Officials at the Ministry of Agriculture are closely monitoring two plant pests, one of which could pose severe problems if it gains a foothold in Barbados.
The Red Palm Weevil, known scientifically as the Rhynchophorus ferrugineus, causes serious damage to a variety of palms, while the Frangipani moth also known as Pseudosphinx tetrio, occasionally attacks the Frangipani tree and plant. Locally, the moth also feeds on Allamanda and Desert Rose.
The Weevil, which has not been discovered in the island as yet, was found in Curacao in 2009. It is considered to be the most damaging insect pest of palms in the world, including coconuts and ornamental palms.
Originating in Southern Asia and Melanesia, the pest has advanced westwards very rapidly since the 1980s. The adult Weevil is typically reddish-brown and cylindrical with a long curved snout.
Entomologist at the Ministry of Agriculture, Ian Gibbs, explained that the Weevil damages the inside of the palm stem or crown by feeding on soft tissues and can often cause severe damage when a large number of them bore into the soft growing parts.
In the case of severe infestation, the inside portion of the trunk is completely eaten and full of rotten fibres. Reddish brown liquid can also be seen oozing from these holes. In young palms, the top withers, while in older palms the top portion of the trunks bends and ultimately breaks. It is very difficult to detect infestation in the initial stage and when advanced, the losses are irreparable.
According to Mr. Gibbs, insecticides were the most common control of the Red Palm Weevil and can be applied as dust or liquid sprays.
Trunk injections or soil applications of systemic insecticides that move inside the palm, poisoning the weevil larvae and adults may also be effective. Good sanitation practices are needed to prevent the Weevil spreading from infested palms. Chipping, burning and burying infested material deeply can reduce the likelihood that the Weevil will emerge and escape from infested palms.
With regard to the Frangipani moth, Mr. Gibbs said the adults were a drab gray colour but the larvae were brightly coloured large caterpillars.
They are velvety black with yellow green rings and a reddish orange head and can grow up to six inches in length. Female moths lay approximately 50 to 100 pale green eggs in clusters on leaves of the tree. The caterpillars often appear in gardens or landscaping and can defoliate Frangipani trees in a few days.
The Entomologist noted that there were three ways to be rid of the moth. "[You] can do nothing, as after the caterpillars have defoliated the plants they will recover and produce new leaves again or you can remove the caterpillars from the tree and destroy them or spray the plants with an insecticide such as Perfekthion which penetrates the leaves so when the caterpillars feed on them, they will be killed," Mr. Gibbs explained.
Further information on these two plant pests may be obtained by contacting the Entomology Section of the Ministry of Agriculture at 434-5103 or 310-2821.