How to identify and avoid buying moldy weed
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- What is mold?
- What happens if you smoke moldy weed?
- How to check for moldy weed
- How to keep your cannabis mold-free
Mold is never a welcome sight. Not in bread or cheese, and certainly not in your cannabis. Moldy weed is not only disgusting, it’s dangerous. Consuming mold-infested weed can have some serious adverse effects. But how do you know if your bud’s been infected?
Nearly every legal state has some sort of microbial lab testing requirement for regulated cannabis sales. These tests check for mold and mildew in batches of marijuana. However, even legal markets have seen their share of moldy cannabis over the years.
Read on to learn how to identify and avoid buying moldy weed and how to store weed so it doesn’t get moldy.
What is mold?
Mold is a catchall term for fungus that reproduces via lightweight, airborne spores. Humans inhale or ingest minuscule amounts of mold every day. It is typically harmless in small quantities since a healthy immune system can successfully prevent any damage.
Mold found on marijuana buds, or flower, is the same kind that grows on other plants. Botrytis (responsible for bud rot ), Mucor, Cladosporium, Rhizopus, and Penicillium (the mold responsible for penicillin) are the most common. Mold thrives in humid or moist environments that lack proper air ventilation.
Mold found on marijuana buds, or flower, is the same kind that grows on other plants. Photo by: Gina Coleman/Weedmaps
In cannabis mold most often develops when the bud isn’t dried correctly, though it can form in earlier stages of cultivation, such as in a too-humid grow room. Improperly dried weed stored in an airtight container for curing creates an ideal breeding ground for mold.
Mold spores are tricky to eliminate. They can survive the intense heat of a lighter when smoking a hit and they don’t burn off in the oven when weed is decarbed. Some molds produce mycotoxins too, which can be carcinogenic.
What happens if you smoke moldy weed?
When you smoke moldy weed, you inhale the fungus directly into your lungs. Those with compromised immune systems are at risk of developing a lung infection. Smoking moldy weed is also dangerous for those with allergies to mold-based antibiotics such as penicillin.
A study published in “ Clinical Microbiology and Infection” 2017 found molds such as Aspergillus, Mucor, and other potentially harmful fungi in cannabis samples procured from northern California dispensaries. By smoking moldy weed medical marijuana patients risk fungal infections and other problems.
The bottom line is moldy weed cannot be made fit for use once contaminated. Always throw away moldy weed, even if your risk for infection is low.
How to check for moldy weed
Thankfully, there are several ways to determine if your flower is mold-free.
Use the naked eye method
Eyeballing your weed is by far the easiest way to check for mold.
Healthy cannabis should be covered in spindly, glittering trichomes. Trichomes are sparkly glands with tiny hairs that appear almost crystalline in structure, separated by distinct trichome nodules with space in between them.
These are significant signs to keep in mind as you visually examine your bud.
Some mold looks like cobwebs in the bud, leaving behind a cotton candy-like webbing that’s gray or white in appearance. This could also be caused by spider mites, but you don’t want to smoke bug-infested weed either.
Another type of mold looks suspiciously like kief but is far from the real thing. Powdery mildew is a form of fungus that leaves a gray or white powder-like appearance. It is usually dull and muted in color, and looks like dust compared to the sparkle of trichomes or kief.
Other mold signs are dark spots, gray or yellow fuzz, or a slimy residue. If you find mildew in your marijuana, quickly dispose of it and check the facility or container where it was stored to make sure it hasn’t spread to other buds.
Use your nose
The countless terpene combinations in cannabis present a wide array of aromas, from dank to exotic fruit to skunk. Moldy weed, however, has a very distinct and unpleasant aroma. Moldy marijuana smells like human sweat, urine, or musty hay, all of which are typically repulsive to the human nose. A quick whiff should tell you whether your weed’s been infected with mildew.
Moldy weed has a very distinct and unpleasant aroma. Photo by: Gina Coleman/Weedmaps
Sniffing isn’t foolproof, however. Some people are more sensitive to cannabis’ aromatic nuances than others, and some users who are allergic to mold may have a reaction if they sniff too closely. And some molds don’t produce a smell, especially infestations that have only just taken root.
Use tools to check for mold
Consumers can also detect mold in their weed using low-powered microscopes, many of which are cheaply available online. Under a lens, mold produces filaments that look nothing like bubbly trichomes. If it doesn’t look like weed, it might be mold.
Black lights also can help reveal mold spores in your bud. Most mold glows an eerie green when illuminated by a black light, making it easier to identify.
Review brand websites and media for recalls
The best way to protect yourself from smoking moldy bud is to purchase lab-tested cannabis from a licensed dispensary. However, the legal marijuana market is expanding more rapidly than testing facilities and regulations can keep up with. And where legal restrictions still exist, illicitly produced marijuana products can still contain residual pesticides, fungicides, and microbial substances.
Keep an eye on local media, brand websites, and state and city websites for recalls of particular batches of products to help you discover unfit bud.
How to keep your cannabis mold-free
Storage is of the utmost importance when it comes to keeping your bud free from mold. Marijuana exposed to improper temperature, light, humidity, and air risks mold development, but there are things you can do to extend your weed’s shelf life and health.
Storage is of the utmost importance when it comes to keeping your bud free from mold. Photo by: Gina Coleman/Weedmaps
First, make sure your weed is properly dried and cured. Most professional cultivators should do this right, but when growing your own bud, it’s essential to allow the flowers to dry correctly . The process can take up to seven days and should be done with care in proper environmental conditions. Correctly dried weed will cure successfully, maintaining the perfect balance between dry enough to smoke and moist enough to preserve the terpenes and trichomes. .
Store your bud in a cool, dry place but not in the freezer or refrigerator. It’s too cold, and the exposure to moisture is potentially mold-inducing. The ideal storage temperature for your flower is just below 77 degrees Fahrenheit.
Keep buds in airtight containers made of dark-colored glass. Mason jars and the like limit air and humidity exposure that could encourage mold development. Many dispensaries sell containers precisely for this purpose.
Finally, cannabis requires precise humidity levels to maintain its dry-but-not-too-dry, smokeable goodness . The humidity in your storage jars should stay between 59% and 63% to keep things perfect. You can buy disposable humidity packs, such as Boveda packs, to add to your jars.
How to identify and avoid buying moldy weed Copy article link to clipboard. Link copied to clipboard. Contents What is mold? What happens if you smoke moldy weed? How to
What happens when you smoke moldy weed
Mildew Kush doesn’t sound appealing, does it? It doesn’t, not just because it’s gross, but because it’s dangerous, too.
Unfortunately, legal markets have seen their fair share of moldy weed recalls over the past few months alone. In January, Michigan regulators recalled 48 pounds of medical marijuana due to mold.
A month prior to Michigan’s order, Colorado agencies recalled an entire batch of weed from one operator that affected at least 10 Denver-based dispensaries.
Also in December, Canada’s government weed supplier, the Ontario Cannabis Store, recalled 25,000 grams of pot after a customer found mold on her cannabis.
So the mold scare is real. Here’s how to ensure it never ends up in your pipe.
Related: What Moldy and Disgusting Weed Actually Looks Like
The easiest and most cost-effective method for spotting mold on weed is the naked eye. Tokers will notice something that looks similar to cobwebs on or within the buds. Spider mites also leave behind actual webbing that can look identical to mildew, but you shouldn’t be smoking those, either.
Powdery mildew, a form of mold, can sometimes look like dusted kief to the untrained eye. However, closer inspection will reveal the powder isn’t kief at all, but something that resembles sawdust or the dust produced by kicking a puffball mushroom.
Other signs of mold or mildew include dark spots on otherwise green buds, yellow or gray fuzz, or the presence of slime. (Yuck.) Sometimes buds may also appear as if they were rolled in confectionery sugar, another sign of powdery mildew.
The Nose Knows: The Smell Test
Weed comes in a wide assortment of aromas, from hints of berries to that chronic funk that smells like you just ran over a wild skunk. But two scents can tip you off to moldy weed: the smell of human sweat or urine.
Of course, no one should ever smoke weed that smells like pee anyway, mildew or otherwise.
The smell test has limitations, though. Some noses are more sensitive to the nuances of weed fragrances than others. And tokers who are allergic to mold-derived antibiotics like penicillin may experience an allergic reaction.
Additionally, some molds and mildews don’t produce any smells, especially if the infestation only recently took hold.
Science, B! Use a Microscope
Obvious signs of mold, like seeing webby crud all over your buds, indicate the infestation was there for a while. Sometimes, however, newer cases of mildews and molds are invisible to the naked eye.
In this case, consumers can still detect if their weed contains mold. This method requires a microscope. In the age of Amazon, however, digital microscopes sell for less than $30.
Again, recognizing mold on weed by eye, even the aided eye, takes some experience. Mold and mildew produce little filaments called hyphae. Hyphae look nothing like the bud’s natural glandular trichomes, so if anything looks out of the ordinary, it might be mold.
Check the Media and Brand Websites for Recalls
Another safe practice for finding out if your cannabis contains mold is by checking local media for reports of recalls. State or city websites, as well as some company websites, may also post notices.
Although checking the news for moldy weed may seem dorky, it has worked in the past. In the case of the Canadian recall mentioned earlier, the woman who reported the mold only caught it because she’d read a news story on the topic. She said she never would have checked had she not known mold was even an issue with legal weed.
Why Mold Threatens Good Health
Why even care about mold on weed? After all, isn’t mold a source of medicine, just like cannabis?
Molds and mildew are fungi that thrive in moist environments with poor air circulation. With weed, the presence of molds or mildews indicates the plants are diseased, not extra medicated.
While some molds produce antibiotics like penicillin, treating an infection by smoking moldy weed is a really, really bad idea. Those allergic to penicillin could react violently to smoking mold, much less smelling it. Other patients, like those with compromised immune systems, may be unable to fight off the mildew’s spores, leading to moldy lungs on top of smoking shitty weed.
Furthermore, some molds and mildews produce toxins, called mycotoxins, that can’t be burned away. And even worse, making edibles with moldy weed will transfer those toxins wholesale into the food. (Double yuck.)
Basically, get your cannabis from trusted sources. Inspect every purchase before ever flicking a Bic. And always remember: webbing belongs in dark corners, not on weed.
Moldy cannabis has increasingly become a problem in legal markets. How can you tell if your weed has mold or mildew without forking over thousands of dollars to a lab?