Earwigs

Agronomist, Lindsay Baker (Landmark), reports feeding damage by earwigs in several wheat paddocks around Forbes, in the Central West Slopes and Plains district of New South Wales. Lindsay says the earwigs have chewed directly into recently sown wheat in many paddocks on heavy black soils. The earwigs have typically attacked the germ end of the seed. District agronomist, Rebecca Byrne (NSW I&I), has reported similar damage to cereal crops around Moree, in the North West Slopes and Plains district of New South Wales. Large numbers of earwigs have been observed across the paddocks.

Agronomist, Brad Coleman (Coleman Agriculture), has also reported finding earwigs damaging emerging wheat seedlings around Rowena, in the North West Slopes and Plains district of New South Wales. Again, the damage is very specific; the earwigs are chewing a single hole in the seeds just as the coleoptile emerges. Brad says that this damage, combined with some chewing damage caused by crickets, is resulting in patchy and low plant numbers in several crops in the area.

In all of these instances the species of earwigs causing damage has not been confirmed however based on descriptions it is likely that they are European earwigs (Forficulina auricularia). European earwigs are an introduced species that appear to be spreading in southern agricultural areas, perhaps at least in part due to increased levels of stubble retention. They cause damage by chewing germinating seeds, shredding leaf tips or chewing holes in leaves. Crops that have previously been damaged by European earwigs include canola, cereals and some legume crops.

Control options for European earwigs are limited, and it is important to remember that not all earwig species are pests. For further information about earwigs, refer to PestFacts Issue No. 1.