With the knowledge that there are probably about a million different species of herbaceous plants out there (not to mention their cultivars), I’m looking for a good industry-grade reference specifically for perennials. I’m a big fan of Dirr and Hightshoe for trees and shrubs but have had difficulty finding an equivalent in the single-authored variety. Another key feature would be sketches for use in the field as well.
Any ideas or suggestions?
P.S. Has anyone had any experience with Steven Still’s Manual of Herbaceous Ornamental Plants?