Gypsy moth outbreak poses risk to Michigan trees

An outbreak of gypsy months, an invasive species in Michigan, is taking its toll on trees in the state.

Watch Paula Tutman's report on the gypsy moth outbreak in the video player above.

Here's more on the gypsy moth: 


  • Gypsy moth caterpillars emerge from tan, fuzzy egg masses in April and feed on leaves through late June.  
  • Caterpillars are hairy, with a yellow and black head and 5 pairs of blue spots, followed by 6 pairs of red spots.
  • Mature caterpillars are 1.5 to 2 inches in length.
  • Leaf debris and small, round frass found under trees are indications of gypsy moth infestation.
  • Male moths’ wings have a wavy pattern of brown to dark-brown and span 1.5 inches.
  • Female moths are larger than males and do not fly.  Wings are white to cream with wavy black markings.

Habitat:  Most often feeds on the leaves of oak and aspen but can also be found on hundreds of other plant species.

Native Range: Europe and Asia

U.S. Distribution: Northeastern U.S. west to Minnesota

Local Concern: Gypsy moth caterpillars defoliate trees, leaving trees vulnerable to diseases and other pests, which may lead to tree mortality.  During large outbreaks, debris and frass from feeding caterpillars can be disruptive to outdoor activities.

Pathways of Spread: Though female moths do not fly, small caterpillars can be blown by the wind to other trees.  Gypsy moth egg masses and pupae can be unknowingly transported on firewood, vehicles and recreational gear.  

About the Authors:

Ken Haddad is the digital content and audience manager for WDIV / He also authors the Morning Report Newsletter and various other newsletters. He's been with WDIV since 2013. He enjoys suffering through Lions games on Sundays in the fall.