Pest and disease action calendar

Time/growth stage Check list of Integrated Pest and Disease Management tasks

Dormant Period

  Assess overwintering populations of rust mite behind growing shoot buds, fruit tree red spider mite winter eggs round spurs, aphid and sucker eggs on shoots and scale insects on bark. Earmark orchards with damaging populations of any of these pests for treatment at the appropriate time.
  Remove badly cankered branches, wood scab and mildew infected (silvered) shoots, root stock sucker growths (which may harbour capsid eggs) during winter pruning. Protect pruning wounds with suitable canker paint
  Check whether any leaf litter is left in the orchard by the end of February as this may be a source of scab inoculum. Macerate thoroughly well before bud burst to aid biodegradation.
  Service and calibrate weather station. Start temperature records from 1 January.
  Stock check pesticide store.
Just pre bud-swell
  Consider a pre-bud-burst spray of a copper fungicide (check current approval status), especially where canker and scab were bad the previous season. This may give some control of overwintering scab and protect against Neonectria canker.
Bud-swell
  Start weather station records of leaf wetness, humidity and rainfall. Run disease forecasting (e.g. RIMpro) and pest life cycle computer models at least weekly and before spray rounds are applied.
  Start programme of fungicide sprays for scab control promptly. Choice of fungicide and spray interval will depend on varietal susceptibility, scab levels the previous season including late season infection of leaves and the amount of leaf litter present.
Bud-burst
  Monitor populations of apple blossom weevil adults at edges of orchards using beating method if pest was present previous season. Apply a spray of chlorpyrifos (Dursban etc.) in good conditions if threshold exceeded
  Continue sprays for scab to maintain good protection at this sensitive stage
Mouse ear
  Monitor numbers of rust mites on outer rosette leaves. If threshold (5 mites per outer leaf) is exceeded, apply acaricide, or include sulphur at reduced (25-33%) rate in next 3-4 spray rounds
  Continue sprays for scab to maintain good protection at this sensitive stage
Green cluster
  Conduct pre-blossom pest assessment for aphids, winter moth, tortrix moth, caterpillars, apple sucker, capsids, rust mite and other minor pests. Apply pre-blossom insecticide spray if necessary.
  Start mildew spray programme. Choice of product, dose, volume and interval will depend on varietal susceptibility and mildew levels last year
  Continue sprays for scab to maintain good protection at this sensitive stage
Pink bud
  Check truss leaves for scab until early June. Early detection of a potential problem is essential.
  Assess primary mildewed flower trusses. >2% indicates a problem, >10% a severe problem. Use eradicant mildew fungicide.
  Put out white sticky traps for sawfly adults.
First Flower
  Continue spray programme for scab and mildew as necessary
  Apply first spray for blossom wilt. Repeat 7 days later. Cox, James Grieve, Lord Derby and several cider varieties are very susceptible.
Full bloom
  Continue spray programme for scab and mildew as necessary, but try to avoid spraying fungicides at this critical time if possible
Late blossom
  Continue spray programme for scab and mildew as necessary
  Conduct late blossom pest assessment for rosy apple aphid, sawfly, winter moth, clouded drab moth, fruit tree red spider mite, rust mite and capsid, and capped blossoms due to apple blossom weevil.
End of blossom
  Continue spray programme for scab and mildew as necessary.
  Assess primary mildewed vegetative terminal buds. >2% indicates a problem, >10% a severe problem. Use good eradicant mildew fungicide, decrease spray interval and increase spray volume if a problem.
  Check for signs of wilting, dying blossoms due to blossom wilt. Cut out affected trusses now while they can be seen and before cankers form. Earmark problem orchards for treatment the following year.
  Check for early signs of collar rot in older orchards on susceptible rootstocks. Early detection means the tree can be saved.
  Apply post blossom insecticide spray if required for capsid, sawfly, winter moth, clouded drab moth, rosy apple aphid or other pests.
  Apply acaricide spray for rust mite or fruit tree red spider mite if necessary
  In orchards where leaf midge has been a severe problem and where establishment of the parasitic wasp Platygaster demades is to be encouraged, start monitoring numbers of leaf midge eggs in growing points twice weekly in a representative orchard until harvest. Avoid spraying broad-spectrum insecticides when midge eggs are numerous to avoid harming the adult parasite, which is active when leaf midge eggs are numerous.
  Set out pheromone traps for codling, fruit tree tortrix moth and summer fruit tortrix moth. Record the catch of moths of each species at least weekly.
Early June
  Check orchard thoroughly for signs of scab on leaves or fruitlets and for wood scab. Continue sprays as necessary if scab is present, or if the weather is very wet or if scab problems occurred last year
  Monitor secondary mildew in shoots regularly, at least fortnightly, ideally before each spray round. Continue mildew sprays until the extension growth has ceased. Adjust rate and interval according to the levels of mildew present, the favourability of the weather for mildew and the rate of growth of the trees.
  In orchards where canker is a problem, apply a spray, e.g. captan, to protect leaf scars from canker during summer leaf fall. Sprays at this time may reduce Neonectria rots in store.
  Conduct early June pest assessment for rosy apple aphid, woolly aphid, rosy leaf curling aphid (look out next year), sawfly damage (earmark for treatment next year), clouded drab moth, fruit tree red spider mite, rust mite.
  Continue frequent monitoring of leaf midge eggs where required. Avoid using broad-spectrum insecticide sprays when eggs are numerous to avoid harming Platygaster demades.
  If Blastobasis was present last year or infestation is suspected, conduct beat samples for adults at fortnightly intervals throughout June or July. Insecticidal treatment should be considered if the pest is detected.
  Calculate daily egg development amounts for summer fruit tortrix using maximum and minimum air temperatures and look up table provided. Apply egg hatch spray of suitable insecticide when sum reaches 90‑100%. Repeat sprays to maintain protection through egg hatch period. This action should not be necessary if fenoxycarb (Insegar) was used just before and, if necessary, just after blossom.
  Continue weekly monitoring of pheromone traps for codling and tortrix moths. If methoxyfenozide (Runner) or indoxacarb (Steward) is to be used, which is advisable if Blastobasis is a problem the first spray should be delayed until the start of egg hatch.
Late June
  Continue monitoring secondary mildew in shoots regularly, at least fortnightly, ideally before each spray round. Continue mildew sprays until the extension growth has ceased. Adjust rate and interval according to the levels of mildew present, the favourability of the weather for mildew and the rate of growth of the trees.
  Continue sprays for scab only if necessary.
  Look for signs of die back on extension growth caused by canker. Cut out and burn.
  Conduct late June pest assessment for woolly aphid, green apple aphid, fruitlet mining tortrix, fruit tree red spider mite, rust mite. Apply control treatments as necessary.
  Continue weekly monitoring of pheromone traps for codling and tortrix moths.  If methoxyfenozide (Runner) or indoxacarb (Steward) is to be used, which is advisable if Blastobasis is a problem, the first spray should be delayed until the start of egg hatch.
  Continue frequent monitoring of leaf midge eggs where required. Avoid using broad-spectrum insecticide sprays when eggs are numerous to avoid harming Platygaster demades.
  Continue regular beat sampling for Blastobasis if necessary. Apply methoxyfenozide (Runner) or indoxacarb (Steward) sprays if pest is detected.
July-August
  Continue monitoring secondary mildew in shoots regularly, at least fortnightly, ideally before each spray round. Continue mildew sprays until the extension growth has ceased. Adjust rate and interval according to the levels of mildew present, the favourability of the weather for mildew and the rate of growth of the trees.
  Continue sprays for scab only if necessary
  In orchards where a risk of Neofabraea rot or Phytophthora rot has been determined, apply sprays of a recommended fungicide at 2-3 week intervals to protect fruit against infection.
  Conduct late July-mid August pest assessment for woolly aphid, green apple aphid, fruit tree red spider mite, rust mite. Apply control treatments as necessary.
  Continue frequent monitoring of leaf midge eggs where required. Avoid using broad-spectrum insecticide sprays when eggs are numerous to avoid harming Platygaster demades.
  Continue regular beat sampling for Blastobasis adults throughout July if necessary. Apply methoxyfenozide (Runner) or indoxacarb (Steward) sprays if pest is detected, or if it was a problem in the previous year.
Pre-harvest
  Conduct rot risk assessment in each orchard. Determine best way of minimising losses due to rots.
Harvest
  Train pickers to be vigilant for pest and disease blemishes to fruit and record the causes of significant losses in each orchard. Be vigilant for sawfly and Blastobasis damage.
Post-harvest
  In orchards with a high level of scab, apply a spray of 5% urea post picking and before appreciable leaf fall. This will help aid microbial breakdown of the leaves bearing scab pseudothecia and prevent the overwintering stage of scab developing.
Leaf fall
  To protect leaf scars from canker infection, apply an approved fungicide spray the start of leaf fall and again at 50% leaf fall.
Grading
  Train grading staff to be vigilant for pest and disease blemishes to fruit and fungal rots and record the causes and extent (% incidence) of losses due to each cause in each orchard.
Dormant period
  Go to top of table and start again. Practice makes perfect!