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): 

• Pest Scouting Guide August 2021 (1600-300 GDD₅₀ )
• To determine your local growing degree-days, please review this post “Obtaining your local growing degree-day information”

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

 

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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)

 

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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