Publication 360, Fruit Production Recommendations: Apple Calendar - Petal Fall (Calyx) when most petals have fallen

Pub 360, Fruit Production Recommendations > Apples > Apple Calendar > Petal fall (calyx) when most petals have fallen

Excerpt from Publication 360, Fruit Production Recommendations 2010-11,
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Scab
Black Rot
Tentiform Leafminer
Rosy Apple Aphid
Mullein Leaf Bug
Oystershell Scale, San Jose scale
Plum Curculio
European Apple Sawfly
European Red Mite
Blister Spot
Obliquebanded Leafroller
Oriental Fruit Moth
Codling moth
Powdery MIldew
Precautions
Learn more
Other Apple Calendar sections
- Dormant
- Green tip
- Half-inch green to tight cluster
- Tight cluster to pink
- Pink
- Bloom
- Late Bloom/Early Petal Fall
- First summer spray (7-10 days after Calyx)
- Subsequent summer sprays
- Special summer sprays
- Preharvest sprays
- Postharvest treatment
Other Information on Apples
- Apple Growth Stages
- Apple Nutrition
- Guidelines for Protecting Non-Bearing Apple Plantings
- Notes on Apple Diseases
- Thinning and Plant Growth Regulators
- Table 4-7. Products Used on Apples
Chapter 4: Apple Calendar - PDF 357 kb
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Scab (Petal Fall (Calyx) when most petals have fallen)

Resistance to Group 3 and Group 11 fungicides has been confirmed in Ontario. Check the status of these products before using them in your orchard.

Materials: Use one of:
- Manzate Pro-stick @ 6.00 kg/ha or Dithane DG @ 6.00 kg/ha or Penncozeb 75 DF @ see label
- Polyram DF @ 6.00 kg/ha
- Supra Captan 80 WDG @ 3.75 kg or Maestro 80 DF @ 3.75 kg/ha
- Dikar @ 6.75 kg/ha
- Sovran @ 240 g/ha
- Flint 50 WG @ 140 g/ha
- Pristine WG @ 1.0-1.2 kg/ha
Comments: Pristine: Use the higher rate and a shorter interval during periods of rapid growth or when disease pressure is high.

Nova 40 W @ 340 g + Dithane DG @ 3.00 kg/ha
Nova 40 W @ 340 g + Polyram DF @ 3.00 kg/ha
Nova 40 W @ 340 g + Maestro 80 DF @ 1.90 kg/ha
Nustar @ 100 g + Manzate Pro-stick @ 3.00 kg /ha
- Comments: Sovran, Flint, Pristine, Nova, Nustar: Do not use earlier than Tight cluster. See Table 2-11. Fungicide/Bactericide Groupings Based on Sites of Action. After last application of Sovran, Flint, Nova or Nustar tissue is protected from infection for 5-8 days. In conditions of rapid growth, shorten intervals between applications. Check label for details. Do not use Nova, Nustar, Flint, Pristine or Sovran if apple scab is present. Use of these products as eradicants may result in the development of fungicide resistance.
- Comments: Serenade MAX: Provides suppression of apple scab. See Table 2-6. Efficacy Ratings for Pesticides, and notes on Serenade MAX, Bacillus subtilis (Serenade ASO, Serenade MAX).

For more information - Ontario CropIPM: Apple Scab

Black rot (Petal Fall (Calyx) when most petals have fallen)

Materials: Use one of:
- Maestro 80 DF @ 3.75 kg/ha
- Supra Captan 80 WDG @ 3.75 kg/ha
  - Comments: Apply fungicides preventatively to susceptible varieties in orchards with a history of black rot infections. Do not use oil within 14 days of Maestro or Captan
For more information - Ontario CropIPM: Black rot

Tentiform Leafminer (Petal Fall (Calyx) when most petals havefallen)

Apply after egg hatch begins, if there is one more sapfeeding mines per leaf. See Table 11-3. Relative Toxicity of Pesticides to Honeybees. Also see Table 4-10. Thresholds for Tentiform Leafminer on Apples.

Materials: Use one of:

Agri-Mek 1.9% EC @ 750 mL/ha

Comments: Agri-Mek: Do not apply later than 21 days after petal fall. Apply with 10 L of Superior 70 Oil and a minimum of 1,000 L of water per ha. Agri-Mek plus oil may cause russeting to Golden Delicious and other light-skinned cultivars. Do not use Agri-Mek plus oil within 14 days of Captan or Maestro application. Maximum one application Agri-Mek per season. Agri-Mek plus oil is best applied alone. Also controls ERM and TSSM.

Admire 240 F @ 380 mL/ha or Alias 240 SC @ 380 mL/ha

Assail 70 WP @ 80 g/ha

Actara 25 WG @ 315 g/ha

Comments: Actara: Highly toxic to bees exposed to direct treatment or to residues on blooming crops and weeds. Do not apply during bloom, and wait at least 5 days after treatment before placing beehives in or near treated fields. Maximum four neonicotinoid applications per season.

Calypso 480 EC @ 145 mL/ha

Comments: Admire/Alias, Assail, Actara, Calypso: Apply neonicotinoid insecticides when population is mainly in the sap feeder stage. These products are in the same chemical family and should not be used in rotation. These products will also control other insects at this timing. Note that some neonicotinoids are toxic to bees.

Altacor @ 215 g/ha

Delegate WG @ 420 g/ha or Perm-Up @ 520 mL/ha or Ambush 500 EC @ 400 mL/ha

Comments: Altacor, Delegate: Apply when population is mainly in the sapfeeder stage.

Pounce @ 520 mL/ha

Decis 5 EC @ 250 mL/ha

Ripcord 400 EC @ 250 mL/ha or Up-Cyde 2.5 EC @ 400 mL/ha

Matador 120 EC @ 83 mL/ha or Silencer 120 EC @ 83 mL/ha

Comments: *Pyrethroids (Pounce, Ambush, Perm-up, Ripcord, Up-Cyde, Decis, Matador, Silencer): Pyrethroids are highly toxic to beneficial insects, and may lead to outbreaks of European red mite. In years where leafminer egg hatch is delayed, a pyrethroid can be applied at petal fall when first sap-feeding mine is detected. This treatment also controls tarnished plant bug and spring feeding caterpillars. Maximum one pyrethroid application per season.

Rosy apple aphid (Petal Fall (Calyx) when most petals have fallen)

Spray if 20 or more clusters in a 100-cluster sample are infested.

Materials: Use one of:

Admire 240 F @ 230 mL/ha or Alias 240 SC @ 230 mL/ha

Assail 70 WP @ 120 g/ha

Actara 25 WG @ 160 g/ha

Comments: Admire, Alias, Assail, Actara (neonicotinoids): Some neonicotinoids are toxic to bees. Repeated use may result in mite outbreaks. Use a maximum of two applications per season.

Comments: Actara: Highly toxic to bees exposed to direct treatment or to residues on blooming crops and weeds. Do not apply during bloom, and wait at least 5 days after treatment before placing beehives in or near treated fields.

Movento 240 SC @ 2.0 L/ha

Comments: Movento: Has slow activity; control may not be apparent for 2-3 weeks. Under high pressure a second application may be necessary 2 weeks later. See the Movento label for additional details. Do not tank-mix with sulfur.

Zolone Flo @ 2.00 L/ha

For more information - Ontario CropIPM: Rosy apple aphid

Mullein leaf bug (Petal Fall (Calyx) when most petals have fallen)

Apply controls where 7-9 nymphs are caught per 25 taps.

Materials: Use one of:
- Calypso 480 EC @ 290 mL/ha
- Actara 25 WG @ 315 g/ha
- Admire 240 F @ 380 mL/ha or Alias 240 SC @ 380 mL/ha
  - Comments: Admire, Alias, Assail, Actara (neonicotinoids): Note that some neonicotinoids are toxic to bees. Repeated use of some neonicotinoids may result in mite outbreaks. Use a maximum of two neonicotinoid applications per season.
- Diazinon 50 W @ 3.25 kg/ha
- Comments: Diazinon: Very toxic to bees and some beneficial insects.
For more information - Ontario CropIPM: Mullein leaf bug

Oystershell scale and San Jose scale (Petal Fall (Calyx) when mostpetals have fallen)

Apply when the crawlers are active in orchards with a history of scale.

Materials: Use one of:
- Guthion 50 WSB @ see label or Sniper @ see label
- Movento 240 SC @ 365 mL/ha
For more information - Ontario CropIPM: Oystershell scale, San Jose scale

Plum curculio (Petal Fall (Calyx) when most petals have fallen)

Materials: Use one of:
- Actara 25 WG @ 385 g/ha
  - Comments: Actara: Highly toxic to bees exposed to direct treatment or to residues on blooming crops and weeds. Do not apply during bloom, and wait at least 5 days after treatment before placing beehives in or near treated orchards.
- Calypso 440 EC @ 440 mL/ha
  - Comments: Actara, Calypso: Optimal timing is at petal fall plus 3 days. However if monitoring indicates plum curculio is in the orchard prior to this timing, then insecticides should be applied at petal fall. Do not use Calypso/Actara in border sprays. Note that some neonicotinoids are toxic to bees. Repeated use of some neonicotinoids may result in mite outbreaks. Use a maximum of two neonicotinoid applications per season.
- Imidan 50 WP @ 3.75 kg/ha
- Zolone Flo @ 3.00 L/ha
- Guthion 50 WSB @ see label or Sniper @ see label
  - Comments: Guthion, Sniper, Imidan, and Zolone: Apply immediately at petal fall, or when monitoring indicates plum curculio is in the orchard.
- Surround WP @ 50.0 kg/ha
  - Comments: Surround: Must be applied before plum curculio is present in orchard. Make two applications, 7 days apart, at 50 kg/ha, to establish a base layer. Continue at 7-14 day intervals, using a reduced rate of 25 kg/ha, to maintain even coverage of developing fruits. Do not use Surround in border sprays. See notes on Kaolin Clay (Surround WP).
For more information - Ontario CropIPM: Plum curculio

European apple sawfly (Petal Fall (Calyx) when most petalshave fallen)

Apply where there has been a history of damage. Use yellow sticky traps to monitor for sawfly adults. If a prebloom insecticide has been applied, spray postbloom when six sawflies have been caught per trap. Where no prebloom insecticides have been applied, spray postbloom when three sawflies have been caught per trap.

Materials: Use one of:
- Guthion 50 WSB @ see label or Sniper @ see label
For more information - Ontario CropIPM: European apple sawfly

European red mite (Petal Fall (Calyx) when most petals have fallen)

Thorough spray coverage is essential for good control with miticides. See Table 4-9. Activity of Miticides Registered on Apple and/or Pear in Ontario. Miticides are best applied alone. Do not apply any miticide more than once per season. To prevent development of pesticide resistance, rotate products from different groups. See Strategies for managing resistance to insecticides.

Materials: Use one of:

Agri-Mek 1.9% EC @ 750 mL/ha

Comments: Agri-Mek: Apply when there are 5-7 active mites/leaf timed for 50% egg hatch, no later than 21 days after petal fall. Apply with 10 L Superior 70 Oil and a minimum of 1,000 L of water per ha. Agri-Mek plus oil may cause russeting on Golden Delicious and other light-skinned varieties. Do not use Agri-Mek plus oil within 14 days of a Captan or Maestro application. Alternate yearly with other early season miticides (e.g., Superior 70 Oil, Apollo).

Acramite 50 WS @ 851 g/ha or 3.75 pouches/ha

Envidor 240 SC @ 750 mL/ha

Comments: Agri-Mek and Envidor: Also control apple rust mites.

Comments: Envidor: Has slow activity and results may not be apparent for up to 1 week.

Kanemite 15 SC @ 2.1 L/ha

Comments: Acramite, Envidor and Kanemite: Apply when there are five or more active mites per leaf.

Apollo SC @ 300 mL/ha

Comments: Apollo: Kills mite eggs. Apply when mites are mostly in the egg stage and before there are more than three active mites per leaf. Apply Apollo alone in a minimum of 1,100 L of water per ha.

Carzol SP @ 1.10 kg/ha

Comments: Carzol: Harsh on beneficial insects, mites and bees.

For more information - Ontario CropIPM: European red mite

Blister Spot (Petal Fall (Calyx) when most petals have fallen)

Materials: Aliette WDG @ 2.00 kg/ha

Comments: Apply preventatively to susceptible varieties such as Mutsu and Golden Delicious. Begin applications at petal fall with 1-2 subsequent sprays at 7 day intervals. Do not mix with copper compounds.

For more information - Ontario CropIPM: Blister Spot

Obliquebanded leafroller (Petal Fall (Calyx) whenmost petals have fallen)

For overwintering obliquebanded leafroller, apply at petal fall. Spray in orchards with historical pest problems or high pest pressure (1-2% of the terminals or buds have larvae or damage). OBLR are resistant to organophosphate insecticides in most commercial apple orchards. Cross-resistance to pyrethroids, Confirm and Intrepid is possible. Avoid treating sequential generations with products from the same chemical group. See Strategies for managing resistance to insecticides. Place pheromone traps in orchards at petal fall to monitor OBLR adults.

Materials: Use one of:

Success 480 SC @ 182 mL/ha

Entrust 80 W @ 109 g/ha

Delegate WG @ 420 g/ha

Dipel 2X DF @ 1.12 kg/ha or Foray 48BA @ 2.80 L/ha or Bioprotect CAF @ 4.00 L/ha

Comments: Dipel, Foray, Bioprotec (B.t. products): Make two applications at 5-7 day intervals if activity of the larvae is extended. For best results when using B.t. products, acidify spray mix to below pH 7.0 and apply at dusk or on overcast days. See Biopesticides and reduced risk products for insect control.

Intrepid 240 F @ 750 mL/ha

Confirm 240 F @ 1.00 L/ha

Altacor @ 215 g/ha

For more information - Ontario CropIPM: Obliquebanded leafroller

Oriental fruit moth (Petal Fall (Calyx) when most petals have fallen)

This is a special spray for orchards where there is a history of damage or pressure. Timing is critical for effective control; use monitoring results to adjust spray timing. Apply insecticides 6-10 days after upswing in pheromone trap catches, which often coincides with petal fall. Alternatively, use this degree-day model to time the application of insecticides for OFM. Begin accumulating degree days (base 7.2° C) at first sustained moth catch (biofix). Apply insecticides targeting first generation larvae. If an insecticide is used at this time to manage OFM the application of mating disruption products may be delayed until mid-June.

Materials: Use one of:

Intrepid 240 F @ 1.00 L/ha

Comments: Intrepid: Apply at 139-153 DDC for hatching eggs and young larvae.

Assail 70 WP @ 240 g/ha

Calypso 480 EC @ 440 mL/ha

Comments: Assail, Calypso: Apply at 139-153 DDC for eggs or larvae. Repeated use of some neonicotinoids may result in mite outbreaks. Use a maximum of two products in this group per season.

Rimon 10 EC @ 1.4 L/1,000 L

Comments: Rimon: Apply at 111-139 DDC. Use for first generation only. See notes for codling moth.

Altacor @ 215 g/ha

Delegate WG @ 420 g/ha

Comments: Delegate, Altacor: Apply at 194-208 DDC or earlier if using as an ovi-larvicide.

Decis 5 EC @ 250 mL/ha

Comments: Decis: Apply Decis at 194-208 DDC or earlier. See Degree-day modeling and determining a biofix. Highly toxic to beneficial insects and may lead to outbreaks of European red mite. Use only as a last resort. Use a maximum of 1 application per season.

For more information - Ontario CropIPM: Oriental fruit moth

Codling moth (Petal Fall (Calyx) when most petals have fallen)

Materials: Rimon 10 EC - 1.4 L/1,000L
- Comments: Has a unique mode of action and should be applied earlier than other products for codling moth. Apply Rimon at petal fall and re-apply 10-14 days later. Use for first generation only. See label for additional information on rates and volumes. Do not allow Rimon to drift onto grapes as leaf spotting may occur. The application of Rimon at this time will provide subsequent control of OBLR and OFM.
For more information - Ontario CropIPM: Codling moth

Powdery mildew (Petal Fall (Calyx) when most petals have fallen)

If powdery mildew was a problem in previous years, then an application of a fungicide is necessary at this time. Spray susceptible varieties. If powdery mildew was prevalent the previous year, apply fungicides beginning at Green tip. Otherwise, begin application at Tight cluster and continue to First summer spray. Additional sprays beyond First summer spray may be needed on susceptible varieties or if disease pressure is severe.

Materials: Use one of:

Nova 40 W @ 340 g/ha

Nustar @ 200 g/ha

Comments: Nova, Nustar: These products do not control scab and should be tank-mixed with a protectant fungicide. See options for apple scab control at Half-inch green to tight cluster.

Sovran @ 240 g/ha

Flint 50 WG @ 140-210 g/ha

Comments: Flint: For powdery mildew control, use 210 g/ha during pink to bloom stage.

Pristine WG @ 1.0-1.2 kg/ha

Comments: Pristine: Use the higher rate and a shorter interval during periods of rapid growth or when disease pressure is high.

Dikar @ 6.75 kg/ha

Microscopic Sulphur @ see label

Kumulus DF @ 22.5 kg/ha

Comments: Microscopic Sulphur, Kumulus: Do not use on Delicious because these products can cause an increase in red mite and scale insect populations.

Comments: Serenade MAX: Provides suppression of apple scab. See Table 2-6. Efficacy Ratings for Pesticides, and Bacillus subtilis (Serenade ASO, Serenade MAX).

For more information - Ontario CropIPM: Powdery mildew

Precautions

Read the product label and follow all safety precautions.

Consult the product label for suggested water volumes. Otherwise, use enough water to ensure thorough spray coverage. Where the product rate is listed in amount per 1,000 L, and if a water volume is not provided on the label, use enough water to wet the foliage to the near drip point.

For information on identifying pests and monitoring apple orchards, refer to OMAFRA Publication 310, Integrated Pest Management for Apples.

Products are listed according to insecticide and fungicide group. Use products from different groups to prevent the development of pest resistance. For resistance management, refer to Pest Resistance to Insecticides, Fungicides, Miticides.
For preharvest interval, re-entry period, maximum number of applications and chemical group, see Table 4-7. Products Used on Apples.

Learn more:

Notes on Apple Diseases

Pub 360

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