Degree Days

What are degree days?

Growing degree days (DD) are a weather-based indicator for assessing crop and pest development. It is a calculation used by crop producers that measures heat accumulation used to predict plant and pest development rates. Growing degrees are defined as the mean daily temperature (average of daily maximum and minimum temperatures) above a certain threshold base temperature accumulated on a daily basis over a period of time. Daily growing degree day values are added together from the beginning of the season. Degree day totals are also used for comparing the progress of a growing season to the long-term average.

Degree Day Development Table

The codling moth, like all insects, is cold blooded. Meaning, the temperature around it determines how fast it grows and how active it is as an adult moth. We can take advantage of this to predict what life stage the majority of the codling moths population are in. Scientists have developed a model that uses degreedays to predict codling moth development. These predictions are summarized in this table.

Degree day total
(+/- 3-5 DD)
Codling moth stage of development
100Emergence of 1st brood moths from overwintering larvae
150Beginning of 1st brood egg laying
220Start of 1st egg hatch (first brood larvae)
500End of emergence of 1st brood moths
575Start of emergence of 2nd brood moths
650End of 1st brood egg hatch
700Start of 2nd brood egg hatch (2nd brood larvae)
1140End of 2nd brood moth emergence
1160Start of 3rd brood moth emergence
1275End of 2nd brood egg hatch
1300Start of 3rd brood egg hatch

A complete codling moth degree day development table is also available as a PDF – Full Codling Moth Degree Day Development Table.

More information about the codling moth stages of development, see Codling Moth.

Degree Day Tables

The degree day totals in the table below indicate the predicted stage of development of codling moth populations near specific weather stations located around the valley. Growers and advisors can use the values to determine the life stages of the codling moth in their area. This will help determine the proper time to apply ovicidal and larvicidal products to control each of the codling moth generations if needed.

  • 2016 Degree Days - South
    Weather Station Location
    OsoyoosOliver SouthOliver NorthCawstonKeremeosPentictonSummerland
    September 6, 20161490132313751485149912381276
    September 2, 20161459129713481462147512141254
    August 31, 20161438127813291439145311951231
    August 29, 20161415126813181428144011741211
    August 26, 20161378123312811387139811401172
    August 24, 20161356121112611364137311211151
    August 22, 20161334119112411344135011021132
    August 19, 20161292115412031301130510661092
    August 17, 20161274112511711268127210511076
    August 15, 20161230109611411236124010101032
    August 11, 2016117889694010021005964981
    August 8, 20161146876921974983936949
    August 3, 20161083856900956957889897
    August 2, 20161071847890947947870878
    July 29, 20161012833876931931818823
    July 27, 2016983804848901900790794
    July 25, 2016955791835886884767768
    July 20, 2016900759802851850718718
    July 18, 2016888738786830828709708
    July 15, 2016845708751802799672674
    July 11, 2016802669709765763637637
    July 8, 2016773653694751749613613
    July 6, 2016756645686741738600601
    July 4, 2016735636677733731582583
    June 30, 2016674581624676673535534
    June 28, 2016647568609662659513511
    June 24, 2016613544582640636484482
    June 22, 2016593526562621617467466
    June 20, 2016581515550620606456455
    June 17, 2016565503536604590442443
    June 15, 2016559498530599585437437
    June 13, 2016546487517586572428428
    June 9, 2016514462492559545401402
    June 6, 2016470419449510496361357
    June 3, 2016436389416472458331326
    June 1, 2016417373398454440315310
    May 30, 2016406363388444429307302
    May 27, 2016385351375434418295292
    May 25, 2016369337360416398280278
    May 24, 2016362331352410391275273
    May 20, 2016342312334394374259259
    May 19, 2016334303325385364252251
    May 16, 2016309281301360336230230
    May 13, 2016285261278338312212212
    May 11, 2016274250267327300203202
    May 9, 2016262238257N/A289192192
    May 7, 2016241221237N/A266178176
    May 4, 2016215198213N/A242158154
    May 2, 2016200184199N/A225145141
    April 29, 2016183168182N/A207132128
    April 27, 2016173158172N/A196123120
    April 25, 2016164151164N/A188116113
    April 22, 2016137128139N/A1619894
    April 20, 2016121112122N/A1398379
    April 19, 2016113104114N/A1317672
    April 15, 20161009199N/A1166460
    April 6, 2016595559N/A713632
    March 30, 2016321718N/A231713
    Data from Osoyoos, Penticton and Summerland comes from Environment Canada.
    Data from Oliver south, Oliver north, Cawston, and Keremeos comes from Growers Supply's weather network.
  • 2016 Degree Days - Central
    Weather Station Location
    WestbankKelowna SouthKelowna EastBelgoGlenmoreEllison
    September 6, 2016130212841308127412161199
    September 2, 2016127612591283125111921176
    August 31, 2016125312371263122811731158
    August 29, 2016124412281254122011641150
    August 26, 2016120711921218118511321120
    August 24, 2016118511701198116711151102
    August 22, 2016116811521180115010971085
    August 19, 2016112811141142111110641053
    August 17, 2016109910861114108110391027
    August 15, 2015107010561085105310121002
    August 11, 2016859841876840812806
    August 8, 2016839820855820793787
    August 3, 2016816796833796770764
    August 2, 2016806787824787762756
    July 29, 2016791772809772748743
    July 27, 2016763743784744721717
    July 25, 2016750729770731708705
    July 20, 2016716696736698677673
    July 18, 2016697676716679659654
    July 15, 2016675651690654634630
    July 11, 2016636612650618598592
    July 8, 2016622598636604585579
    July 6, 2016614591629596577571
    July 4, 2016606583622590570564
    June 30, 2016554532570538N/A514
    June 28, 2016541518557525N/A501
    June 24, 2016517496533503N/A478
    June 22, 2016500479515485N/A462
    June 20, 2016487468504475N/A451
    June 17, 2016473455490463N/A438
    June 15, 2016466449483458N/A431
    June 13, 2016455439471447N/A420
    June 9, 2016429413447423N/A398
    June 6, 2016384370402378N/A358
    June 3, 2016355340371346N/A331
    June 1, 2016339324355330N/A316
    May 30, 2016331315345321N/A308
    May 27, 2016321305335313N/A300
    May 25, 2016305289319298N/A285
    May 24, 2016299282312292N/A279
    May 20, 2016284269297279N/A266
    May 19, 2016275264288271N/A258
    May 16, 2016248237262245N/A235
    May 13, 2016228218242228N/A219
    May 11, 2016218207231218N/A211
    May 9, 2016207202222210N/A203
    May 7, 2016190182206193N/A188
    May 4, 2016170166185172N/A169
    May 2, 2016156151170157N/A155
    April 29, 2016142136155144N/A143
    April 27, 2016134128146136N/A135
    April 25, 2016126120138129N/A127
    April 22, 2016106102119109N/A109
    April 20, 2016918710290N/A93
    April 19, 201684799482N/A86
    April 15, 201671667868N/A72
    April 6, 201639364536N/A40
    March 30, 20161011159N/A16
    Data from Westbank, Kelowna South, Kelowna East, Belgo, Glenmore and Ellison comes from Growers Supply's weather network.
  • 2016 Degree Days - North
    Weather
    Station
    Location
    OyamaWinfield SouthOK Landing & Bella VistaVernon North & BX Salmon Arm
    September 6, 201611121220125112131129
    September 2, 201610921200122911931110
    August 31, 201610771178120611731091
    August 29, 201610691170118611541072
    August 26, 201610431138115411231045
    August 24, 201610271120113611071029
    August 22, 201610121105111910911012
    August 19, 2016984106710831057982
    August 17, 2016961104010551030969
    August 15, 2016938N/A10271003932
    August 11, 2016762N/A830938888
    August 8, 2016745N/A808907856
    August 3, 2016725N/A786861812
    August 2, 2016718N/A777843795
    July 29, 2016706N/A755794748
    July 27, 2016682N/A727766721
    July 25, 2016671N/A714740700
    July 20, 2016643N/A681689659
    July 18, 2016626N/A661670638
    July 15, 2016604N/A635645601
    July 11, 2016572N/A600609569
    July 8, 2016559N/A586588545
    July 6, 2016553N/A579575533
    July 4, 2016546N/A574561519
    June 30, 2016502N/A525511476
    June 28, 2016491N/A511497454
    June 24, 2016469N/A489476423
    June 22, 2016455N/A472458412
    June 20, 2016445495461448402
    June 17, 2016433469447433390
    June 15, 2016428462440427384
    June 13, 2016419452430417376
    June 9, 2016397428404395345
    June 6, 2016363386362350313
    June 3, 2016337368332321288
    June 1, 2016324352316306276
    May 30, 2016317345309299270
    May 27, 2016308337302290262
    May 25, 2016295321285273248
    May 24, 2016289316280268243
    May 20, 2016275291265256226
    May 19, 2016
    268291258248219
    May 16, 2016246274233224198
    May 13, 2016231247217206182
    May 11, 2016221237207197173
    May 9, 2016213227198189161
    May 7, 2016199199182174148
    May 4, 2016180179161154127
    May 2, 2016166165145139115
    April 29, 2016151152133128104
    April 27, 201614214312411998
    April 25, 201613413611611292
    April 22, 2016117117979579
    April 20, 2016101100797867
    April 19, 20169485727160
    April 15, 20167962585746
    April 6, 20164633293126
    March 30, 2016197101213
    Data from Salmon Arm comes from Environment Canada.
    Data from Oyama, Winfield South, OK Landing & Bella Vista, and Vernon North & BX comes from Growers Supply's weather network.