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Photo by: Gary Fewless

Location: UW-Green Bay

Date taken: April 24, 2001

Yellow Trout Lily (Erythronium americanum)


Yellow Trout Lily (Erythronium americanum) is also known as Adder's Tongue, Dog-tooth Violet, Fawn Lily. The mottled leaves resemble spots of a fawn or a trout, as reflected in some of the common names. The name "Dog-tooth Violet" is unfortunate, because this species is not even closely related to the Violets.

Yellow Trout Lily is a member of the group of plants known as spring ephemerals. They grow in deciduous forests and share a general style of life history in which they must grow early in the spring to get sufficient sunlight before the tree canopy develops leaves and severely reduces the light levels for the summer. Many spring ephemeral species then go dormant during the summer.

A similar species, White Trout Lily (Erythronium albidum) also grows in our area. The leaves of the two species are indistinguishable. Both species are clonal, forming large populations under good conditions. Young plants or those more heavily shaded may develop only one leaf and will not flower in that year. More robust plants (ramets) capable of flowering will develop two leaves.

Yellow Trout Lily is distributed across much of the eastern United States. In Wisconsin it is most abundant in the area of Brown, southern Oconto, Manitowoc, Kewaunee and Door counties and in the Stevens Point/Wausau area.

  • Contributed by Cofrin Arboretum Botanist Gary Fewless

© 2001-2004 The Cofrin Center for Biodiversity and the University of Wisconsin Green Bay, All Rights Reserved
Last updated on April 15, 2014