The marijuana industry in California is poised to blossom, with large-scale production factories being eyed, if a proposal to legalize pot for recreational use is passed. Industry watchers say the new business could create tens of thousands of badly-needed jobs.

The proposal will appear on the November ballot as Proposition 19, and would, among other measures, legalize the use of pot in non-public places and possession of up to one ounce of marijuana. It is one of four states—along with Arizona, South Dakota and Oregon—where marijuana legalization is the topic of popular referenda.

If approved in California, possession of up to one ounce would be legalized with sale and consumption controlled by local government. Sale and use would be limited to those over 21 years old in non-public places.

“The cannabis industry is a retail agriculture food processing industry and we are a retail agriculture and food processing union,” Dan Rush, director of special operations for the United Food and Commercial Workers Union Local 5, based in northern California, told The Sacramento Bee. “If we were not on top of this industry and its emergence, we would be asleep at the wheel.”

Several California firms are preparing for a future where marijuana factories become a reality. In the San Francisco Bay area, several firms have already begun laying the groundwork.

Oakland-based companies AgraMed, Gropech, Marjyn Investments and Medi-Cone are setting aside factory space and negotiating with unions or working with local governments to be ready to hit the ground running if Proposition 19 is passed.

“I approached the city of Oakland with a question. If cannabis was in our community we could legally grow it on a large scale, tax it, regulate it, bring in union jobs,” AgraMed’s CEO and founder Jeff Wilcox told KPBS TV in San Diego.

In response, the Oakland city council passed legislation to allow for large-scale medical marijuana production.

“We’re hoping to see dozens, if not hundreds of employees producing these joints—and a full, integrated line, from hash to edibles, all high-quality, top-shelf bud,” Matt Witemyre, Medi-Cone chief of staff, told the Bee.