When I picked up Newcomb's Wildflower Guide
from the library, I didn't have a clue how to identify flowers using a book, and I was afraid I would be in over my head. I shouldn't have been worried: Newcomb's wildflower categorization is easy to pick up on, using readily understood visual cues like the number of petals on a flower, flower color, and leaf type. I was able to identify almost every flower I was trying to name, and I'm as amateur as it gets.
Using this guide is infinitely faster and less frustrating than trying to figure out flower names online, and the illustrations are very well-done and helpful. I do wish more illustrations had been in color, but the black-and-white drawings are still effective.