Steel Plates

Asian gypsy moths are not official United States residents. Their home territory is native to Russia, China and Japan. Last year, they hitched a ride on ships coming from Far East Russia loaded with steel plates. They were attracted to the ships by the bright lights used to light up the harbor. Asian gypsy moths love to lay their eggs on smooth flat surfaces, such as the steel plates. Once the ships were loaded with cargo they headed to their destination, Pacific Northwest ports.

The fuzzy brown egg masses arrived here in Portland last spring and some of the intrepid traveling eggs hatched! They found their way into Forest Park and St. Johns and grew up into fully-fledged adults, hoping to make a home for themselves.

An egg mass found on the steel slab during an egg mass search. Photo courtesy of Oregon Department of Agriculture.

The problem with these moths? They love to eat leaves. Lots and lots and lots of leaves. So much they can eat all the leaves off trees in short order, leaving us without the "green" part of Oregon. They also like to travel rapidly. Once they have had a few generations of babies, they can quickly travel to other parts of the state that has yummy, yummy leaves. Trees don't do so well without their leaves!