Today’s post is about the Red Palm Weevil as I wanted to bring to your attention to the devastating effect this little critter is having on the palms as it munches its way across the world.
The lack of action in containing the spread of this weevil by some authorities is inexcusable.
I was not aware of the Red Palm Weevil until I attended a talk at our local gardening club. At that point there was no sign of the Red Palm Weevil in our local area but just nine months later it arrived and infested palms are being left to die, untreated thereby allowing the weevils to move on to their next host unchecked.
What is the Red Palm Weevil?
The Red Palm Weevil (Rhynchophorus Ferrugineus) is an orangey brown beetle, about 3cm long, attracted to palms – especially males of the Canary Island Date Palm (Phoenix canariensis ). Originally of South East Asia the Red Palm Weevil was accidentally introduced to countries such as USA, Egypt, Spain, Portugal, Greece, Italy and France to name just a few. Due to the lack of control of the movement of the palms from infested areas, both internationally and nationally, it is now out of control.
The total life cycle takes about 7–12weeks. The adult female lays approximately two to three hundred eggs (like small grains of rice) on: new growth in the crown of the palm; at the base of young leaves; or in open lesions on the plant. The eggs hatch in two to five days into larva which then feed on the soft fibres and terminal buds. The larvae tunnel through the internal tissue of the tree for about a month until pupation when they then leave the tree and form a cocoon built of dry palm fibers in leaf litter at the base of the tree.
What are the signs of infection?
Early detection of infestation of the Red Palm Weevil is difficult as the larvae that damage the palm live inside the stems and base of leaves. Unfortunately, symptoms of infestation, are not visible until it is serious.
Signs of infestation include: leaves of the adult palm crown wilt and die; holes in the leaf bases; chewed fibre at the base of stem or edge of leaves. Apparently, by the time these external symptoms are observed the damage is usually sufficient to kill the tree and if you place your ear against the palm you can hear the lavae munching away!
However, despite the research carried out so far, no safe techniques for early detection of the pest have been devised.
Protecting and treating palms
Contact Insecticides such as Confidor, Diazinon or Vetimec can be applied to the surface to combat eggs and pupae.
Systemic Insecticides such as Imidacloprid or Tiamatoxin is usually applied through a funnel about 5 cm above the infested area of the trunk so it absorbed into the palm tissue
Pheromone traps can also be attached to the palm to capture and kill the Weevil.
Prevention is better than cure – so one suggestion I discovered is to leave the lower fronds of your palms to die naturally before removing. Alternatively, only trim fronds approximately one meter from the base of the crown rather than close to the trunk as biff the palm is injured, because of freshly cut fronds, such as, this can attract the beetles by kairomone, a smell emitted from the tree’s wounds.
Professional advice should be sought for treatment or removal of the infested palm.
The palms most commonly affected are the Canary Palm Phoenix canariensis and the Date Palm Phoenix dactylifera . Weevils can also attack the Washingtonia although, not as common.
More detailed information, pictures, videos and podcasts about the Red Palm Weevil can be found at the Centre for Invasive Species Research, California
Please also see comments below from Dr.C.M.muralidharan.
Do you have palms in your neighbourhood? Have they been infested with the Red Palm Weevil?