Downy Yellow Violet (Viola pubescens) growing on a wooded hillside at Geode State Park in Henry county, Iowa.

Details: 

Canon EOS 10D,  shutter 1/180 second, aperture f11, ISO 100, Canon EF 100 mm macro lens, Canon MR-14EX ring flash.

Selected References:

Thieret John W, Niering William A, and Olmstead Nancy C. National Audubon Society Field Guide to North American Wildflowers, Eastern Region. New York: Alfred A. Knopf, Inc. Plate 301, P 821.

USDA-NRCS. "Plant profile for Viola pubescens"  The PLANTS Database (http://plants.usda.gov/ ). National Plant Data Center, Baton Rouge, LA 70874-4490 USA. 2004. < http://plants.usda.gov/cgi_bin/topics.cgi?earl=plant_profile.cgi&symbol=VIPU3 > (19 Apr. 2005).