A little into Who Named the Daisy? Who Named the Rose?: A Roving Dictionary of North American Wildflowers and you'll find that it is impossible to put down!
One of the most entertaining botany books I've ever read. The author loosely applies the label "North American Wildflower" to all blossoms now running free. Many were brought over by early European settlers and the plants quickly jumped out of the garden and into the wild. Author lists literary descriptions for each plant (some funny and bawdy!)