Before you continue:
I am not an expert on fungi. I wouldn't even qualify as a hobbyist. I just enjoy taking pictures of natures tiny little details. Sometimes, curiosity gets the best of me, and I find myself trying to figure out exactly what it is that I was looking at. The following post is the result of one such instance.

---

---

Last weekend, I got the chance to go for a relaxing stroll through the small wooded area on the back corner of the pasture. We were in between cold snaps; the previous few nights had dropped down into the mid to upper 20s, but temperatures on this day had made their way up into the 40s. I didn't expect to find very many insects out and about, so my primary objective was to find a few photogenic fungi - and I did find a few.

Poo-Shrooms

Original Image

---

These were growing in an old pile of cow poo. They were only ~0.5-1 cm in diameter. They didn't seen very remarkable to my unaided eye; I thought it was cool that they formed little canals, and that was why I took the pictures. It wasn't until I got home and looked at the images on my computer that I began to notice how the chocolate brown and the baby blue hues played against each other. I also couldn't help but wonder where those little canals lead to.

Wiry Mushrooms

Original Image

---

These little guys were clustered together in a little crevice on a rotting, still-attached branch of an oak tree. It looked like a good climbing tree, but there was only one branch that I could easily reach. When I tested it to see if it would hold my weight, it crumbled in my hand, and I found these cool looking mushrooms on one of the pieces. They were only ~1-2 cm in length, so I would have missed them had that particular piece not broken off in my hand.

Unfortunately

I have no idea what the above specimen are, and I don't even know where to begin the research to find out. However, I was able to find another mushroom species that looked somewhat familiar. I thought I knew what it was, or that I was at least close enough that I would be able to nail it down to the species level.

I Found A Puffball

Original Image

---

I found a bunch of these clustered together on a decomposing oak log that had long ago fallen from a tree. I kind of recognized them from pictures that I have seen posted on a "Mushrooms of Arkansas" forum group. Apparently, this was a good year for them, because people were finding them all over the place. This was one of the younger looking of the specimen that I found. Most of them were a darker brown and beginning to shrivel up.

Old Puffball

Original Image

---

Earlier in its life, this mushroom would have been white or tan to light brown in color. Those darker brown spots (they kind of resemble epithelial tissue, to me) would have been more like soft spines; however, they wear off as the mushroom ages.

Which Puffball Is It?

I knew these mushrooms by their common colloquial name, puffballs, but what I didn't realize was that the term 'puffball' encompassed an entire collection of different types of fungi. And, the thing about identifying mushrooms is that it can be extremely important to classify them down to the species level, especially for those interested in foraging for edible mushrooms (I am not close to knowledgeable enough for that!). So, I did a little bit of research and asked a few local experts, and I was able to verify my suspicion that this is most probably Lycoperdon pyriforme.

The Stump Puffball

One of the common names for L. pyriforme is the stump puffball. It earns this nickname from the fact that it is saprotrophic, usually found growing on dead hardwood or conifers where they get their nutrition by decomposing the wood. They have a habit of growing in clusters - sometimes scattered, but usually densely packed to the point of almost growing on top of one another. After looking at other pictures, I realize that I happened upon a rather small cluster.

Just A Small, Scattered Cluster

Original Image

---

What's In A Name?

As a collective group, puffballs get their name from the fact that the mature fruiting body is generally a roundish mass that eventually releases its spores by coughing them up into the air in a visible cloud. Some species of puffball are able to generate their own propulsive force to eject the spores. Lycoperdon pyriforme, however, must rely on some outside stimulus. As it ages, it will begin to develop a weak spot at the top of the fruiting body. At this point, something as simple as an animal bumping against it, a drop of rain falling on it, or even just a stiff breeze can jar the mushroom enough to send its spores poofing up into the air. Indeed, I did notice a spore cloud rising from one of the mushrooms when moved the log. Some believe that it was this phenomenon that led to the genus name for many of the puffball mushrooms ("lyco-" is of Greek origin and means "wolf"; -perdon refers to flatulence) and the other common name for L. pyriforme, the wolf fart mushroom. Now, I've never been around a farting wolf, but I can imagine that in a cold enough climate that puff of warm, moist air might look similar. (Don't lie! You just got a visual image, didn't you?)

The species name "pyriforme" refers to the pear shape of the fruiting body.

What's On The Inside?

After noticing that spore cloud, I got curious about what may be inside of the mushroom. If this had been a fresh specimen, then the inside would have been fleshy and white. However, as L. pyriforme ages, the inside begins to turn a yellow to olive color before eventually drying out and forming a brown, fuzzy mass of spores.

** A Note Of Caution *Inhaling large quantities of puffball spores can be dangerous. In fact, it can result in a pneumonia-like health condition called lycoperdonosis.

Wolf Fart Spores

Original Image

---

How To Identify A Wolf Fart

The fruiting body of L. pyriformes usually starts out round but takes on its namesake 'pear' shape as it ages. The mushroom will usually range from 2-3.5 cm wide and can be as tall as 4.5 cm. When they are young, the fruiting body will be covered by lots of small spiny projections; however, those wear away with age, as seen in my images, above. The pear shape is the result of the base of the mushroom pinching off where it plugs into the surface of the wood that it grows on.

L. pyriformes Plugged In

Original Image

---

If you are able to dig down into the substrate where the mycelia are growing, you will see a mass of mycelial strings that grow out from the base of the stem and spread throughout the growing medium.

L. pyriformes Mycelia In A Decomposing Log

Original Image

---

If you're really serious about identifying a wolf fart, you can do a KOH test, a spore print, and even look at the spores under a microscope. For L. pyriformes, there should not be any reaction to KOH on the surface of the mushroom. The spore print should be olive in color, and under a microscope, spores should be ~ 3.5-4.5 µm in diameter and appear round and smooth.

Dangerous Look-Alikes

Stump puffballs do have a few dangerous doppelgangers. For example, the common earthball mushroom, Scleroderma citrinum, can look very similar to L. pyriformes on the outside; however, it will be pale gray to black (depending on age) on the inside instead of the white color that we would expect to see in a young stump puffball or the brown color of an older specimen.

Scleroderma citrinum

Image Credit

---

It can also be easy to confuse the stump puffball with some of the mushrooms from the Amanitaceae family, including the infamous Amanita muscaria and Amanita phalloides.

*** It would be difficult to mistake the mature fruiting body of either of these mushrooms with that of L. pyriformes; however, both go through a button phase before the cap opens up to reveal the gills where they resemble a puffball. To rule these out, you can simply cut the specimen down the middle. If the inside is one uniform, marshmallow-like mass, that is a good indication that you have a puffball. On the other hand, if you can see a separation where the umbrella is forming but just hasn't yet separated from the stem, then you do *not* have a puffball.

In Conclusion

If you are interested in finding getting outside and finding mushrooms, it is not too late despite the cold. I spent an hour or so outside in the woods behind my house and found several cool fungi to take pictures on. I have no idea what some of them were (let me know if you do!), but based on my research and the advise of local experts, I am confident that I have identified one of the specimen as Lycoperdon Pyriformes.

Thanks for reading my post! I hope you found it both entertaining and educational.

Resources

Tom Volk's Fungus of the Month for November 2001
MushroomExpert.com - Lycoperdon pyriformes
Lycoperdon pyriforme by Gary Emberger, Messiah College
First Nature - Lycoperdon pyriforme Schaeff. - Stump Puffball
Missouri Department of Conservation - PEAR-SHAPED PUFFBALL
Lycoperdon pyriforme (Morganella pyriformis)