How to Forage, Preserve, and Use Chaga Mushrooms

Chaga (Inonotus obliquus) is an esteemed medicinal mushroom that parasitizes birch trees in temperate and boreal forests around the world. It's a slow growing, rock-hard fungus that also happens to make a delicious beverage that is having its moment in the limelight. Chaga tea has been enjoyed for centuries by Siberian peoples and also has a history of use by Native Americans in North America. Because it's a slow growing fungus, there are some concerns about it being over-harvested, but aspects of fungal biology complicate that question.

Modern science's adulation with fungi is relatively recent as humans have been foraging and consuming mushrooms for their health benefits since well before recorded history. Our shared struggle for survival has scientists investigating the biological compounds found within mushrooms and how they may help the human body combat bacteria and disease. One of the greatest advancements in antibiotic medicine can be attributed to the introduction of penicillin in the 1940’s, a compound which originated from penicillium mold species. The lineage of medicinal discoveries spans from our ancient ancestors using polypores as medicine, to the discovery of penicillin, to today’s innovations in cancer treatment. These types of discoveries are what continue to make mushrooms, including Chaga, an incredible resource as a natural medicine.

Today, Chaga is one of the most sought after health tonics in the mushroom world next to Cordyceps, Lions Mane, and Turkey Tail. This is because Chaga has a host of medicinal properties, which include essential b-complex vitamins, potassium, and beta glucans (to name a few). It’s considered a super-food, packed with antioxidants that help boost immunity, stimulate the production of natural energy, and support overall health.

Among the numerous health benefits found in wild Chaga, probably the most important medicinal compound is betulinic acid. Chaga derives its energy from host birch trees by collecting bioactive materials found in its bark, such as betulinic acid, and storing it in the sclerotia (the harvestable part of Chaga). Betulinic acid has been studied in cancer research, with some recent studies discovering a potential link between the consumption of Chaga and the inhibition of certain cancer cells. (These studies are ongoing and require further investigation).

There are discrepancies between the levels of betulinic acid and other compounds present in Chaga in different regions of the world. Some working research suggests that Chaga grown in colder, harsher environments are more nutrient dense. Though it’s likely that the overall environment, altitude, temperature, species of birch, and quality of soil are greater pieces to the puzzle. When it comes to Chaga, there is still a lot more to uncover.

Little is known about the origin of Chaga mushrooms and it’s interaction with humanity. The earliest surmised use of Chaga dates back to 1000 BCE Siberia used by the Khanty people in rituals and folk medicine. It was believed that Chaga could help one “attain a long life”, and was also used to aid digestion and soothe skin sores. Eventually, the use of Chaga began to pop up all around the world including Europe, Asia and North America.

Today, the use of Chaga has slowly shifted into the mind's eye of popular culture for purposes not too far off from our ancestors. Truthfully, Chaga isn’t all that difficult to get your hands on either. You can find it in most organic food stores or online among other mushroom supplements. If you live in the northern hemisphere you might also find them in your neighboring forests. And for the average adventurer, foraging Chaga can be an incredibly rewarding experience.

If you’re interested in learning how to forage for mushrooms and live in an area with birch trees, Chaga is a great mushroom to start with because they’re easy to identify and they don’t have any poisonous look-alikes. Over the winter, we made a video about foraging Chaga in Maine which you can find by clicking the link below.

Chaga is typically found in the northern hemisphere growing on the trunks of mature birch trees. Although you can find chaga year-round, the best time to forage for them is in the winter because they’re easy to spot against the snow. They look somewhat like a dark, charcoaled burrell that are scabby and rough to touch.

You might have better luck finding Chaga in old growth forests due to their incredibly long lifecycle. In 2009, a 10-year study in China found that Chaga has an average growth rate of around one centimeter per year. So if you’ve ever encountered a large Chaga in the woods, it's safe to assume that it's been there for a while!

Besides Chaga’s unique appearance, you can also identify it by examining it from the inside. Chaga has a vibrant orange interior that indicates it’s edibility; the brighter the orange, the fresher the Chaga. It’s possible to find Chaga on other types of trees such as oak, poplar, alder, ash, and maple, but little is known about its edibility or health benefits.

Harvesting Chaga is slightly more involved than other fungi you might forage for in the woods. This is because Chaga is a dense, hard growth that isn’t easily removed by hand. For larger masses, we suggest using a mid-sized hand saw and cutting only what you will use - but you can also use a cement chisel and a mallet in harder to reach spots as well.

Regardless if you’re foraging wild plants or mushrooms, the number one rule in foraging is to take what you need and leave enough behind for the ecosystem to recover. If a plant or fungus is particularly rare in an ecosystem, it’s best to leave it alone. When foraging anything in the wild these rules are especially important. However, when it comes to mushrooms there are a few caveats. The regenerative property of mushrooms isn’t limited by the total amount foraged because mushrooms inhabit more of their ecosystem than their visible growth may indicate. Meaning, when you forage mushrooms you’re only collecting a small portion of a greater whole.

For example, picking a mushroom is like picking an apple off an apple tree. In the case of the apple, the majority of the organism is the tree. The part you pick is just the ephemeral fruit and has little impact on the greater organism. Similarly picking mushrooms has little impact on the mycelial network that isn't visible to the naked eye. In fact the largest organism that exists on Earth is a fungus, Armillaria ostoyae or the “humongous fungus”, with a mycelial network that stretches for about 3.5 miles underground. Despite the growing concern of overharvesting, you can rest assured that when you harvest a mushroom you’re not killing the whole organism.

Foraging chaga is a little different because it isn't the mushroom fruit that’s being harvested, it's the sclerotia. The sclerotia can simply be defined as the energy storage vessel of the mushroom. It’s typically a dense or hardened mass of mycelium that contains an amalgamation of life-sustaining nutrients essential for fungal survival in adverse conditions. Technically, there is no current evidence that suggests harvesting the sclerotia of Chaga harms the fungus or prevents it from reproducing. But, a good rule of thumb is to not remove all of the Chaga from the tree, and leave behind at least ⅓ of its total mass. 

Because Chaga is a parasitic fungus, it isn’t uncommon to find it on dead trees. In fact, the sexual reproductive stage of Chaga begins once the tree is almost, or completely dead. When this happens Chaga will slowly begin to form fruit bodies in the form of tubular pores underneath the bark. Once these fruit bodies have reached maturity, they will spread their spores in order to infect a new host. Once a brand new Chaga manifests within a different tree, it will then live for 10-80+ years and repeat the cycle again.

If you come across a Chaga on a dead tree, the sclerotia of the mushroom is likely already dried out, dead, or contaminated with mycotoxins. It’s generally recommended to avoid harvesting them.

Before harvesting Chaga, it’s highly recommended to consult foraging guides or experts for proper identification. Although Chaga doesn’t have any poisonous look-alikes, it’s extremely important to be 100% sure since there are adverse effects to consuming anything improperly identified.

The most common look-alike to the Chaga mushroom is the Tinder Conk (Fomes fomentarius) because of their similarities in color and hardness, and both can be found on birch trees. The differences between them are easy to discern:

• Tinder Conks have pores underneath the cap; Chaga does not have pores
• Tinder Conks grow in shelf formation on the surface of tree trunks; Chaga forms inside the scarring of trees
• Tinder Conks have mushroom “caps”; Chaga forms irregular shapes
• Tinder Conks are somewhat smooth; Chaga is scabby and rough to touch

It’s important to note that Tinder Conks aren’t poisonous, and in fact, highly valued for their medicinal properties. It’s theorized that Tinder Conks were used by neolithic humans as far back as 5,000 years ago. Ötzi the iceman, a five-thousand year old mummy discovered in the European Alps, was reportedly carrying two species of polypore mushrooms. One of which was the famed Tinder Conk.

Once you have a wild Chaga mushroom, it’s best to examine it for any impurities such as pieces of bark, bugs, pollen, or really anything you don’t want to grind down into a tea. You can remove these impurities with the brush back of a foraging Opinel knife or you can saw off any unwanted bits and pieces, but make sure not to remove the dark outer crust. This part should be easy as Chaga is fairly unblemished and requires little effort to clean.

When processing a lump of Chaga, it’s easiest to break up into smaller, palm sized pieces before drying it. Ideally, you’ll want to process Chaga the day you get it because it’s interior will be much corkier, and spongy on the inside. This makes it easier to break apart, even by hand. You can use a hammer, small ax, or even a chisel and a mallet to break up the larger pieces.

If you are unable to process Chaga the day you get it, it’s best to store it in a freezer where it won’t be susceptible to mold.

With your palm-sized pieces, you can dry chaga using a food dehydrator and wait for it to reach a moisture level between 0-7%. If you don’t have a food dehydrator, you can process them in a warm, dry, and well ventilated area until they become hard and crumbly. Avoid drying Chaga in hot ovens to speed up the process, as it’s possible to strip it of its bioavailable nutrients.

It’s important to note that drying Chaga is ideal for long-term storage. If you plan on using Chaga the day you get it, you can skip these steps.

At North Spore, we use a commercial grade meat grinder to break up large batches of Chaga.
For home foragers, a small manual meat grinder will work just the same!

Now that you’ve successfully dried your Chaga, you can either store it as is, or break it up into smaller pieces for teas and quick extractions. The best place to store Chaga is in an opaque container inside a dry, cool place (such as a tea cabinet).

Like the majority of mushrooms, Chaga contains many long-chain molecules and chitin within its cell walls that make it difficult for the human body to digest when raw. Below, we’ve detailed a few methods on how to properly extract the medicinal compounds within Chaga as a tea or a tincture.

A cup of Chaga tea is the perfect warm-up on a cold, winter day. Chaga has a subtle, and distinct flavor that’s much different from herbal teas - it’s pleasantly mild, earthy and smooth to taste. When sweetened and combined with a splash of cream, it could be compared to a cup of light roast coffee without the acidity. For some, Chaga may be considered an alternative coffee, as it has properties that boost energy without the crash.

Preparing Chaga tea is different from herbal teas - herbal teas are infused with hot water, while Chaga must undergo a process known as decoction. Decoction is an Herbalist term to describe a method of extraction by boiling or simmering a natural material to dissolve its compounds. Because Chaga has a tough exterior, this method is incredibly effective.

A few things to note:

• For shorter extractions (30 minutes to an hour and a half): Medicinal potency may be lower, but you can re-use chaga bits in future extractions.
• For longer extractions (8 hours or more): The medicinal potency may be higher, but this process takes longer and you might not be able to reuse chaga bits to create more tea. Less volume, but higher reward.
• The potency of your Chaga is indicative of its dark, black coffee consistency. If your tea continues to be transparent or light in color after significant extraction periods, then that Chaga is no longer potent.
• You can store extra Chaga tea in the fridge for no more than two weeks - if you plan on storing it for longer, you can safety store it in the freezer

Although hot water extraction is an effective and pleasant way to consume Chaga, it has limitations. A proper extraction will contain water-soluble compounds such as: melanins, polyphenols, polysaccharides, beta-glucans, as well as vitamins, minerals, and amino acids that support day to day wellness. While, alcohol extractions (tinctures), are better at capturing the medicinal, anticancer properties found in Chaga such as: triterpenes, sterols, betulin, betulinic acid, and lignin.

Step 2: Hot-Water Decoction

Place the marc portion in a pot or slow cooker and cover with just enough water to submerge it. Cook uncovered for two or more hours at just below boiling, adding water as necessary while the mixture reduces. Cool and strain the resulting marc, keeping the liquid portion (decoction).

Step 3: Mixing the Finished Tincture

Measure the volume of your liquid extracts (both the alcohol tincture and decoction). The final tincture product should be at least 25 percent alcohol for proper preservation, so knowing the proof used in the initial alcohol tincture prep is important. For example, if you used 100 proof vodka (which is 50 percent alcohol) and ended up with 12 ounces of tincture, half of that volume is pure alcohol (or 6 ounces). Therefore, the finished tincture in this instance would be 24 ounces; 6 ounces of alcohol, 6 ounces of water (from the initial alcohol tincture) and 12 ounces of decoction. Calculating the alcohol to water ratio needed for your final product is easiest if using pure liquor but can become confusing if using less concentrated alcohols. Keep the following equation in mind:

Tincturing is the use of alcohol to remove and ultimately preserve the medicinal compounds found in an herb or mushroom. Since chaga has both water- and alcohol-soluble compounds, a proper extraction will include both methods, called a “double extraction.” Adopted from Mushrooms for Health: Medicinal Secrets of Northeastern Fungi by Greg Marley.

Ingredients:

• Dried chaga, chopped or ground as finely as possible
• Grain alcohol (ethanol) or vodka (100 proof or higher)
• Spring water or distilled water

Equipment:

• Stainless steel or enameled cooking pot or a slow cooker (e.g. Crock pot)
• Cheesecloth
• Glass jars with clean, tight lids
• Liquid measuring cup with clearly marked graduations
• Chef’s thermometer with probe - optional

Step 1: Alcohol Extraction

Dried chaga should be crushed or otherwise reduced into the smallest pieces possible, using a hammer, mortar/pestle, or meat grinder. The resultant dry material should be placed in a glass jar and covered completely with alcohol, capped, and placed in a dark space away from direct sunlight. Shake or stir the material every few days, adding alcohol as needed to keep the chaga covered. After 2 to 4 weeks strain the mixture through several layers of cheesecloth and keep both the alcohol portion (tincture) and solid portion (marc).

Step 2: Hot-Water Decoction

Place the marc portion in a pot or slow cooker and cover with just enough water to submerge it. Cook uncovered for two or more hours at just below boiling, adding water as necessary while the mixture reduces. Cool and strain the resulting marc, keeping the liquid portion (decoction).

Step 3: Mixing the Finished Tincture

Measure the volume of your liquid extracts (both the alcohol tincture and decoction). The final tincture product should be at least 25 percent alcohol for proper preservation, so knowing the proof used in the initial alcohol tincture prep is important. For example, if you used 100 proof vodka (which is 50 percent alcohol) and ended up with 12 ounces of tincture, half of that volume is pure alcohol (or 6 ounces). Therefore, the finished tincture in this instance would be 24 ounces; 6 ounces of alcohol, 6 ounces of water (from the initial alcohol tincture) and 12 ounces of decoction. Calculating the alcohol to water ratio needed for your final product is easiest if using pure liquor but can become confusing if using less concentrated alcohols. Keep the following equation in mind:

A + B + C = 4A

Where:

A = Volume of pure alcohol (Initial alcohol tincture volume X percent concentration of alcohol used)

B = Volume of water in initial alcohol tincture (Initial alcohol tincture volume – A)

C = Volume of decoction

4A = the maximum volume of the finished tincture resulting from the addition of the correct volume of decoction

As an example, if you began with 190 proof liquor resulting in 12 ounces of initial alcohol tincture volume, the mixture would be 95% alcohol, and your equation for determining the amount of decoction to add for the final product would be:

(12 x .95) + (12 - 11) + C = 4A, or

11 oz + 1 oz + C = 44 oz, solving for C gives us 32 oz.

Keep in mind when calculating the volume of total alcohol and have to round off the result, round down. In this instance the final amount of tincture is 44 oz, therefore requiring 32 oz of decoction be added to the 12 ounces of initial alcohol tincture volume, giving us the proper 75 percent water / 25 percent alcohol ratio.

Combine the correct amounts of initial alcohol tincture and decoction. Stir or gently shake the mixture prior to dividing it up into smaller containers. Store in a dark space. Tinctures will last for several years if properly made and stored.

As both a tincture and tea, Chaga has been enjoyed for centuries by peoples across the northern hemisphere, and its potential use as a super food to boost immunity, natural energy, and overall health is entering the mainstream. Harvesting and preserving this important natural resource should be done with great care so future generations can enjoy the many benefits of this ancient medicine.

Chaga Research Articles:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6142110/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124789/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4684114/ 

Chaga Life Cycle:

https://www.annandachaga.com/pages/sex-life-of-the-chaga-mushroom 

History & Use of Chaga:

http://www.ethnoherbalist.com/chaga-extract-mushroom-tea-benefits/ 

https://www.bbc.com/travel/article/20210609-alaskas-mushroom-of-immortality 

https://www.medicalnewstoday.com/articles/318527#Nine-potential-benefits 

Betulinic Acid & Medicinal Properties:

https://journals.lww.com/anti-cancerdrugs/Abstract/2010/03000/Betulinic_acid,_a_natural_compound_with_potent.1.aspx 

https://journals.sagepub.com/doi/10.1177/1534735418757912 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6142110/ 

Additional Reading:

https://www.discovery.com/nature/the-largest-living-thing-on-earth-is-a-3-5-square-mile-fungus 

https://www.researchgate.net/publication/222280519_The_Iceman's_fungi 

https://www.nationalgeographic.com/history/article/tzi-the-iceman-what-we-know-30-years-after-his-discovery 

https://www.annandachaga.com/pages/harvesting-chaga 

https://birchboys.com/blogs/about-our-chaga/comparing-chagas-water-soluble-compounds-to-its-alcohol-soluble-compounds 

Marley, Greg. 2009. Mushrooms for Health: Medicinal Secrets of Northeastern Fungi. Down East Books.