
	Apple Pest Degree Day Calculator

Select a Pest The Base Temperature specific to the pest's phenological model is automatically used, as shown in Table 1.


	Table 1. Pest phenological model base temperatures

Pest	Base T °F
Codling Moth	50
Oriental Fruit Moth	45
Obliquebanded Leafroller	43
Plum Curculio	50
San Jose Scale	50
Spotted Tentiform Leafminer	43
Apple Maggot	50

Confirm the Biofix Date The biofix date automatically used by the Apple Pest Degree Day Calculator is based on historical field observations in New York (Table 2). The biofix date is the date when accumulation of degree days begins for any given phenological model. Skip to step 3 to accept the calculator's biofix date (shown as - - -) or enter a different biofix date here.

Month

Day

Table 2. Historical Approximate Biofix Dates for New York

Pest

Biofix Date

Biofix

Codling Moth

May 19

First sustained trap catch of 1^st generation

Oriental Fruit Moth

May 2

First sustained trap catch of 1^st generation

Obliquebanded Leafroller

June 10

First sustained trap catch of 1^st summer generation

Plum Curculio

May 18

Petal fall (McIntosh)

San Jose Scale

March 1

March 1^st

Spotted Tentiform Leafminer

June 15

First sustained trap catch of 2^nd generation

Apple Maggot

January 1

January 1^st


	Source: Cornell Pest Management Guidelines for Tree Fruit, Table 14. Apple Pest Biofix Table - a pdf file with current observer biofix dates.

Select a Weather Station Location


	Please refer to table at right for months of operation for the weather station you are choosing.

The calculations are made for the current year, from the biofix date to today's date.


		The DD Calculator will detect and display dates with missing data for the weather station selected.



	Reference: Baskerville, G. L. and P. Emin. 1969. Rapid estimation of heat accumulation from maximum and minimum temperatures. Ecology 50: 514-517.


	NEWA Weather Station Beginning Year of Operation and Months Operating as of 2008

	Year Connected	Months Operating
Albion (Orleans county)	2000	Jan - Dec
Appleton, north (Niagara county)	2001	Jan - Dec
Appleton, south (Niagara county)	2001	Apr - Dec
Arkport (Erie county)	1996	Jan - Dec
Avon (Livingston county)	1996	Jan - Dec
Barrington (Yates county)	2001	Jan - Dec
Batavia (Genesee county)	1996	Jan - Dec
Branchport (Yates county)	1996	Jan - Dec
Catatonk (Tioga county)	2003	Jan - Dec
Chazy (Clinton county)	2005	Jan - Dec
CliftonPark (Saratoga county)	2005	Jan - Dec
Clintondale (Ulster county)	2007	Jan - Dec
Dresden (Yates county)	2000	Jan - Dec
Eden (Erie county)	1996	May - Sep
Elba (Genesee county)	1996	Jan - Dec
Farmington (Ontario county)	2003	Jan - Dec
Fredonia (Chautauqua county)	2001	Jan - Dec
Freeville (Tompkins county)	2002	Jan - Dec
Friend (Yates county)	1996	Jan - Dec
Gainesville (Wyoming county)	1996	Jan - Dec
Geneva (Ontario county)	1996	Jan - Dec
Groveland (Livingston county)	1996	Jan - Dec
Guilderland (Albany county)	2001	Jan - Dec
Himrod (Yates county)	1996	Jan - Dec
Ithaca (Tompkins county)	2002	Jan - Dec
Knowlesville (Orleans county)	2001	Apr - Dec
Lansing (Tompkins county)	2002	Jan - Dec
Lyndonville (Orleans county)	2001	Jan - Dec
Mexico (Oswego county)	1997	May - Aug
Naples (Ontario county)	2000	Jan - Dec
Pavilion (Genesee county)	2000	May - Oct
Potter (Yates county)	1996	Jan - Dec
Prattsburg (Steuben county)	1996	May - Oct
Pulteney (Steuben county)	2000	Jan - Dec
Red Hook (Dutchess county)	2005	Jan - Dec
Savannah (Wayne county)	1996	Jan - Dec
Scipioville (Cayuga county)	1998	May - Oct
Scriba (Oswego county)	1996	May - Oct
Sodus (Wayne county)	1996	Jan - Dec
Valois (Schuyler county)	2000	Jan - Dec
Waterport (Orleans county)	2001	Jan - Dec
Watkins Glen (Steuben county)	2007	Jan - Dec
Wayland (Steuben county)	1996	Jan - Dec
Williamson, Motts (Wayne county)	1997	Jan - Dec
Williamson, Mason (Wayne county)	1997	May - Oct

References

Agnello, A. M., D. P. Kain, , and S. M. Spangler. 1993. Fruit pest events and phenological development according to accumulated heat units. NY Food & Life Sciences Bulletin No. 142, 7 pp. Online:http://www.nysaes.cornell.edu/pubs/fls/OCRPDF/142.pdf

Mague, D. L., and W. H. Reissig. 1983. Phenology of the San Jose scale (Homoptera: Diaspididae) in New YorkState apple orchards. Can. Entomol. 115: 717-722.

Onstad, D. W., W. H. Reissig, and C. A. Shoemaker. 1985. Phenology and management of the obliquebanded leafroller (Lepidoptera: Tortricidae) in apple orchards. J. Econ. Entomol. 78: 1455-1462.

Penn. State Univ. 2004. Pennsylvania Tree Fruit Production Guide 2004-2005. ACT AGRS-45, PSU, University Park, PA. p. 103. Online:http://tfpg.cas.psu.edu/part2/part22bv.htm

Reissig, W. H., J. P. Nyrop, & R. Straub. 1998. Oviposition model for timing insecticide sprays against plum curculio (Coleoptera: Curculionidae) in New YorkState. Environ. Entomol. 27: 1053-1061.

Reissig, W. H., J. Barnard, R. W. Weires, E. H. Glass, and R. W. Dean. 1979. Prediction of apple maggot fly emergence from thermal unit accumulation. Environ. Entomol. 8: 51-54.

Riedl, H., B. A. Croft, and A. J. Howitt. 1976. Forecasting codling moth physiology based on pheromone trap catches and physiological-time models. Can. Entomol. 108: 449-460.

Schmaedick, M. A., and J. P. Nyrop. 1995. Method for sampling arthropod pests with uncertain phenology with application to spotted tentiform leafminer (Lepidoptera: Gracillariidae). J. Econ. Entomol. 88: 875-889.