I don't have a book reccomendation, but here's a website with lots of info. You could find some information specific to Missouri by doing a Google search on - phenology missouri. I think you'll find that phenology has some interesting horticultural/agricultural applications. It is often used to predict certain insect emergences, etc.

Here is a link that might be useful: Phenology info

There's a book called Coincide by Don Orton that I believe has much of this information.

I'm not sure where you can purchase it, though.