Basic Literature:


Rhoads, A. F. & Klein, W. M. (1993): Vascular Flora of Pennsylvania: Annotated Checklist and Atlas (Memoirs of the American Philosophical Society). 636 p. [out of print]


Rhoads, A. F. & Block, T. A. (2000): The Plants of Pennsylvania: An Illustrated Manual. - 1061 p. University of Pennsylvania Press. [out of print, new edition in preparation]


Rhoads, A. F. & Block, T. A. (2004): Trees of Pennsylvania: A Complete Reference Guide. - 407 p. University of Pennsylvania Press.



The most recommended field guides:


Newcomb, L. (1989): Newcombs Wildflower Guide. 13th ed., 490 p.


Clemants, S. & Gracie, C. (2006): Wildflowers in the Field and Forest: A Field Guide to the Northeastern United States (Jeffrey Glassberg Field Guide Series). Oxford University Press, 480 p.


Petrides, G. A. (1998): A Field Guide to Eastern Trees. (Peterson Field Guides). 2nd ed., 441 p.





Pennsylvania Flora Project website


Flora of North America


Flora of North America website


PLANTS database for all of North America


Connecticut Wildflower Society (picture gallery)


Wildflowers of Western Pennsylvania


Delaware Wildflowers