As far as thunderstorms go the only data I have heard of claims New England gets about 0.5 lb N per K per year. The prof who gave this data said a good study for a Masters degree would be to do this in Florida. Florida is the Lightning capital of the USA.
Nitrogen Fixation by legumes is one of the big N sources. As a kid I lived in Penna. and my daddy planted Clover to help keep the lawn green. Do people still do this??? What is a legume and how does it make N ????
You can lead a Donkey to water but you can't make the Jackass Drink
"As Americans you have the right to be stupid." John Kerry
"Life is tough, but it's tougher when you're stupid.” John Wayne.