1. Tall grass Prairie Wildflowers. © 1995. D. Ladd and F. Oberle, Falcon Press, 262 pp.
2. Wildflowers of the Tall grass Prairie. © 1989. S. T. Runkel and D. M. Roosa, Iowa State University Press, Ames, 279 pp.
3. Wildflowers of Iowa Woodlands. © 1979, 1987. S. T. Runkel and A. F. Bull, Iowa State University Press, Ames, 264 pp.
1. The Illustrated Book of Wildflowers and Shrubs [Eastern North America]. © 1993. W. C. Grimm and J. T. Kartesz, Stackpole Books, Revised Edition, 637 pp.
2. A Field Guide to Ecology of Eastern Forests: North America. © 1988. J. C. Kricher and G. Morrison, Houghton Mifflin Company, Boston, 368 pp.
2. Roadside Plants and Flowers: A Traveler's Guide to the Midwest and Great Lakes Area. © 1985. M. S. Edsall, The University of Wisconsin Press, Madison, 143 pp.
3. Wildflowers, Grasses & Other Plants of the Northern Plains and Black Hills. © 1983. T. Van Bruggen, Badlands National History Association, Interior, SD, 3rd
Edition, 96 pp.
1. Wildflowers: A quick Identification Guide to the Wildflowers of North America. © 1987. R. H. Mohlenbrock, Macmillan Publishing Company, New York, 203 pp.
2. Wildflowers of North America: A Guide to Field Identification. © 1984. F. D. Venning and M. C. Saito, Golden Press, New York, 340 pp.
3. Newcombs's Wildflower Guide © 1977. L. Newcomb and G. Morrison, Little, Brown and Company, Boston, 490 pp.
4. A field Guide to Wildflowers: Northeastern and Northcentral North America. © 1968. R. T. Peterson and M. McKenny, Houghton Mifflin Company, Boston, 420 pp.
1. Co tu kvete? © 1996. D. Aichele and M. Golteova- Bechtleova, IKAR, Prague. 430 pp. [Czech translation of "Was bluht denn da?," © 1993, D. Aichele and M. Golte-Bechtle, Franckh-Kosmos, Stuttgart.]
2. Pocket Guide: Wildflowers of Britain and Northern Europe. © 1995. D. Sutton, Larousse, London, 256 pp.
3. Blumen: Bestimmen auf einen Blick. © 1992. M. Lomann, BLV, Munich. 191 pp.
4. Wiessen Blumen. © 1990. W. Lippert, Grafe and Unzer, Munich, 64 pp.
5. Pocket Guide to Irish Wild Flowers. © 1987. R. I. Ross and G. Moore, Apple Tree Press, Belfast, 71 pp.
[These guides contain descriptions of many wildflowers that have been introduced into the U. S. (and Iowa) from Europe in the past, and have now become part of our flora.]
1. Contemporary Plant Systematics. © 1997. D. W. Woodland, Andrews University Press, Berrien Springs, MI, 2nd Edition, 619 pp.
2. The Vascular Plants of Iowa: An Annotated Checklist and Natural History. © 1994. L. J. Eilers and D. M. Roosa, University of Iowa Press, Iowa City. 304 pp.
3. Prairies, Forests, and Wetlands: The Restoration of Natural Landscape Communities in Iowa. © 1992. J. R. Thompson, University of Iowa Press, Iowa City, 139 pp.
4. Flora of the Great Plains. © 1987. T. M. Barkley, R. E. Brooks, E. K. Schofield, Editors, R. L. McGregor, Coordinator, University of Kansas Press, Lawrence: 1392 pp.
5. Vegetation Communities and Flora of Dolliver State Park, Webster County, Iowa. © 1987. C. L. Johnson-Groh, et al., Proceedings of the Iowa Academy of Science [= Journal of the Iowa Academy of Science, since 1992], Volume 94: pp 84-88.
6. Plant Systematics. © 1986. S. B. Jones, Jr., and A. E. Luchsinger, McGraw-Hill Book Co., New York, 2nd Edition, 512 pp.
7. Flora and Phytogeographical History of Ledges State Park, Boone County Iowa. © 1985. C. L. Johnson-Groh and D. R. Farrar. Proceedings of the Iowa Academy of Science [= Journal of the Iowa Academy of Science, since 1992], Volume 92: pp 137-143.
8. An Integrated System of Classification of Flowering Plants. © 1981. A. Cronquist, Columbia University Press, New York, 1262 pp.
9. Atlas of the Flora of the Great Plains. © 1977. T. M. Barkley, Editor, Iowa State University Press, Ames, 600 pp.
10. Guide to the Vascular Flora of Illinois. © 1975. R. H. Mohlenbrock, Southern Illinois University Press, Carbondale, 1st Edition [2nd Edition published in 1986]. 494 pp.
11. The New Britton & Brown Illustrated Flora of the Northeastern United States and Adjacent Canada. © 1952, 1968. H. A. Gleason, Hafner Publishing Company, New York, Volumes 1, 2, and 3, 1732 pp.
12. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. © 1963. H. A. Gleason and A. Cronquist, D. Van Nostrand Company, Inc. Princeton, 810 pp.
13. The Flora of South Central Iowa. © 1958. T. Van Bruggen, Ph. D. Dissertation in Botany, University of Iowa. [From a facsimile produced by University Microfilms, Ann Arbor, Michigan, 1971.], 505 pp.