The Red Palm Weevil – an update

Nearly two years ago Yiannis Zithianakis, the agronomist for the Gouves township, first wrote about the Red Palm Weevil (Rhynchophorus ferrugineus) the nasty pest of the palm trees first spotted in Crete in 2005 in trees that had been imported from Egypt.

Since then there has been a massive increase in palm deaths caused by the bug.  

I recently had a very informative meeting with Mr. Yiorgos Hronakis, the agronomist for Malia, during which time we were able to further discuss this serious problem, and where it stands today.

Mr. Hronakis has been very pro-active in his efforts to deal with the problem and recently he hosted his third meeting with local businessmen, hoteliers and interested parties from the other townships to look into ways of dealing with the pest. Present at the meeting were the vice-president of the Iraklion Prefecture and the entomologist of the Benakion Phytopathological Institute in Athens. (A summary of this meeting, as supplied by Mr. Hronakis, appears in our online edition (www.ko-go.gr).  

Following that meeting, it was agreed that collaboration between Prefectures, Ministry Services, Municipalities and Research Institutions must begin without delay so that practical measures can be taken.

During our chat, Mr. Hronakis stated that without substantial financial aid and centralised co-ordination, there is little that our local townships can do to halt the pest on their own.

As discussed at the meeting, we both expressed our concern at the indiscriminate use of powerful chemicals in public places.

Other means of control available are:

Pheromone traps: These have a role to play in controlling the numbers of adult beetles as they search for new homes, but care needs to be taken with these too. If there are no beetles in your area, there soon may be.  Beetles in a kilometre diameter of the trap will be attracted by the scent.

Nematodes: A culture of these tiny organisms is injected into the tree and they search out the "caterpillar" stage of the weevil, which they enter and eat from the inside.

Cultural methods: The adults tend to fly away from their host trees during October/November and May/June looking for new sites and mates. As they are attracted by the scent of fresh wounds, it makes sense not to prune at these times. Also dispose of all cuttings sensibly; the best way to do this is by burning.

Removal: Infested trees that cannot be saved must be removed and destroyed to kill the bugs inside. This is best done by burning.

Transport: One measure already in place is a ban on the movement of palms in infested areas. However, this needs to be enforced, and, some form of compensation needs to be put in place for nurserymen, who have to quarantine their plants.

Only the co-ordinated use of a combination of all of these measures will prove effective.

At this time the weevil seems to have spread as far as Milatos and Vrahasi, and the worry is that it will eventually reach the native palm forest at Vai. Mr. Hronakis said that the small stands of native palm in Stalida have, so far, not been infested. The weevil seems to prefer the canary palm, but as these disappear they will have to change their menu (the weevil actually has a wide range of host plants and it is expected that their next target could be the banana).

To summarise: There are a number of steps that can be taken to control this pest, and to eventually defeat it. However, it will take a centralised, co-ordinated and costly response. It is possible to protect individual palms in gardens but, if you are fighting alone, the moment you stop, the adults will move in from neighbouring areas.