As more states pass laws permitting marijuana use, the legal barriers to growing cannabis are crumbling. But wildfires pose risks to many outdoor growers in California and the Pacific Northwest.

Jonathan Vaught is CEO of Front Range Biosciences, a Colorado-based biotech company that breeds hemp and provides nursery expertise to cannabis growers.

He says wildfire smoke can temporarily block out sunlight. That can shorten the time the plant spends growing branches and leaves.

“It can stunt the growth,” he says. “It can even, with a photosensitive plant like cannabis … cause it to go into early flowering.”

That can reduce the overall yield.

Soot and ash can also settle onto leaves and soil. Some of it can be cleaned off, but much is still unknown about how wildfire smoke can affect the plants in the longer term.

Vaught says smoke could taint the flavor. Or even worse, if buildings or structures that contain lead or fire retardants burn, he says that toxic compounds can contaminate crops.

As the climate changes, wildfires are getting more extreme. So, while growers may see new opportunities as cannabis laws change, they may also face growing risks.

Reporting credit: Sarah Kennedy/ChavoBart Digital Media.