Whew, this thread has taken a lot of turns. Evan I split your post off into a new thread so it doesn't get lost.
The "Browse by genus" page is by no means finished or set in stone. I altered it yesterday (or was it this morning) just to demonstrate the flexibility we have here.
We can have the plants all listed with all the accurate and important information, such as the species field, without sacrificing navigation. The big take-away here is that we can make as many different navigation systems as we want.
In fact, we can have a special custom "View all the irises" page that is completely different from any other page. We can have a "Rose finder" page that showcases the roses in whatever format and layout we desire.
The sky is the limit here and I'm absolutely open to making special pages for everything.
