Orchard management:   Synopsis of key early season dates

Background Information for this page
Return to Apple list for Easthampton MA
Weather data for Easthampton MA.  Forecast values begin August 3, 2017

   Green text is for horticultural events and management activities.
 
  Red is for insect pest events.
   Brown is for mite pest events.
   Blue is for disease events.
Highest priority growing season activities are highlighted in yellow boxes.
Date  Early Season Biological Events and Management Activities

January 1, Sun

    Peak of 1st generation Spotted tentiform leafminer flight.
Before
bud break

   Check tractor and sprayer for needed repairs.
   Replace worn nozzles, weak hoses, damaged or blocked filters, and inaccurate pressure gauges.  Check for tank leaks, adequate agitation and pump function.
   Check commonly used dosage calculations.  Review safety guidelines, check safety equipment.
  
Calibrate sprayers, test spray pattern, test pH of spray water source.

April 11, Tue
 
McIntosh trees at 50%
Green Tip (observed)

    Where
copper deficient, foliar application recommended at green tip to 1/4" green.  Later application can cause leaf burn and possibly lead to fruit russetting from residue.
    If monitoring tarnished plant bug, traps should be set by now or as soon as possible.
    If using traps to monitor
leafminers, traps should be set by now or as soon as possible.
  
Cutworm defoliation of emerging buds can be a problem on young trees as early as green tip, especially where there is high ground cover growth near the trees.

April 12, Wed

   First primary apple scab infection period.  See Scab ratings tables and charts for details.

April 16, Sun
 
McIntosh trees at Half-Inch Green
 
 Beginning of optimum time window for oil application to smother European red mite eggs before they hatch.
  
More than 3 thrips per fruit bud can decrease fruit set.
   Effective timing for Lorsban trunk application to get season-long suppression of
insect borers.
April 16, Sun
    First primary scab infection period on or after Half Inch Green.  Infection risk increases as green tissue expands.

April 18, Tue

    Beginning of 1st generation Spotted tentiform leafminer flight

April 24, Mon
 
McIntosh Tight Cluster
   First of two
foliar urea applications for possible fruit set improvement is timed for tight cluster to pink (2nd is after petal fall).
   Where
zinc is deficient, first of two zinc chelate applications recommended at tight cluster (2nd is second cover spray after petal fall).

 Tarnished plant bug damage beyond this point leaves damaged fruit on tree: 
    retail crop threshold - cumulative average 5 per trap
    wholesale crop threshold - cumulative average 3 per trap
 
Leafminer thresholds:
   McIntosh - cumulative average 4 per trap
   other cultivars - cumulative average 8 per trap.
Tight Cluster to Pink thresholds for other pests: 
   
Green fruit worm - 5 larvae per 100 fruit clusters.
  
 Green pug moth - 6 larvae per 100 fruit clusters.
   
Obliquebanded leafroller - 2+ larvae in first 30 fruit clusters or vegetative terminals, 3+ in 100 (can stop looking if there are none in first 50)
  
 Rosy apple aphid - 1 or more colonies per 100 fruit clusters.
  Watch for
Tent caterpillars on low-spray trees.
 
 Where Powdery mildew is a concern, check 100 terminals per block (10 per tree x 10 trees).  Between Tight cluster and 1 week after Petal fall, threshold is 10% infected terminals.  Threshold indicates need for treatment because of high risk for subsequent yield reduction and fruit infections.
  

April 25, Tue
 
McIntosh Open Cluster
   As good a time as any to set out shingles to establish
vole monitoring stations for late summer and fall use.  A few stations in border rows is better than none.  A full block survey requires stations in every 4th tree in a center row, and one station per row in a diagonal line across the block.
 
 Set European apple sawfly traps.

April 28, Fri
 
1st generation European red mite egg hatch begins
   Prebloom oil treatment still worthwhile, but loses some efficacy as eggs hatch progresses.

April 28, Fri
 
McIntosh full
extended Pink
 Tarnished plant bug thresholds: 
     retail - cumulative average 8 per trap
     wholesale - cumulative average 5 per trap
 
Leafminer thresholds:
     McIntosh - cumulative average 9 per trap
     other cultivars - cumulative average 21 per trap.

 
Pink stage is control opportunity for TPB, mullein bug, rosy apple aphid, green fruitworm where these pests are over threshold.
   Pink insecticide application may also suppress European apple sawfly, Plum curculio, leafrollers and other caterpillars.

April 28, Fri
 
    Gypsy moth eggs hatch into larvae (rough guess)
    Gypsy moth feeding on buds can cause serious defoliation on young trees with no prior insecticide coverage, Bt is an option if treatment needed before petal fall.

April 29, Sat
 
McIntosh King Bloom
   
See Fire blight tables and charts for early warning of blossom blight infection conditions.

April 30, Sun

 Date of earliest High or Extreme fire blight blossom infection risk where inoculum abundant.

May 2, Tue
  
McIntosh Full Bloom
   
Apogee for vegetative growth control and reduced susceptibility to fire blight shoot infection should be applied when the most vigorous shoots are 1 to 2 inches long.  This usually coincides with late bloom - petal fall.
    Weed competition in the tree row is most damaging to tree growth and productivity in the prebloom-bloom-early summer period. 
Postemergence burndown herbicides are more effective and lower end of rate range can be used when weeds are small: <6" for Gramoxone (paraquat), <8" for Rely (glufosinate), < 12" for Roundup (glyphosate). 
 
  If monitoring Codling moth, set pheromone traps.
    Best time to find blooming wild rosaceous pest-host trees in woods within 50-100 meters of orchard and tag for later removal.

May 12, Fri

    1st generation White apple leafhopper (WAL) nymphs present.

May 13, Sat

   McIntosh 95% Petal Fall (estimated or observed)
 
 European apple sawfly thresholds:
      block without prebloom insecticide - 4 to 5 per trap
      block with prebloom insecticide - 6 to 9 per trap.

  
 Monitor Plum curculio damage if delaying insecticide past petal fall.
 
  Threshold for 1st generation European red mites is an average of 1 mite per leaf, or mites present on more than 30% of middle-aged fruit cluster leaves.  Suppression is more effective if done before 2nd generation eggs are laid.
  
 Consider Calyx end rot control in fungicide selection if bloom period had prolonged wet cloudy weather.
    Petal fall is end of optimum fungicide control window for
Powdery mildew.  Continue monitoring until terminal bud set.  Date for terminal bud set varies by cultivar, tree age, and nutritional status, but is generally around 6-8 weeks after Petal fall.
  

May 13, Sat

   Mullein plant bug egg hatch at 50%, best time for limb tap sampling, especially where there is block history of damage.  Threshold:  8 nymphs per 20 limbs tapped over 2-foot-square dark tray.

May 15, Mon
 
McIntosh at about 100% Petal Fall
  See
Thinning Weather table and chart to identify optimum conditions and to help adjust rates for chemical thinning.
   Second of two
foliar urea applications for possible fruit set improvement is timed for petal fall to 7 days after petal fall.
   Where
magnesium deficient, foliar application is recommended for petal fall, first and second cover sprays (risk of phytotoxicity if temperature > 80F or if slow drying conditions).

May 15, Mon
 
    White apple leafhopper threshold  - 1 per leaf, lower if leafhoppers were a problem at harvest last year.
  
 Obliquebanded leafroller - Last opportunity to control spring generation of larvae.  Threshold:  2+ larvae in first 30 fruit clusters or vegetative terminals, 3+ in 100 (can stop looking if there are none in first 50).
     Although the ideal timing may be different for each pest, insecticide application at petal fall also helps control rosy apple aphid, tarnished plant bug, codling moth, green fruitworm, leafrollers, and roundheaded
apple tree borer.
May 16, Tue
   First date after Petal Fall with increased sensitivity for chemical thinner application.

May 18, Thu
 
1st generation Spotted tentiform leafminer sap-feeding mines start showing.
   Thresholds vary between states:  
      McIntosh & stressed trees: 7 to 50 mines per 100 leaves;   
      other cultivars and unstressed trees: 14 to 100 mines per 100 leaves.

May 18, Thu
 
 McIntosh Fruit Set
   Good time to recheck that
sprayer calibration is still on target after early season sprays.
   First cover spray is timing for
manganese foliar application where deficient.  One of many boron application times, boron recommendations are too complex for this table. 
 
  Increased risk of Plum curculio damage.
   Usually best time for scouting 1st generation
Spotted tentiform leafminer mines as more of the first generation mines have had time to appear, but still early enough for effective control even with systemic insecticide options that require application within two weeks after petal fall for best absorption.
 
 Where Powdery mildew is a concern, check 100 terminals per block (10 per tree x 10 trees).  Finding more than 20% infected terminals between fruit set and terminal bud set indicates weakness in control program and high risk for yield reduction and fruit infection next season.  Date for terminal bud set varies by variety, tree age and nutritional status, but is generally around 6-8 weeks after Petal fall.

May 24, Wed

     Date by which blossom blight symptoms would become obvious if fire blight blossom infection occurred on April 30.

May 25, Thu

     Best-guess date for 95% scab ascospore release (50:50 chance that true value is higher or lower).  Reasonable estimate for depletion of primary scab infection risk in blocks where low scab inoculum was documented with scab index the previous fall.

May 25, Thu

     Date of final primary scab ascosore release ('final' defined as best guess that 99+% of ascospores have been released, with high probability that at least 95% have been released.)

May 29, Mon
   
   Date by which 50% of primary scab potential has had time to begin appearing as 1st generation foliar lesions.  Good time for intensive scab scouting.  Finding 5 or more infected leaves per 100 fruit cluster clusters in a commercial orchard suggests need for increased fungicide protection to suppress spore production from lesions and to protect leaves and fruit from secondary infections.  It also indicates need to identify cause for breakdown in protection.  Common causes are inadequate fungicide coverage, timing, or dosage.

June 1, Thu

    If using pheromone traps to time sampling for Obliquebanded leafroller larvae, time to set traps.  First trap capture expected in 7 days.

June 1, Thu

    ERM threshold increases to 2.5 mites per leaf, or mites present on 59% of middle-aged fruit cluster leaves, until July 1.  See ERM sampling table for optimum scouting intervals.

June 6, Tue

   Earliest safe date for final Plum curculio insecticide spray.  See Plum curculio table and charts.

June 7, Wed
    
    Roundheaded apple tree borers begin laying eggs.
    Young trees or other trees not receiving insecticide for other pests need to have protection by a physical barrier or trunk insecticide on or before this date.

June 7, Wed
 
    If using pheromone traps to time sampling for 2nd generation Spotted tentiform leafminer, time to set traps.  First trap capture expected in 7 days.
June 8, Thu
    Recommended timing to begin calcium foliar sprays at two week intervals to prevent early summer cork spot and late summer bitter pit before harvest, and to decrease senescent breakdown in storage.  Increased calcium level may also decrease chance of storage scald.
    Where
zinc is deficient, second of two zinc chelate applications recommended for 2nd cover spray after petal fall.

June 8, Thu
 
     Date by which ALL primary scab infection periods have had time to begin appearing as 1st generation lesions.  Finding scab infections on fewer than 5 leaves per 100 clusters/shoots suggests that primary scab control was successful.  If there is doubt about primary scab control, continue sampling for 2nd generation lesions before relaxing protection against secondary scab.  Light infestation of 1st generation lesions can be difficult to detect.  Infections delayed but not killed by fungicide application or partial resistance of older leaves may appear later.
    Finding more than 5 leaves with fresh scab lesions per 100 fruit clusters and vegetative shoots in a commercial orchard at this time suggests that fungicide selection and spray intervals need to be adjusted to suppress spore production, and need to protect fruit and foliage for at least 4 weeks until active scab lesions exhaust their supply of spores.

June 9, Fri
 
    1st generation Codling moth 3% egg hatch.  Codling moth control typically provided by insecticide applications against plum curculio and apple maggot.  If separate codling moth control is needed, and Bt or other material requiring repeated applications for control is being used, this is best date for first application.  See Codling moth tables for follow-up spray dates to maintain protection through 1st generation CM egg hatch.
   No reliable threshold:  Go by block history.  Another risk indicator is pheromone trap capture above 5 to 14 codling moths per week.

June 9, Fri

    Second generation European red mite nymphs appear.
    An important monitoring period is between now and June 12 to detect above threshold population before 3rd generation eggs are laid. 

June 10, Sat

    Date by which 50% of primary scab potential has had time to begin appearing as 2nd generation lesions on foliage and fruit.  Finding more than 5 scab-infected leaves per 100 fruit clusters or vegetative shoots in a commercial orchard suggests need for fungicide applications to suppress spore production, and to protect fruit and foliage for at least 4 weeks until active scab lesions exhaust their supply of spores.  It also indicates need to identify cause for breakdown in protection.  Common causes are inadequate fungicide coverage, timing, or dosage.

June 11, Sun
  
    End of Plum curculio insecticidal control period.

June 11, Sun

     Date shoot blight symptoms would become obvious if fire blight blossom infection occurred on April 30.

June 12, Mon

    Earliest 2nd generation European red mite adults begin laying 3rd generation eggs.
June 12, Mon
   Date canker blight symptoms on vegetative shoots near overwintered fire blight cankers would show

June 13, Tue
 
    1st generation Codling moth - best date for single spray (estimated 20% egg hatch) where separate control needed.
    No reliable threshold:  Go by block history.  Another risk indicator is pheromone trap capture above 5 to 14 codling moths per week.
mid-June to
mid-July

   Most effective timing for controlling persistent weeds (bindweed, brambles, dandelion, goldenrod, vetch etc.) with Gramoxone (paraquat) or Rely (glufosinate).
 
 Green apple aphid populations typically become more apparent at this time.  Effective biocontrol in most orchards limits threat to young trees for which maximum growth is desired.  Treatment threshold on established trees is if more than 50% of shoots are infested AND less than 20% of aphid colonies have predators.

June 18, Sun

     Date shoot blight symptoms caused by inoculum from canker blight infections (not from blossom infection) would show

June 28, Wed
 
   Date by which 2nd generation Flyspeck spores start becoming available, increasing risk of infections that will show by harvest.  In low-flyspeck-risk blocks, continuous protection may not be needed prior to this date.  See Flyspeck tables for optimum spray intervals and definition of low-risk blocks.