Do you have a problem with grubs and Japanese beetles? Courtesy of Bayer Advanced, this life cycle chart provides a visual representation of the white grub and Japanese beetle life cycles, and information on how and when to treat the problem to achieve optimum results and protect turf throughout the year.
The immature stage of the Japaneses beetle - the white grub - typically has a three year life cycle. However, most of the damage to ornamentals and turf grass happens during the spring and fall the second year, when grubs are present in the top inch of the root zone, heavily feeding on grass roots and thatch. In the third year of the cycle, the grubs rise out of the soil as Japanese beetles. These beetles feed on surrounding plants and lay eggs in the soil throughout the summer. These eggs eventually hatch into grubs and the cycle beings again.
Stage 1 Dormant Grub: October – March.
Grubs burrow deep into the soil and rest through the winter. Some move as much as 12 inches below the surface. Come March lawns already under attack by grubs are best treated in early spring or fall. Apply Bayer Advanced 24 Hour Grub Killer Plus for fast results. Grubs will usually stop feeding and start to die within 24 hours.
Stage 2 Feeding Grub: March – April.
Grubs rise from their winter rest and begin feeding on roots, causing extensive damage to turf grasses. Bayer Advanced 12 Month Tree & Shrub Insect Control OR All-in-One Rose & Flower Care are best. The best way to control adult beetles is to make a reemptive strike, in the spring, well in advance of the adults emerging. 
Stage 3 Pupa: April – June.
After this spring feeding period during the third summer of its life cycle, the grub pupates and turns into an adult Japanese beetle. Remember that Bayer Advanced Season Long Grub Control is great to use all season. Grubs are easiest to control when they are young, so take preventative action in late spring through early summer. 
Stage 4 Adult: June – August.
Adult Japanese beetles emerge from the soil and begin feeding on many types of plants and ornamentals, leaving skeletonized leaves. Starting in June try Bayer Advanced Dual Action Rose & Flower Insect Killer. If you haven’t made such a preemptive strike and the beetles are feeding, products that kill on contact and provide systemic protection are most effective.
Stage 5 Egg: July – September.
The adult beetle continues to feed, mate and lay eggs in the soil and turf until up to 60 eggs are laid. It is best starting in August to bring back out the Bayer Advanced 24 Hour Grub Killer Plus. Lawns already under attack by grubs are best treated in early fall. Apply Bayer Advanced 24 Hour Grub Killer Plus for fast results. 
Stage 5 Feeding Larva: August – October.
The eggs hatch into grubs, which feed heavily on grass roots throughout the late summer and early fall, causing extensive damage. Remember that the Bayer Advanced Season Long Grub Control is good for all season use. Grubs are easiest to control when they are young, so take preventative action.
