Red palm weevil (Rhynchophorus ferrugineus)

The red palm weevil affects palm trees

Whether you have a palm tree in your garden or if you are a collector of these plants and you live in an area with a warm or temperate climate on the Old Continent, it is important that you know everything about it. Red weevil, one of the most harmful pests we have today.

In its adult phase it is not harmful, but it is when it hatches from the egg and begins to feed on the interior of the palm tree. In fact, unless she is treated at this early stage, she will most likely not survive. How to avoid it?

Origin and characteristics

View of a red palm weevil pupa

Red palm weevil pupa.
Image - Wikimedia / Luigi barraco

Our protagonist is a weevil (a kind of beetle, but with a longer and thinner body) native to tropical Asia, whose scientific name is Rhynchophorus ferrugineus. It measures two to five centimeters and is red, something that makes it unmistakable.

Its life cycle lasts from 130 to 200 days, and is as follows:

  • Oviposition: after mating, the female lays between 300 and 500 eggs in different palm trees, taking advantage of the wounds and / or cracks that these plants may have. The laying is done in the terminal stems as well as in the soft tissue of the bases of the leaves.
  • Larvae: As soon as they are born, they are whitish yellow in color and do not have legs. On their head they have horizontal conical jaws, with which they can excavate galleries from the axils of the leaves to the crown, inside which they will feed voraciously.
    This phase lasts about 95-96 days. When they arrive, their larval development is completed, they build a cocoon 4 to 6 cm long with fibers extracted from the palm tree.
  • Pupa: it is dark red-brown in color, and forms within the cocoon. During this phase the insect undergoes a metamorphosis, which can last between 15 and 30 days.
  • Adult: when it reaches this stage, if there is still plant material with which it can feed, it will remain a few more days in the palm tree, if not, it will go to another, attracted by the smell of other wounded palm trees in search of a mate to mate and start the cycle.

How to differentiate the male red weevil from the female?

They are very similar, but the male is somewhat smaller in size and also has a small strip of hairs on its beak.

Where has it been introduced?

The red weevil has spread to Africa, Europe and America. In the case of Spain, it appeared for the first time in Almuñécar in 1993. From there, it spread to various parts of eastern Andalusia, Murcia and the Valencian Community through palm trees that were imported from Egypt.

In 2005, he arrived at the palm grove of Elche, the largest in all of Europe. And in the Canary Islands he seriously threatened his native species: Phoenix canariensis. Six years later, in 2011, it arrived in Jerez de la Frontera, where it affected more than 200 specimens. In 2014 he reached Badajoz, the Catalan region of Ribera de Ebro, and the Malaga Park, where he killed 16 centenary palm trees.

To date (2019) it has spread throughout practically the entire Iberian Peninsula (except in the coldest areas), as well as in the Canary and Balearic archipelagos, although its spread is being controlled.

What are the symptoms and damage it causes?

Damage caused by the red palm weevil in the Canary Island palm

Image - Wikimedia / Küchenkraut

The symptoms and damages produced by the red weevil attack at the beginning are not very evident; What's more, it is normal for you to think that you have simply gone through a bad time (cold or thirsty for example), or that you are even healthy. But You have to be very attentive, observe it daily, because when the signs are too obvious, the life of the plant hangs by a thread:

  • The palm tree's eye weakens.
  • The central leaf, the one that acts as a guide, is displaced.
  • Presence of small holes -the galleries- at the point of insertion of the leaves.
  • Healthy leaves that hang down, as if someone had cut them in half.
  • Buds appearance, either on the plant itself or around it.
  • Flowering and fruiting at the wrong time (sometimes, when a plant is very bad, it spends its last energy in creating offspring).

Which palm trees does the red palm weevil attack?

To all in general, but has a predilection for those of the genre Phoenix and specifically for the Phoenix canariensis. But if there is not, it will go for the washingtonia, Brahea ... A friend died of a large Pritchardia from this insect, so don't let your guard down.

If we talk about the size, they are usually plants with an adult or semi-adult trunk with a thickness of more than 2cm; It is very, very rare for young women with a greenish trunk to attack them, although they have another potential enemy: the paysandisia).

How is it treated?

Home remedy against red weevil

View of a young Archontophoenix

The best and most effective is prevention. There are many ways to do it:

  • Do not prune in spring or summer (I would even say that it is not a good idea to do it until mid / late autumn if you live in an area with a mild climate, such as the Mediterranean). In addition, only the dry leaves must be removed; if you also take away the green ones, you weaken it.
  • Take the hose or shower and direct the water to the eye of the palm tree: This can only be done in spring and summer, and only if the specimen is young. But it is a way to drown the larvae that may be hatching.
  • Green products: Fortunately, there are more and more natural remedies that help prevent, such as palm tree fungi or endotherapy with emamectin. You have more information about it at this link.
  • Buy healthy specimens: of course. It is enough that one has a weevil for others to get sick too, and fast.
  • Consciously review the plants purchased via the Internet: if you are one of those who buy in online stores or individuals, when you receive them, examine them conscientiously. The normal thing is that they are professionals and there are no insects, but just in case.

Treatment against red weevil

Once there are already symptoms, or if you have a sick palm tree a few meters from home and you don't want to risk it, what you have to do is treat it with anti-weevil insecticides. Until now, the most effective substances have turned out to be Chlorpyrifos and Imidacloprid, but as in many cases it is currently necessary to obtain a phytosanitary product handler's license, we will not always find these products available to individuals.

But there are some, like this one from the brand No products found.. It is a 40ml bottle, whose active principle is 50% Fosmet, and which costs 13,16 euros. In addition, it is very important to know that it must be used by following its instructions to the letter, and having previously put on rubber gloves.

The treatment season should last from early spring to early fall.

Does the red weevil bite people?

No. The insect itself does not pose any danger to humans or animals. What we do have to be careful is if, for example, we pass by a palm tree that is sick, because there is a risk that the leaves will fall on someone and that, obviously, would be a problem.

Red palm weevil, a potentially deadly pest for palm trees

I hope you now know how to prevent your palm trees from being affected by this pest.


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  1.   Jorge Antonio Estrada Herrera said

    The Red Weevil plague was very interesting, I managed to see it in my CICA I managed to save it, not so my COCO plants I kill 2 already large ones and my case is that I have many Coco plants and another small CICA that is growing very beautiful and I have fear reaches them. My CICA has fungi. I think it is cochineal. Half of the leaves are super infected. Is it advisable to prune it ??? Thanks

    1.    Monica Sanchez said

      Hello Jorge Antonio.

      First of all, mealybugs are not fungi. It is important to clarify it because the treatment to be applied is not the same as that applied in the case of fungi. Mealybugs are insects that can be removed by hand, but when their population grows to become a serious pest, then they must be treated with specific insecticides. You can also use diatomaceous earth.

      The red weevil is another insect, requiring several annual treatments with Chlorpyrifos and Imidacloprid. These insecticides do not have to be mixed: one month is used, and the following month the other.

      Regards!