Rhinoceros beetle
A large black beetle with a horn that bores into the crowns of palms, leaving V-shaped cuts in the opened fronds.
Also known as: Coconut rhinoceros beetle
Symptoms and identification
Fronds open with neat V- or wedge-shaped cuts, like they have been snipped with scissors. Holes with chewed fibre appear at the base of young leaves in the crown.
Causes
The beetles breed in rotting logs, manure heaps and compost, and fly to palms to feed on young, unopened leaves.
Organic treatment
Pull beetles out of holes with a hooked wire. Place naphthalene balls or neem cake in the inner leaf axils to deter them.
Prevention
Remove or turn manure pits, compost heaps and dead palm trunks near palms, as these are breeding sites. Fill the top leaf axils with a mix of neem cake and sand two or three times a year.
Chemical treatment (use with care)
Use a product labelled for rhinoceros beetle on palms, following local agricultural advice.