Pests

Palm Tree Red Weevil

Scientific name: Rhynchophorus ferrugineus
Affected plant: Principally Phoenix canariensis, although it may also affect specimens of Phoenix dactylifera and, more sporadically species from the genre Washingtonia

---

El weevil is a coleopteran from the curculionidae family, originally from the South-East of Asia and Polynesia; it has spread continuously over other areas of temperate climate. In the year 1995 it appeared from the very first time in the Spanish territory, in the provinces of Granada and Málaga; later, in 2004, it was detected in Valencia autonomous region.
But it was in 2005 when a large spread of the pest took place, as it was detected in the three provinces of Valencia and, for the first time in Catalonia, concretely in the municipality of El Vendrell (Baix Penedès).

The size of an adult is from 2 to 5 cm, it is of a reddish brown colour and presents a very characteristic long beak; the male can be told apart from the female by a small hairy crest that the male has on the beak.

Eggs have an oval shape and are brightly white. Females lay from 300 to 400 eggs in the soft tissue of the crown and in the wounds of the stipes.
The larvae develop inside the palm and may be over 5 cm long at the end of their development. They are apode, piriformis, yellowish in colour and with an encephalic capsule of dark bright brown colour. It is endowed with strong jaws.
The pupa is also yellowish and is protected by a cylindrical cocoon of 4 to 6 cm in size, which the larva makes with fibres that it kneads from the palm tree itself.

The complete cycle from egg to adult lasts from 3 to 4 months. Adults do not usually leave the palm until it is totally destroyed. They may bear several generations within the same specimen of palm, where they live all the phases of the insect gregariously. When adults leave the stipe of the palm, they carry out flights to colonize others, preferably those with wounds, be them accidental or provoked by the pruning.
It is extremely difficult to detect the presence of the pest when it begins its attacks. The most evident symptoms are usually detected 12 to 24 months after its infestation; they usually manifest by an asymmetry in the crown, wilting of the leaves and weakness of the eye. The affected leaves can be easily pulled off and in its insertion point, the dug galleries can be observed, as well as the presence of cocoons. Later, the whole crown of the palm tree becomes affected, which causes its death.

This pest can be confronted with Endoterapia Vegetal; by applying two annual treatments, one in spring and the other in late summer, the palm tree becomes immune to new attacks.