The big question, though, is whether cannabis is really that malleable. Would two genetically identical plants grow differently in two different climates? Anecdotally, the answer is yes. Scientifically, the data is just starting to trickle in.

Outdoor growers aren’t going to like hearing this, but a good place to start looking for answers is indoors. (Think of the indoor vs. outdoor debate like the gas vs. charcoal grilling conflict—it’s that contentious.) Indoor growing offers a controlled environment for messing with the phenotype, or physical characteristics, of cannabis. Same goes for the chemotype, or chemical balance of cannabinoids like THC and CBD.

Advances in LED and climate-control technology allow growers to take two genetically identical plants and expose them to different conditions, free from the vagaries of Mother Nature. “Small changes in temperature, relative humidity, nutritional availability, are going to greatly affect the chemotype, none more than light,” says Jeremy Plumb, director of production science at Prūf Cultivar in Oregon. “Light is going to be a gigantic variable.”

Plumb can recreate a bright, dry, and hot environment to emulate Kabul, or a more humid environment to mimic something more equatorial. This, Plumb is finding, has dramatic effects on how the cannabis grows and expresses cannabinoids. That malleability manifests outdoors as well. “If you give four different growers a genetic duplicate, they go into their different environments,” Plumb says. “When you go visit the plants after they've adapted and become productive, you'll see a huge range of morphology. Of course that will be reflected in the chemistry in the end.”

Cultivators like Prūf Cultivar are leading the research because it’s been hard for academics to study a federally controlled substance, but that’s changing. At Portland State University, for example, researchers have begun a pilot study into the cannabis terroir question—whether the soil itself changes the way a plant grows, as it might for the grapes that go into champagne.

They began by taking cannabis clones and distributing them to farms in southern Oregon. They tried to control for weather, in the sense that all these farms had different kinds of soil, yet shared a climate. The growers would also send the lab flower that has not yet been cured—another variable that could potentially change the plant’s chemical makeup.

“It's the same situation with the wine world, where you have climate and soil but you also have all these factors related to how the winemakers are actually making the wine,” says John Bershaw, a geologist at Portland State University.

The soil and cannabis samples from each farm would in theory reveal how the terroir might be affecting, for example, the expression of cannabinoids and terpenes (the oils that make weed smell like weed).

Depending on what the data turns up, terroir could help bolster the case that Northern California has something special, that the cannabis grown here is unlike anything else on Earth, in part because the soil affects the crop. "Even if it didn't, the appellation system would still have a role to play protecting local and rural farming economies and providing consumer protection," says Ryan Stoa, author of the forthcoming book Craft Weed: Family Farming and the Future of the Marijuana Industry. "So it's not to say that the terroir issue would be a death knell for the proposal, even if it was shown that it isn't as robust as it is for grapes."

California's farmers may be struggling now, but their troubles will grow all the worse when Big Cannabis moves in with giant indoor grow operations, churning out massive quantities of boring weed and driving down prices. That product might suit some consumers just fine. "I think there will be a large percentage of the consumer base that doesn't care," says Stoa. "They want the cheapest marijuana possible at the most potent level possible." But others might pay a premium for the certified Mendocino-grown stuff. "You can already see a connoisseur market emerging," he adds.

So it might be that Big Cannabis takes up the mantle of Budweiser or Coors, while the appellations of Northern California turn out the artisanal IPAs. With the right protections in place, perhaps the two worlds can coexist.

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