Red palm weevil : The red palm weevil (Rhynchophorus ferrugineus) or ferruginous curculionidae is an insect that lives at the expense of palm trees. This insect lives and feeds inside the leaf bases and inside the trunk, making it difficult to detect even by thorough visual inspection.
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- 1 Symptoms and Damage
- 1 Other possible symptoms of red palm weevil
- 2 Control methods
- 1 Indirect
- 2 Direct
- 3 Other means of defense
- 1 Curative treatments
- 2 Startup and destruction of infected palm trees
- 4 Source
Symptoms and Damage
- A palm can be infested by the red palm weevil and not show any symptoms that manifest it for several months, therefore it cannot be ensured that the apparently healthy palm trees in areas of confirmed presence of the insect do not in turn contain the pest . This circumstance causes that it is not possible to have a record of the degree of affection suffered by a palm tree in its tissues at the time of undertaking the preventive or curative treatment of the specimen.
- The damages suffered by the infested specimens are produced by the weevil larvae when feeding inside the palm tree . If the attack occurs by the apex of the palm, it loses the arrow of young leaves, which when pulled easily detach, and the palm dies quickly. This last case occurs very especially in the Canarian palm.
- If the larvae are eating in the upper area of the trunk, the young leaves when growing and going outside show pieces of leaflets and eaten rachis. The leaves oy the tillers can be easily detached when the larvae develop in them, observing in these cases easily galleries made by the larvae and find cocoons, adults and caked remains of fiber.
Other possible symptoms of red palm weevil
- Straw coloration or abnormal appearance of the central leaves
- Presence of leaflets cut like scissors
- External leaves fallen, sign of tear in insertion with the trunk
- Holes with a viscous reddish exudate and strong odor
- Overall plumb appearance of leaf crown
- Presence of fibrous masses, adults or weevil larvae. GALLERIES OF 1-2 cm. EN * Armpits and pruning cuts
In the places where this pest originates, a series of natural enemies are known that, according to the bibliography, are insufficient for its biological control. At a practical level, the following control methods are recommended:
- Avoid all kinds of injuries, since “injured” palms are more prone to attacks. This implies the recommendation not to prune or other cultural practices that may provoke them (deshijado, shaved), in the months of greatest activity of the curculiónido and limit them to the coldest months of the year (from December to February) which will be the least active in the adult.
- It will always be convenient to cover the wounds with some healing or mastic paste and apply an insecticidal treatment to all the handled specimens.
- Avoid making new plantations of Phoenix canariensis and Phoenix dactylifera palms in the “affected areas”,
Preventive treatments. Alternative sprays every 45 days with formulations based on entomopathogenic nematodes that are included in the list of “Other means of plant defense” of the Ministry of Environment and Rural and Marine Affairs , and with chemicals registered in the Official Registry of Products and Material Phytosanitary and authorized for use on palm trees. Check authorization for that use.
Other means of defense
Steinernema carpocapsae (entomopathogenic nematodes).
Carry out a calendar of treatments through injections to the trunk with chemical products registered in the Official Registry of Products and Phytosanitary Material and authorized for use in palm trees, and alternative spraying with an authorized chemical product and entomopathogenic nematodes.
Starting and destroying infected palm trees
In the case of strongly attacked specimens and that any type of treatment is unfeasible, proceed with the removal and destruction of all plant remains. Proper waste management is essential to prevent the pest from spreading more easily. That is why the remains should not be abandoned in uncontrolled landfills .