This is a very informative pdf on white flowering spring edibles in Missouri http://mdc4.mdc.mo.gov/Documents/15892.pdf
One that I recognize for sure is the may apple. Very cool looking little plant, and I am learning now that alot of the mushrooms here grow nearby.
A good article with uses, information, and warnings here http://www.best-home-remedies.com/herbal_medicine/herbs/mayapple.htm
good information here too http://davesgarden.com/guides/pf/go/359/
a recipe for may apple jelly http://recipes.chef2chef.net/recipe-archive/44/237097.shtml
I even found a u pick may apple farm here in Missouri-found that interesting http://wildcrops.com/blog/index.php?p=143&more=1&c=1&tb=1&pb=1
Some foods made from May apples are applesauce, drinking or jelly juice, marmalade and pie. The first step for marmalade—and many other recipes—is to make May apple puree. Wash the fruit very well and cut off the black tip and navel. Slice into small pieces and strain through a colander to separate the seeds and peels from the pulp. A good drink is made by combining half May apple and half grape juice. Sweeten to taste, chill and serve. May apples freeze very well and they, no doubt, could be canned if you want to keep some over winter.
Wash ripe mayapples, cut away the stem and blossom ends, and any waste parts. Cut the fruit into pieces and place in a large kettle with water to cover. Bring to a boil, then simmer until mayapples are tender, mashing during cooking. Strain the juice through a cheesecloth or let it drip through a jelly bag. To the strained mayapple juice, add lemon juice and sugar. Bring the mixture to a boil, stirring constantly, then stir in pectin. Again bring to a boil, stirring constantly, and boil hard until the jelly stage is reached.