The Red Palm Weevil 
You may already have read the feature on this pest elsewhere in the paper, and some of you will have read my comments in the online edition of my December column. No apologies from me if I am getting repetitive, as this is an extremely nasty pest. Here is some advise for those of you who have palms in your own garden.
Chemicals
This is a very difficult pest to control and any control measures will have to include the use of pesticides.
Even these, however, do not guarantee success. It is very difficult to spot an infected tree before it is too infested with the bugs to save it.
It is far better to use insecticide application as part of a preventative regime. In Italy and Spain they have been successful in getting on top of the pest by using pesticides.
Because the larvae of the beetle are burrowing away inside the palm it is very difficult, even with a translocated insecticide*, to kill them all with one application. As very few applicat
ions will stay effective for more than four weeks, it is better to carry out repeat applications at one-month intervals. It is also a good idea to use different chemicals to ensure resistance does not build up in the weevil population.
I’m sorry, but if you want to grow palms, and fight the spread of this pest, organic/cultural methods are not enough.
Cultural Methods
The female weevil prefers to lay her eggs wherever the palm is damaged and/or where there is a lot of debris to help to hide her eggs. Cultural method should then aim at reducing these niches.
Palm tree heads soon collect a lot of debris so it is imperative that they are kept as clear as possible. (Whilst doing this job keep your eyes open for evidence of chewed fibres at the leaf bases or weeping, smelly sap – both indicators of the presence of the larvae).
Dead leaves should also be removed regularly. Do not, however, cut them too close to the stem. It is better to cut about 15cm away from the trunk. Spraying the open cuts with a translocated insecticide should kill any females that try to take advantage of this potential entryway into the trunk.
Whilst pruning check that the leaves do not have the tell tale bore holes running through them.
Disposal
Do not dump your prunings or dead trees in the garbage. You will only be aidi
ng the spread of the pest. Why not call your local Dimos and see if they have organised a safe disposal method? Failing this, the recommended way to dispose of infected trees is to bury them covered with lime. Burning is another option but, because palm trunks are so damp, it is very difficult to thoroughly burn and, therefore, kill all the bugs. This picture does not show a palm being wrapped as a gift, but a badly infested tree being wrapped to reduce the risk of weevils escaping before it is removed.
So you still want to grow palms?
Next month I will give advise on what you can do if you still want to grow palm trees.
Reader’s Query
Sheila Hollins has contacted me and asked if I know of any English language books that deal with vegetable growing in this climate. In a word my answer is, unfortunately, no. Can anybody else out there help out? I am sure we all would appreciate such a book. Any queries or tips can be sent to:
*Translocated insecticide – an insecticide that is absorbed by the plant and is transported throughout its system, therefore being effective against pests that are not in contact with the originally sprayed area.
You may already have read the feature on this pest elsewhere in the paper, and some of you will have read my comments in the online edition of my December column. No apologies from me if I am getting repetitive, as this is an extremely nasty pest. Here is some advise for those of you who have palms in your own garden.
Chemicals
This is a very difficult pest to control and any control measures will have to include the use of pesticides.
Even these, however, do not guarantee success. It is very difficult to spot an infected tree before it is too infested with the bugs to save it.
It is far better to use insecticide application as part of a preventative regime. In Italy and Spain they have been successful in getting on top of the pest by using pesticides.
Because the larvae of the beetle are burrowing away inside the palm it is very difficult, even with a translocated insecticide*, to kill them all with one application. As very few applicat
ions will stay effective for more than four weeks, it is better to carry out repeat applications at one-month intervals. It is also a good idea to use different chemicals to ensure resistance does not build up in the weevil population.I’m sorry, but if you want to grow palms, and fight the spread of this pest, organic/cultural methods are not enough.
Cultural Methods
The female weevil prefers to lay her eggs wherever the palm is damaged and/or where there is a lot of debris to help to hide her eggs. Cultural method should then aim at reducing these niches.
Palm tree heads soon collect a lot of debris so it is imperative that they are kept as clear as possible. (Whilst doing this job keep your eyes open for evidence of chewed fibres at the leaf bases or weeping, smelly sap – both indicators of the presence of the larvae).
Dead leaves should also be removed regularly. Do not, however, cut them too close to the stem. It is better to cut about 15cm away from the trunk. Spraying the open cuts with a translocated insecticide should kill any females that try to take advantage of this potential entryway into the trunk.
Whilst pruning check that the leaves do not have the tell tale bore holes running through them.
Disposal
Do not dump your prunings or dead trees in the garbage. You will only be aidi
ng the spread of the pest. Why not call your local Dimos and see if they have organised a safe disposal method? Failing this, the recommended way to dispose of infected trees is to bury them covered with lime. Burning is another option but, because palm trunks are so damp, it is very difficult to thoroughly burn and, therefore, kill all the bugs. This picture does not show a palm being wrapped as a gift, but a badly infested tree being wrapped to reduce the risk of weevils escaping before it is removed.So you still want to grow palms?
Next month I will give advise on what you can do if you still want to grow palm trees.
Reader’s Query
Sheila Hollins has contacted me and asked if I know of any English language books that deal with vegetable growing in this climate. In a word my answer is, unfortunately, no. Can anybody else out there help out? I am sure we all would appreciate such a book. Any queries or tips can be sent to:
*Translocated insecticide – an insecticide that is absorbed by the plant and is transported throughout its system, therefore being effective against pests that are not in contact with the originally sprayed area.
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