The Oakland City Council’s public safety committee approved a resolution Tuesday to decriminalize certain natural psychedelics, including mushrooms, paving the way for Oakland to become the second city in the country to do so.

The resolution, introduced by committee chairman Noel Gallo, instructs law enforcement to stop investigating and prosecuting people using the drugs. It applies to psychedelics that come from plants or fungi, not synthetic drugs like LSD or MDMA, also known as ecstasy. The measure next heads to the City Council for deliberation.

It was approved by three committee members. One committee member, Loren Taylor, abstained.

Though there are rarely any arrests in Oakland over the use of psychedelic plants, Gallo said the resolution is a step toward legitimizing use of the plants for medicinal purposes.

“We want to be able to tell our police department we have other priorities that are more serious, let’s focus on that and leave our community alone when it comes to trying to take care of our medical needs through native plants,” said Gallo. “Many of us are using the natural plants to help us not only with our mental needs, but our physical needs and so I’m here to support that.”

The Oakland measure would decriminalize mushrooms containing psilocybin, as well as the psychedelic plants ayahuasca, cacti and iboga. The measure is part of a wave of decriminalization efforts nationwide that some proponents call a “psychedelic renaissance.” A ballot measure in Denver to decriminalize hallucinogenic mushrooms was approved earlier this month. Other statewide initiatives are brewing in California and Oakland.

More than 100 people filled the Oakland City Council chambers. One person held a cardboard sign that read “Nature Is Not A Crime.” Another person clutched a cactus and wore a shirt that read, “I’m just here for the Fungi.”

“Oakland should decriminalize on one fact and one fact alone,” Gary Kono said to the four-person committee. “It never should have been criminalized in the first place.”

Many speakers said decriminalization is the first step in pushing the effort to use the plants to treat depression.

When committee member Rebecca Kaplan thanked Gallo for introducing the resolution, dozens of people stood up from their seats and cheered. Kaplan expressed her support for the resolution.

“Richard Nixon launched a war that we all know is stupid, racist, wasteful and expensive,” Kaplan said. “And it’s long past time for us to continue fighting Nixon’s war for him.”

Taylor expressed concerns on how to manage the use of the plants that wouldn’t put people in danger.

“It is something that could be taken advantage of,” Taylor said. “I want to make sure we are thinking through all the implications of how we are rolling it out. I think there is potential and value. My tendency is to make sure that we are really being deliberate in how we go about it and not just sort of opening it up carte blanche.”

Gallo said the discussion at the committee meeting is just the first step in pursuing decriminalization. He said he supported the resolution after being approached by Decriminalize Nature Oakland, a community group promoting natural psychedelics for mental health and overall well-being. The group made him see the positive impacts the use of natural psychedelics could have on people suffering from depression and mental health issues, he said.

“These plants have been in use for thousands of years, not only spiritually, but also health wise,” Gallo said. “(My grandmother) was a curandero (healer) in Mexico and she didn’t go to Walgreens to get her medication, they grew it in their backyards and that is how we healed each other for thousands of years.”

Oakland’s decriminalization efforts are particularly important because the city is a “microcosm” of the rest of the country, said Carlos Plazola, the director of Decriminalize Nature Oakland.

“This is about all of our connections to the natural world and to healing plants and fungi that have existed and co-evolved with humans for centuries,” Plazola said.

A growing interest in using natural psychedelics has re-emerged over the past few years, including from mainstream research institutions that had long avoided study of hallucinogens since the 1960s and ’70s.

Sarah Ravani is a San Francisco Chronicle staff writer. Email: sravani@sfchronicle.com Twitter: @SarRavani