Yes, a person working on a marijuana grow can be prosecuted for participating in cultivating marijuana for sale. The person can be prosecuted in both state and federal court and receive a substantial amount of prison time as a consequence. These laws are not likely to change anytime soon, even if Prop 19 is passed. As for the wisdom of participating in a criminal enterprise, getting involved with sophisticated, and potentially violent, criminals is never a good idea.
Yes anyone working on a farm can be prosecuted for illegal cultivation, possession with intent to sell, conspiracy, and/or maintaining a place for the storage of narcotics. These charges are all felonies with a max 3 years in state prison commitment.
The political climate has made the police more aware of the issue, more vocal against it and they have dug their heals into the ground with regards to marijuana. Most police believe marijuana is an illicit controlled substance and treat it the same as heroin or meth.
I have represented many Marijuana defendants with cases in Northern California and even the trimmers get busted and look at some sort of jail time. No farm pays enough based on the risk of getting busted and the potential jail time, probation and cost of an attorney.