Hello all!

I have a question for you all. I would like to know more about the certain nector flows in my area (south west washington) but have no idea how to go about it. I would like factual information rathen then asking beekeepers in my local area because I am getting different responces and I am not sure who to listen too.

Is there a book that people use on flowers, etc to help them find out when the nector flow is?