Beetles are semi dormant in your soil in winter, just like our lawns. The damage to your lawn generally won’t occur this time of year, but it is important to understand their lifecycle and signs of infestation, so that you can take prompt action when they become active. Being aware of what’s under the soil will keep you one step ahead of the game and better equipped to deal with these uninvited guests.
Root feeding grubs are sometimes known as white curl grub, scarab beetle larvae, lawn beetle larvae or cockchafer. These are the common names for the juvenile stage of lawn beetle that feed on the lawn roots. White curl grub, however, is sometimes incorrectly referred to as a ‘witchetty grub’.
These beetles – adult lawn grub – feed on the roots and can be a serious problem for some lawns. Cool season varieties like fescue and warm season varieties like kikuyu and couch can experience major damage from a nasty infestation, but they are not usually an issue for buffalo varieties. Stressed, under-nourished lawns are also particularly prone to damage.
Adult beetles are black and shiny, about 15mm long with brown serrated legs. The eggs are laid in Spring and early summer, developing into larvae that then feed on the roots. The pupal stage causes no damage, but the emerging grubs in late spring/early summer do. The beetles are dormant or semi dormant in winter.
A small infestation of black beetle can provide benefits to some lawns, for instance buffalo grass varieties help the soil with tunnelling activity and stimulating new root growth, but if you see damage, it’s best to send them packing.
Check out the Lawn Solutions Australia lawn care page for more helpful tips and advice here.