Apple insect pest degree day models

Background Information for this page
Return to Apple list for Easthampton MA
Weather data for Easthampton MA.  Forecast values begin September 18, 2018
Apple Maggot (AM)
     Rough estimate for first apple maggot fly trap capture:   Saturday, June 30.
Estimated 5% AM adult emergence:  July 9.
Estimated date for 50% adult AM emergence & trap captures:   July 26, Thursday
 Peak weekly AM trap captures:   July 31, Tuesday
98% adult AM emergence & trap captures:    August 15, Wednesday
AM emergence and cumulative trap catch dates are only general guidelines
 because local soil type and soil moisture conditions that affect emergence are not included in the calculation.
Borers  -  Roundheaded Appletree Borer (RAB)   &   Dogwood Borer
RAB adult emergence begins:  May 26.    Peak emergence:  June 9.
RAB egglaying begins:  June 2.    Peak egglaying period roughly:  June 24  to July 5. 
First RAB eggs hatch roughly:  June 17.    Peak hatch roughly:  July 9  to July 25.
First Dogwood borer egg hatch roughly:  June 22.    Peak hatch roughly:  July 26.
Codling Moth  (CM)
Codling moth development as of September 18: 
2nd generation egg hatch is completed.
Key codling moth managment dates shown below:
Optimum date to apply RIMON or ESTEEM ovicide/larvicide Insect Growth Regulator (IGR) is shortly before CM egglaying begins (100 CM degree days after start of 1st gen. flight):  May 26. Saturday.
For INTREPID IGR, the optimum first application timing is just before first hatch (150-200 DD):  May 29 to June 1.

For conventional larvicide, Bt, Grandevo, or granulovirus (Cyd-X, Madex etc.),
best timing for first of multiple applications against 1st generation CM is at 3% CM egg hatch (250 DD): 
June 5, Tuesday.

Peak (30% to 70%) 1st generation codling moth egg hatch is from June 16 to June 26.
1st generation 95% egg hatch is around:  July 4. 
      Best date for follow-up application depends on type of material applied
and weather since previous application.  See Codling Moth tables for follow-up spray dates to maintain protection
through 1st generation CM egg hatch.
1st generation 20% CM egg hatch (360 DD):  June 13.
= Target date where a single larvicide application is used to reduce 1st generation CM.
This is also good timing for follow-up to initial IGR application.
2ND GENERATION CM flight begins around July 14. 
Optimum date to apply RIMON or ESTEEM is shortly before 2nd generation CM egglaying begins
(100 DD after 2nd flight start):  July 18.
Best date to apply INTREPID is just before egg hatch (200 DD after 2nd flight start):  July 23.

Best date for first of multiple applications with conventional larvicide, Bt, Grandevo, or granulovirus against 2nd gen.,
 OR for follow-up IGR application is at 2nd gen. 7% egg hatch (360 DD):  July 30.
   
Peak 2nd generation codling moth egg hatch is roughly from August 7 to August 17.
    If needed and allowed by preharvest interval, see Codling Moth tables for follow-up spray dates.
2ND GENERATION 30% CM egg hatch (560 DD after 2nd flight start):  August 7.
= Target date where a single larvicide application is used to reduce 2nd generation CM.
Lesser Appleworm   LAW 
1st LAW flight begins around:  May 14,  Monday.          Peak trap catch:  May 23.
2nd LAW flight begins around:  July 9,  Monday.
Mullein Plant Bug   MPB 
The expected 50% egg hatch date is:  May 16,  Wednesday,
which is 6 days before rough estimate of Red Delicious petal fall date.
Most accurate time for limb tapping counts, or treatment if needed,
but possibly after some MPB damage has occurred,
is 90% egg hatch date:  May 22,  Tuesday.
Obliquebanded Leafroller   OBLR 
1st generation OBLR flight begins around:  June 7,  Thursday.
Where waiting to sample late instar OBLR larvae is not an option
(= where OBLR is known to be a problem,
and will be managed with insecticide against young larvae):
Early egg hatch and optimum date for initial application of B.t., Delegate, Proclaim, Intrepid, Rimon, Altacor, Belt, pyrethroid or other insecticide effective against OBLR
(with follow-up applications as needed):  June 22,  Friday.
Where waiting to sample late instar OBLR larvae to determine need for treatment
is an option, or to check on results from earlier sprays:
Optimum sample date for late instar summer generation OBLR larvae: July 1,  Sunday
If first OBLR late instar larvae sample is below threshold, date for confirmation follow-up:
July 4,  Wednesday.
Oriental Fruit Moth   OFM 

1st generation OFM flight starts:  May 4,  Friday.
1st generation 55% egg hatch and first treatment date, if needed: May 26,  Saturday.
2nd generation OFM flight begins around:  June 27,  Wednesday.
2nd generation - first treatment date, if needed: July 3,  Tuesday.
2nd generation - second treatment date, if needed: July 13,  Friday.
Plum Curculio   PC
 Increased risk of PC damage as McIntosh and similar cultivars increase fruit size:
 May 22,  Tuesday.
 Earliest safe date for last PC insecticide spray:  May 27,  Sunday.
Plum curculio spray intervals
 If relying on repellance by Surround instead of PC mortality by insecticide,  Surround coverage should be maintained until PC egglaying begins to naturally decline around Wednesday, June 27.
Redbanded Leafroller   RBLR 
1st RBLR flight begins around April 24,  Tuesday.
  Peak trap catch and approximate start of egg hatch: May 5, Saturday.
2nd RBLR flight begins around June 28,  Thursday.   
Peak catch and approximate start of egg hatch: July 9.
San Jose Scale   SJS
First adult SJS caught on trap:  May 21,  Monday.
1st generation SJS crawlers appear:  June 12,  Tuesday.
Peak 1st gen. SJS crawlers at June 20,  Wednesday.
Spotted Tentiform Leafminer   STLM
(and presumably apple blotch leafminer)
1st STLM flight, peak trap catch:  May 12,  Saturday.
1st generation sapfeeding mines start showing:  May 22,  Tuesday. 
Optimum sample date is around Wednesday, May 23,
when a larger portion of the mines are visible.
2nd STLM flight begins around:  June 16,  Saturday.
Rough guess of when 2nd generation sap-feeding mines begin showing:  July 3,  Tuesday.  
Optimum first sample date for 2nd generation STLM sapfeeding mines is
July 9,  Monday.
Second optimized sample date for 2nd generation STLM sapfeeding mines, if needed:
July 15,  Sunday.
Third optimized sample date for 2nd generation STLM sapfeeding mines, if needed:
July 25,  Wednesday.
Tarnished Plant Bug    TPB 
Rough guess of when TPB begin showing on traps:  April 26,  Thursday.
Rough guess of when TPB damage results in deformed fruit at harvest
 instead of aborted bud: May 2,  Wednesday.
White Apple Leafhopper   WAL 
1st generation WAL found on apple foliage:  May 15,  Tuesday.
2nd generation WAL found on apple foliage:  August 2,  Thursday.
* Rose leafhopper is easily confused with WAL but has different generation dates.
Rose leafhoppers typically immigrate into orchards from border row host plants
between 1st and 2nd generation WAL.