Garden weevils are a flightless insect, native to South Africa and currently established in Australia, Norfolk Island and New Zealand, having been introduced in the late nineteenth century. Garden weevils are polyphagous, able to feed on a wide range of plants, however, grapevines are a preferred food, increasing the lifespan and fecundity of adults.
Garden weevils have been reported as being present in vineyards in Hawke’s Bay, Wairarapa and Marlborough and have been present throughout New Zealand for some time, first reported in 1893.
Garden weevils emerge from the soil as adults in Spring and early Summer. Based on industry reports during recent seasons, garden weevil incidence appears to be localised within subregions and ‘hot spots’ of high incidence within blocks. It is not clear why garden weevil damage in vineyards is only now being noticed and exceeding tolerable levels in isolated locations within a few vineyards.
This project investigated the distribution and type of weevil species present in vineyards in three New Zealand winegrowing regions and created resources for the industry to enable identification and increase monitoring.