As we head into the heart of wildfire season (August-September), growers in California are on high alert after the disastrous wildfires of 2015, 2017, and 2018.
Julia Jacobson and her husband Samuel Ludwig of Aster Farms lost their cannabis crop in the Mendocino Complex Fire last year. “If you live in California, the wildfires will touch you in some way, somehow, at some point. As much as you can prepare, there is no way to truly anticipate what the experience is like, how terrifying nature can be.”
This year has been relatively calm in the Golden State due to helpful August rains. But if a wildfire comes, cannabis farms near it will have to decide whether to destroy their crop. Bud can still get tainted by airborne toxins like pesticides, ash, soot, insulation, fire retardant, building materials, and more, and would be a danger to consumers.
When It’s Necessary to Destroy Smoke-Stressed Plants
Cannabis in the seed stage may be fine and clean if toxic ash has not been introduced into the soil. Plants in the vegetative state can escape damage if toxins haven’t impacted their root systems.
Unfortunately, wildfire season tends to come when outdoor cannabis is in its reproductive (flowering) cycle, which is the most vulnerable time for contamination. Resinous flowers exposed to smoke from wildfires may be coated with dangerous toxins and foreign material—soot, hair, insects, excreta, or other adulterants.
According to Nelson Lindsley, cultivator, consultant, and owner of Poetry of Plants, when that happens, “You might as well start over.”
Farmers may not want to keep bud impacted by smoke because its growth and cannabinoid levels may be stunted. Studies comparing cannabinoid levels between smoke-stressed and control cannabis crops have yet to be published, but according to Lydia Abernethy, Director of Cultivation Science at Steep Hill, we do know that high levels of smoke can reduce UV rays, which promote important processes key to the growth of a plant, like photosynthesis, stomatal conductance, and transpiration.
What Farmers Can Do to Protect Against Wildfires.
Lindsley of Poetry of Plants says farmers often overlook soil testing, but when you’ve got potentially toxic ash settling into the ground and a plant that’s an excellent bio-accumulator, it’s important. He understands the burden: “It takes a lot of time and money to do it the right way.” But making sure your soil is healthy will give you more confidence that your plants are clean.
It may also be helpful for farmers to consider cultivars that are more resistant to wildfire. According to Abernethy, “Plants with denser bud structure or more foliage have more nooks and crannies for microorganism growth. Larfy or airy small popcorn buds may be less impacted by smoke/particulate contamination than large, dense colas. Plants that finish faster [e.g. indicas] may do better than varieties that take longer to flower.”
Some growers try to wash smoke/fire affected flower, but this doesn’t clean off the contaminants. Instead, Abernethy says, ”Extraction may be the best bet for farmers with reduced batch quality to remove impurities, but it might not work well in all cases as we still see about 25% of legal batches barred for entry due to pesticide contamination.”
As for getting crop insurance, insurance companies started to dip their toes into cannabis farming, but huge payouts from wildfire destruction have made them more wary.
For example, a Carpinteria farmer received over one million dollars from a private insurance company after the Thomas Fire of 2017 destroyed his crop; that same insurance carrier was expected to pay out another eight million to other operations that lost crops from that fire. Needless to say, that carrier is no longer offering cannabis crop insurance.
Image: (Noah Berger/AP Photo)