Prévenir et Combattre ce Ravageur

The apple sawfly ( Hoplocampa testudinea ) poses a serious threat to apple orchards in France, especially on organic farms. This pest, which affects fruit growth and production, requires proactive management to limit its damage. This article explores in detail its life cycle, damage, and best practices for controlling this pest, whether using organic or conventional methods.


Life Cycle of the Apple Sawfly

Emergence of Adults

  • Period: Adults appear between April and May, corresponding to the early flowering stage of apple trees (F2-F4).
  • Activity: During this period, females lay around thirty eggs per individual at the base of the flower stamens.

Larval Development

  • Hatching: Eggs hatch after 8 to 18 days.
  • Food: Young larvae feed on the developing apples, causing extensive damage over a period of 3 to 4 weeks.

Diapause

  • Soil migration: Once their larval phase is complete, the larvae leave the fruits to burrow into the soil at a depth of 5 to 10 cm.
  • Duration: They remain in diapause for 9 to 21 months before completing a life cycle of 1 to 2 years.

Damage Caused by Hoplocampe

Visible Signs

  • Circular Holes: These perforations, called "cobbler's punctures," are the direct result of larvae feeding on the fruit.
  • Superficial Galleries: Under the epidermis of the apples, the larvae dig galleries, altering their appearance.
  • Premature Fruit Drop: Affected fruits drop before reaching maturity, resulting in yield losses.

Identification of Larvae

  • Appearance: Yellowish white larvae, measuring between 10 and 15 mm, with a dark brown head.
  • Odor: A characteristic bedbug odor is released when they are crushed.

Infestation Risk Assessment

Adult Trapping

  • Method: White sticky patches attract adults, their color encouraging them to land on them.
  • Intervention threshold: If more than 30 adults are captured per hectare, intervention becomes necessary.

Fruit Tracking

  • After fruit set: Regularly examine the fruit to identify signs of larval attack and assess their intensity.

Hoplocampus Prevention

Soil Management

  • Technique: Work the soil to a depth of 10 cm to disturb diapausing larvae, thus reducing emerging populations.

Promoting Biodiversity

  • Natural Helpers: Attract insectivorous birds by installing nest boxes and promoting diverse hedges in and around orchards.

Close Surveillance

  • Key periods: Inspect trees during flowering and after fruit set for suspicious activity.

Methods of Fighting Hoplocampus

Biological Control

Auxiliaries and Parasitoids

  • Lathrolestes ensator: This parasitoid is an effective natural solution against larvae.
  • Entomopathogenic nematodes: Applied to the soil, they infect and destroy diapausing larvae.

Mass Trapping

  • Device: A large number of sticky plates can capture enough adults to limit spawning.

Quassia Amara Decoction

  • Action: This substance derived from bark acts as a natural repellent, effective at doses of 25 to 30 kg/ha.

Conventional Fighting

  • Insecticide Treatments: Success4 (Spinosad) and Pyrevert (natural Pyrethrum) can be used under specific conditions.
  • Removal of Infested Fruit: Remove damaged fruit before it falls to limit reinfestations.

Economic Impact of Hoplocampe

  • Reduced yields: Premature drop of apples and reduction in saleable production.
  • Deterioration of commercial quality: Deformed or damaged fruits are often unsaleable.

A Commercial Solution for Your Orchards

If your apple trees have suffered losses due to sawfly, it's essential to take swift action to limit future damage. Arboriverse, a specialist in fruit plants, is your partner to help you revive your crops.

Why Choose Arboriverse?

  • Wide Range of Apple Trees: Varieties available in high stem, half stem, cattail, and bare root.
  • Guaranteed Quality: Our plants come from specialized nurseries, ensuring robustness and yield.
  • Competitive Prices: Take advantage of our producer prices to optimize your investments.
  • Fast Delivery: We serve all of France, directly to your orchard.

Tailor-made advice

  • Designing your orchard: Choose the varieties best suited to your region and the pests present.
  • Efficient planting: We provide technical guides for optimal recovery.

FAQs

  • How to detect an early sawfly infestation? Look for the first holes in young fruit during fruit set and use sticky traps.
  • Can sawfly be controlled without insecticides? Yes, thanks to natural aids, plant decoctions, and effective mass trapping.
  • Which plants should you choose after a major infestation? Modern, resistant varieties, available from Arboriverse, offer an excellent solution.
  • Is mass trapping effective on its own? It is useful in addition to preventive measures such as tillage and management of beneficial insects.
  • Can Success4 be used in organic farming? Its use is regulated and requires a specific exemption.

Conclusion

The apple sawfly is a formidable enemy of orchards, but with an integrated strategy combining prevention, monitoring, and appropriate treatments, it is possible to limit its impact. In the event of major losses, Arboriverse is at your side to provide high-quality apple plants and support you in resuming your business. Contact us today to take advantage of our professional solutions and successfully restart your orchard.