Last year, I wanted to visit lawns and lots of rural gravel parking lots to document all of the diminutive spring wildflowers that exist under the pressure of car tires and lawnmowers. In Malden, for example, an uncommon bluet exists in a lawn in a city park and isn't encountered in intact natural communities down there. In an accreted gravel pile, formed out of disturbance, I found what I think is Draba verna, pictured, which is more commonly seen in yards than in native settings. I didn't make my catalog for this year, but urge you to check out lawns in the Ozarks for a great diversity of some of the earliest blooming Missouri spring wildflowers. And you won't find them in spring wildflower guides.
Of course, visiting woodlands, even really lousy bottomlands with doghair stands of boxelders and cool season pasture grass, you should find fantastic spring ephemeral wildflower viewing in the next few weeks. While I normally promote visiting high quality native systems, managed with fire and without logging and grazing pressure, spring wildflowers grow even in degraded sites. Try to avoid woods with scraped soil from ATV traffic and logging equipment, obviously, but the smallest patch of intact woods should produce some of the more common spring wildflowers (and morels a little later). And it's in the bottoms, areas that by July are chocked full of impenetrable stands of stinging nettle, where you'll find the bluebell displays which should begin in the Central Ozarks in the next couple of weeks.
In 2009 and 2011, I scanned in the lovely Paul Nelson spring wildflower illustrations from a now out-of-print wildflower guide. See the post here with some illustrations and follow the link in that post to see the rest of the book. Every year, I have to refresh my brain on the differences between the Anemone and False Rue Anemone. So, the refresher course!