We captured the first Japanese beetle adults of the year last week in our traps on the Purdue Campus. These traps are located in an area where emergence tends to take place much earlier than at most locations, so don’t expect to see any significant wide-scale emergence for another 2-3 weeks. We monitor this particular site in order to be able to provide turf and landscape managers with an early heads-up so they can prepare as necessary. For turfgrass managers concerned about controlling the larvae (white grubs) of this insect, the chart below provides guidance on product selection and timing in relation to expected efficacy.
Turfgrass Entomologist