Observations of three Listera species: Listera cordata, Listera convallarioides and Listera auriculata.

Listera is a genus in Orchidaceae. According to Case (1987), there are approximately 25 species of Listera in the world. Three of these species are known to occur in Michigan: Listera cordata, L. convallarioides, L. auriculata, and the hybrid L. x veltmanii. Each of the orchid species has a pair of sub-opposite, equal appearing leaves growing near the middle of the stem. The inflorescence is an open, multi-flowered raceme composed of relatively small, inconspicuous flowers. Listera flowers have a lower petal that is forked or bilobed at its apex. Flower color ranges from translucent green to purplish tinged, depending on the species and its maturity.http://deepblue.lib.umich.edu/bitstream/2027.42/54438/1/2875.pdfDescription of 2875.pdf : Access restricted to on-site users at the U-M Biological Station