Seldom-seen weevil emerges in Far North

The current pre-Christmas weather conditions are right for the re-emergence of a little-seen, lawn-devouring South American weevil in the Far North, a Northland-based insect expert says.

Cable Bay, Northland-based entomologist Dr Jenny Dymock, who works with the Northland Regional Council, says the recent weather has been ideal for an outbreak of the turf grass weevil (Sphenophorus brunnipennis).

Dr Dymock says the insect was first discovered in New Zealand in the late 1920s and is also found in Australia.

Although it is not often seen in Northland, she has recently received reports of the insect damaging lawns at Poutu and Fairburn in the Far North.

“I last saw this damage in December 1999 in Doubtless Bay and Kaitaia.”

Dr Dymock says while she finds the occasional adult weevil (about 7mm long) while searching for another pest, the Tropical Grass Webworm, she has never seen weevil damage to pasture kikuyu.

Lawns however are a different story, with the weevil laying its eggs at the base of short, mown kikuyu.

“The tiny white legless grubs (which many people mistake for eggs) then feed at the base of the kikuyu and grow to about 9-10mm.”

Dead patches then appear on lawns and the grass can be pulled out in tufts.

Dr Dymock says lawns usually recover but if people want to spray to control the weevil, a general purpose garden insecticide should do the trick.

Dr Dymock says advice about a range of insect and other pests is available from the regional council’s website via: www.nrc.govt.nz/nasties  Biosecurity officers can also be contacted via the council’s freephone (0800) 002 004.