Australian lawn beetle

Taxonomic position: Sericesthis geminata belongs to the order Coleoptera and the family Scarabaeidae. It is widely recognized as a serious soil-dwelling pest in Australia, commonly referred to as part of the "white grub" complex that causes significant degradation of turf and pastures.

Affected crops: This pest primarily targets turfgrasses, including lawns, golf courses, sports fields, and various pasture grasses. By feeding on the root systems, they reduce the plant's ability to absorb water and nutrients, leading to rapid decline during dry periods.

Biology and life cycle: The species typically completes one generation per year. Adult beetles emerge in late spring or summer to mate and lay eggs in moist soil. The larval stage is the most destructive phase, consisting of three instars that spend their time underground feeding voraciously on roots before reaching the pupal stage.

Nature of damage and pest status: The damage is characterized by circular or irregular patches of dying or browned turf. Because the roots are severed, the turf layer becomes loose and can often be rolled back like a carpet. Secondary damage is frequently caused by birds, bandicoots, and other predators digging through the turf to feed on the grubs.

Protection measures: Management strategies emphasize integrated pest management (IPM). This includes monitoring soil populations to determine treatment thresholds, applying entomopathogenic nematodes to target larvae biologically, and using registered soil insecticides when necessary. Improving turf health through proper irrigation and aeration can also help mitigate the impact of infestation.