A new Gold Rush is upon us in the Golden State of California.

But this latest wave concerns us with nuggets of a different sort: marijuana. California voters have legalized it, and now state regulators are adopting distribution rules and a plethora of weed-related laws ahead of a January 1 deadline to begin issuing retail licenses.

Make no mistake, from a purely business standpoint, the legalization of marijuana in California, home to Silicon Valley and the nation's largest economy, will sooner rather than later equate to a gold mine of opportunity for startups and established businesses. That economic boom includes everything from agriculture, real estate, banking, software, to security, paraphernalia, and you name it.

But one area being left out is the autonomous sector. Sure, a drone can already deliver you a pizza in California. Yet the California Bureau of Cannabis Control is forbidding the delivery of marijuana by an autonomous vehicle—whether from the sky or the ground.

"Transportation may not be done by aircraft, watercraft, rail, drones, human-powered vehicles, or unmanned vehicles," according to the emergency regulations (PDF) unveiled Wednesday by the state's cannabis bureau, which anticipates issuing 11,500 retail licenses the first year alone.

Sure, you can get pharmaceutical prescriptions via the mail, but not marijuana. That's gotta be done by a human-driven car, according to the regulations.

Deliveries may be made only in person by enclosed motor vehicle. Cannabis goods may not be visible to the public during deliveries. Cannabis goods may not be left in an unattended motor vehicle unless the vehicle has an active alarm system. Vehicles used for delivery must have a dedicated, active GPS device that enables the dispensary to identify the geographic location of the vehicle during delivery.

These new rules will put a damper on a handful of startups with names like MDelivers, Eaze, Trees Delivery, and others that have promised or demonstrated autonomous drone delivery of marijuana.

We urge anybody seeking to break into the California marijuana business to become familiar with the bureau's "Commercial Cannabis Business Licensing Program Regulations" (PDF). Thousands of rules here govern everything from seed to weed to delivery.

Seven other states also have legalized recreational marijuana. But don't expect an autonomous dope delivery sector to take off anytime soon. Generally, Federal Aviation rules require that aerial drones fly within a pilot's sight. And even if those rules were changed, which Amazon and other retailers are pressing for, local governments and states may still regulate how marijuana is distributed.