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): 

• Nursery Pest Scouting Guide (1300-2200) GDD₅₀
• Mid-season Conifer Specific Pest Scouting Guide (600-2200) GDD₅₀

To determine your local growing degree-days, please review this post “Obtaining 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

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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

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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) 

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Great new resources by Steve Rettke

Mimosa Webworm Activity Begins

Some Key Soft Scale Pests in the Landscape

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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