Is it legal to grow Marijuana for sale in Mendocino County California, while elsewhere you would be arrested?

Just asking, is there any truth to it is allowed to grow marijuana in Mendocino County California and law enforcement and the county supervisors look the other way as it feeds the local economy and without the revenue from growing POT, the place would go broke overnight should it be stopped? Any truth to this or just more gossip with no basis or hint of truth? A friend told me they show people how to grow marijuana and it makes millionaires out of those that move there and engage in growing it POT for sale and distribution.