 | 600 | Unv. Del | First control target – egg hatch / larval activity |
| Prunus | American plum borer | Euzophera semifuneralis | 245 | 440 | 5 | Adult flight, egg laying |
| Conifer | Arborvitae leafminer | Argyresthia thuiella | 245 | 360 | RU | Larvae Treatments (1st generation) |
| Boxwood | Boxwood mites | Eurytetranychus buxi | 245 | 600 | RU | All Stages |
| Holly | Holly leafminer | Phytomyza ilicis | 246 | 448 | RU | Larvae Treatment |
| Lilac | Lilac leafminer | Caloptilia syringella | 246 | 363 | 5 | Larvae Treatments |
| Conifer | Pine sawflies (Red-headed) | Neodiprion lecontei | 246 | 1388 | RU | Larvae (1st generation) |
| Yew | Taxus mealybug | Dysmicoccus wistariae | 246 | 618 | RU | Adults/Crawlers |
| 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) |
| Many | Spotted Lantern Fly | Lycorma delicatula | 250 | 1000 | PA Dept. Ag | 1st-4th Instar (nymphs) – control target |
| Birch | Birch Leafminer | Fenusa pusilla | 275 | 375 | 4 | Adults laying eggs |
| Boxwood | Boxwood Psyllid | Cacopsylla busi | 290 | 440 | RU | Nymphs |
| Oaks | Kermes oak scale | Allokermes spp. | 298 | 912 | 5 | Typical treatment window |
| Locust | Locust leafminer | Odontota dorsalis | 298 | 533 | 5 | Typical treatment window |
| Conifer | Pine eriophyid mites | Eriophyidae | 298 | 533 | 5 | Typical treatment window |
| Conifer | Pine Needle Scale | Chionaspis pinifoliae | 298 | 448 | RU | Crawlers (1st generation) – control target |
| Privet | Privet Rust Mites | Aculus ligustri | 298 | 802 | RU | All stages |
| Malus | Redbanded leafroller | Argyrotaenia velutinana | 298 | 618 | 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 |
| 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 | 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 |
| 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 |
| Yews, Rhododendrons, many | Black Vine Weevil | Otiorhynchus sulcatus | 400 | 2800 | RU | Adults treatment |
| Conifer | Pine needle midge | Thecodiplosis brachynteroides | 400 | 500 | 7 | Adults (1st generation) |
| Conifer | Pine tortoise scale | Toumeyella parvicornis | 400 | 1000 | 4 | Crawlers |
| Conifer | Striped pine scale | Toumeyella sp. | 400 | 500 | 3 | Crawlers (1st generation) |
| 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) |
| Rhododendron | Azalea whitefly | Pealius azaleae | 448 | 700 | 5 | Adults/nymphs |
| Boxwood | Boxwood Leafminer | Monarthropalpusi flavus | 448 | 700 | RU | Larvae treatment |
| Conifer | Hemlock looper | Lambdina fiscellaria | 448 | 707 | 5 | Typical treatment window |
| Oak | Oak skeletonizer | Bucculatrix ainsliella | 448 | 707 | 5 | Typical treatment window |
| Many | Gypsy moth | Lymanttria dispar | 450 | 900 | 4 | Caterpillar to pupation – control target missed |
| Conifer | Pine Chafer (Anomela Beetle) | Anomala oblivia | 450 | 600 | 7 | Adults (1st generation) |
| Conifer | Pine shoot beetle | Tomicus piniperda | 450 | 500 | 4 | Adults emerge; begin shoot feeding – control target |
| Juniper | Maskell scale | Lepidosaphes pallida | 470 | – | 6 | Crawlers (1st generation) |
| Conifer | European pine shoot moth | Rhyacionia buoliana | 480 | 710 | 5 | Larvae Treatment |
| References | RU | Rutgers Cooperative Extension – Landscape IPM Notes | ||||
| Daily GDD50 = (Max + Min temp.) / 2 – 50 (min temp. threshold) (Simple average growing degree-day, min. 50F, max 95F) | 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)-evolving GDD ranges | |||||
| Compiled by – Timothy J. Waller, Ph.D. – Rutgers Cooperative Extension, Cumberland County Nursery Crops – twaller@njaes.rutgers.edu | ||||||
Additional Scale PPA Posts:
Additional Borer PPA Posts:
