Oregon’s attorney general has approved language for a ballot measure to make psychedelic mushrooms legal.

The measure would reduce criminal penalties for the manufacture, delivery and possession of psilocybin — the hallucinogen contained in psychedelic mushrooms.

In a tweet, the Oregon Psilocybin Society said it will start gathering the 140,000 necessary signatures in December, to get the measure onto the ballot in 2020.

The number of signatures required is nearly equal to the population of Salem.

On its website, the society says there’s a growing body of evidence the drug is safe and effective to treat things like depression, anxiety, PTSD and, ironically, drug addiction.

Oregon has a history with mushrooms. The author and Eugene counterculture figure Ken Kesey participated in government studies of hallucinogens in the 1960s.

Psychedelic mushrooms are seen in a grow room at the Procare farm in Hazerswoude, central Netherlands on this Aug. 3, 2007 file photo.

Psychedelic mushrooms are seen in a grow room at the Procare farm in Hazerswoude, central Netherlands on this Aug. 3, 2007 file photo.

Peter Dejong/AP

The federal government controlled use of mushrooms in the 1970s.

A spokeswoman for Oregon’s top prosecutor, Attorney General Ellen Rosenblum, said the agency doesn’t typically comment on ballot measures.

A similar effort to legalize in California failed recently.