A Great Lakes Wetland Flora (Second Edition)

What did not fully impress me were the illustrations, which were sometimes misleading (though 90% are very good), and that the key is often depends too much on one feature, which only works if that feature is fully developed and unique from species not listed in the book (not always the case). Other keys do not have this problem as much, though it is always the challenge of keys. This would also leave me wondering when I would key out by elimination based on something genereral, such as, number of stamens, for example. I then find that the picture looks nothing like what I have keyed to. Sometimes, I learn that it's just a bad picture, and other times, I learn that a different species (usually upland) not listed in the book also keys out to the same entry because the key is not specific enough and the picture is too generic to distinguish. But once you do identify the plant, this book shares more useful information about the plant than most other books.

In conjunction with Chadde, we found these books indispensible companions for our aquatic plants class:
Newcomb: Usually better pictures, easy identification (often, simply faster than the traditional keys for initial identification), perfect field size, but not phylogenically organized (important for learning families and identifying related species) or specific to wetlands (sometimes helpful for the facultative species not in Chadde, but not useful for the thousands of wetland sedges and rushes out there).
Crow and Hellquist: Incredible pictures (when present), better key, much more comprehensive (but only in dedicated wetland species--FACW-OBL, very few FAC, FACU, etc.), but too big and expensive for field work.
We also occasionally used Tiner, Peterson's, and some specific Ohio Wildflower books.

Of all the books, though, Chadde has the most wear. That tells me which one is most valuable.