The Jack O’Lantern mushroom is the more common name for the Omphalotus olearius mushroom, but there are several species the name can refer to.
The Eastern (Omphalotus illudens) and Western (Omphalotus olivascens) Jack O’Lantern mushrooms are the two common ones of these species found in the United States.
The Jack O’Lantern is a popular poisonous mushroom that got its name from its dark orange pumpkin color and the fact that it glows. It is also tied to the Halloween season as this species can be found from summer to late fall. This mushroom can be mistaken for other edible mushrooms but should not be eaten.
As this mushroom is commonly mistaken for other species, we will dive deeper into the facts we know and look at how to identify it.
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How to Identify Jack O’Lantern Mushrooms
Here are some of the characteristics that will help identify the Jack O’Lantern Mushroom:
Cap
Omphalotus olearius and Omphalotus illudens are very similar species with dark orange to golden orange colors that can fade over time.
One way to tell the two apart is O. olearius can have darker caps.
Their caps can grow to be around 3-20 cm (1-8 in), varying from vase-like to relatively symmetrical in shape.
They will also have a “nipple or navel-like” bump on the top center.
The margin will start as inrolled but can develop to be upturned.
Gills
Mostly straight and non-forking gills that are usually thin and close together.
The gills will be yellow-orange color and are lighter in color than the cap.
These gills also have a bioluminescent glow which may be visible in the dark if the mushroom is fresh.
Stem
These mushrooms can grow to be around as tall as the caps are wide, 3-20 cm long (1-8 in).
The color of the outer stem, or stipe, will be similar to the gills and interior flesh.
Spores
They have a creamy white/pale yellow spore print.
Location and Fruiting
The Omphalotus olearius species is primarily found in wooded areas of Europe, while the Omphalotus illudens species is found in eastern North America.
Omphalotus olivascens is known to be native to areas of California and Mexico.
Jack O’Lantern species always grow on wood and often dead trees. Even if you cannot see it, the substrate will be attached to buried wood in the soil.
They are commonly found in clusters; it is rare to find one JOL mushroom on its own.
Jack O’Lantern vs. Chanterelle Mushrooms
The Jack O’lantern mushroom is sometimes referred to as a “false or fake Chanterelle” because it can so closely resemble and be mistaken for an edible Chanterelle species.
Chanterelles often look like a “melted” version of the Jack O’Lantern with thicker veinlike or “false gills.” Chanterelles will not only be lighter in color but are found to have a more aromatic “fruity” scent. Also, while Jack O’Lanterns are often found in larger clusters and always grow on wood, Chanterelles usually grow in small clusters, or singularly, not on wood.
To compare, since we have covered the basics of the Jack O’Lantern, let’s now look at the general characteristics of Chanterelles.
Gills
Jack O’Lantern gills can appear to fork, but it is just a smaller gill growing close to another upon closer inspection.
On the other hand, Chanterelle gills are more like veins that fork and can often have a more wax-like appearance.
Color
Mushrooms often start growing at a darker color which can fade as it gets older. This will often make using color a hard way to tell species apart.
While Chanterelles can vary from completely white to golden yellow and even orange, the caps of Jack O’Lanterns are usually dark orange which can fade to yellow.
The interior colors are a better way to tell them apart as the Chanterelles should be clearly lighter.
Scent
It can be hard to catch the scents of mushrooms but Chanterelles are often described as having a more fruity scent that could be compared to apricots.
Opinions differ on the matter, but Omphalotus olearius and Omphalotus illudens usually have the basic earthy mushroom scent.
Location
You are more likely to find species of Chanterelles growing in smaller clusters or alone.
They also do not grow on wood as the Omphalotus do. However, Chanterelles can still be found close to or under trees.
Please remember that there are many different species of these mushrooms, and you should always consult an expert before consuming a wild mushroom.
Do Jack O’Lantern Mushrooms Really Glow?
Whether Jack O’Lantern mushrooms glow or not has been a debated topic for a long time.
The gills of Jack O’Lantern mushrooms do fainty glow a blue-green color. This glow is caused by a bioluminescent enzyme called luciferase. It is easiest to see the glow on fresher Omphalotus olearius & Omphalotus illudens mushrooms at night after your eyes are adjusted to the dark.
This is likely such a debated topic because the whole mushroom doesn’t light up, and the glow can be very faint or not noticeable at all.
It is very hard to capture on camera and most pictures of the glow, like this one, are doctored.
The same compound that lights up these mushrooms, luciferase, is also responsible for the glow of fireflies.
This substance is seemingly named after the devil, but the word “Lucifer” can be transferred from Latin to mean “light carrying or light-bearing.”
While fireflies use their flashing ability to warn predators and for mating purposes, mushrooms use them as a non-lethal bug lamp to help the continuation of their species.
It is believed that these mushrooms likely glow to attract insects which in turn help spread their spores around. They seem to “turn the lights on” at night, where it will be more visible to bugs that may do them a helpful favor.
What Happens if you eat a Jack O’Lantern Mushroom?
The Jack O’Lantern mushroom is non-edible. It is reported to taste fine when cooked and eaten but will most definitely produce an unpleasant experience afterward.
The Jack O’Lantern mushroom is poisonous and will result in gastrointestinal distress if eaten. While eating this mushroom will not likely be fatal, it can cause extreme nausea, vomiting, and body weakness. This mushroom is sometimes eaten when mistaken for edible Chanterelle species of mushrooms.
One Reddit user described the experience of mistakenly eating a Jack O’Lantern mushroom:
“I had the worst night of sickness I have ever had. I threw up more than twenty times, dry heaved, sweating, the chills, irregular breathing, etc.”
Jack O’Lantern Mushroom Poisoning – What to do
It is always better to be safe than sorry when it comes to mushroom poisoning.
Due to extreme vomiting caused by eating the Omphalotus illudens, multiple doctors have recommended receiving medical care. According to experts, if the Jack O’Lantern Mushroom is consumed, the affected may need to be monitored and receive intravenous rehydration. It is also necessary to test the basic liver functionality and potassium levels of the poisoned person.
Needless to say, you should always do extensive research before consuming wild mushrooms.
Omphalotus illudens Medical Research
In this video, Paul Stamets, a prominent fungi advocate, refers to an old adage when he states, “the difference between a medicine and poison is dose.”
He also talks about how mushrooms have great potential within them to “bolster our health.”
While you shouldn’t consume mushrooms to cure any diseases outright, these have been used to create the experimental antitumor compounds Illuden S and Irofulven.
Irofulven is derived from a toxin called Illudin, which is naturally found in the Jack O’Lantern mushroom.
Before anyone goes and starts selling the mushroom itself as a cure to cancer, the toxin Illudin in its natural form alone has not been proven to have many benefits.
However, it is an ingredient in Irofulven, which has shown to be effective in some ways to fight certain cancers. It is still very toxic and needs further testing.
It seems Irofulven is undergoing clinical trials in Denmark and there is still hope of realizing its full clinical potential.