Wintercreeper (Euonymous fortuneii) outcompetes native vegetation where it becomes established and can form dense monocultures. It climbs woody vegetation and can create dense mats which shade out understory vegetation. Its fruit are attractive to birds and seed is easily spread this way.
Wintercreeper is native to China, Korea, and Japan and was introduced into the United States in the early 1900s as ornamental groundcover. It has become naturalized across the eastern U.S.
Wintercreeper is not listed as an invasive species in Illinois.
Wintercreeper has evergreen leaves which can be dark green or have green upper surfaces and purple undersides. Leaves are oppositely arranged on the stem, ovate, and up to 2.5 inches long. They have toothed edges and short petioles (up to 3/8 inch). Young stems are green, stout, and hairless, while older stems become gray with corky bark covered in hairs. Flowers are inconspicuous, with 4 green-yellow petals. Fruits are cream-colored capsules that split open in the fall to reveal a fleshy orange-red seed called an aril.
For more information, explore Management of Invasive Plants and Pests of Illinois.
