Turfgrass - May/June Beetle Grubs

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Phyllophaga (May beetle or June beetle) grubs require three years to complete their life cycle. Adult May/June beetles are larger than masked chafers (5/8 to 7/8 inches) and range in color from tan to brown to almost black. Adults emerge from the soil in May and June and fly around lights at night. While adults do not attack turf, they do feed on foliage of a wide range of trees, shrubs, and other plants. Eggs are deposited in the soil and hatch in 3 to 4 weeks. Small grubs feed on grass roots during the first summer, moving down in the soil profile with the onset of cooler fall temperatures. Grubs return to the upper root zone in April or May, actively feed throughout the second growing season, then again move deeper in the soil to overwinter. In the third year, Phyllophaga grubs return to the root zone and feed until May or June, when they enter the pupal stage. Adults develop from the pupae late in the summer, but remain in the soil until the following May or June, which completes their life cycle.



Breaking Entomological News...

  • Insect Science major Earl Agpawa (conducting undergraduate research with Joe Louis and Eileen Hebets) was named the 2020 winner of the ESA’s Plant-Insect Ecosystems Undergraduate Student Achievement Award.This is a national award that recognizes outstanding accomplishments in entomology by an undergraduate student working with insect-plant interactions. Congratulations, Earl!
  • PhD student Sajjan Grover (mentored by Joe Louis) was named the 2020 winner of the ESA’s Plant-Insect Ecosystems Kenneth and Barbara Starks Plant Resistance to Insects Graduate Student Award. This is a national award recognizing a graduate student for outstanding work in the area of host plant resistance. Congratulations, Sajjan!
  • Dr. Joe Louis receives a grant to study resistance in sorghum to fall armyworm
  • Check out the Emerald Ash Borer Resource Center, and our Emerald Ash Borer Look-Alike Insects Sheet - Be Sure Before You Treat!