A good guide, but if you are serious and only need one field guide, own Newcomb's. ( )

All the flowers you're most likely to encounter in the eastern and north-central US, westward to the Dakotas and southward to North Carolina and Arkansas, as well as the adjacent parts of Canada. Flowers arranged by color and plant characteristics. Includes 1,293 species in 84 families, all described and illustrated. An excellent and very useful field guide, although I would have liked more colored illustrations. ( )