Mushrooms aren't an unusual find on an outdoor adventure, but there is one kind of mushroom that can be a little hard to pass on by without taking a few moments to appreciate them: puffballs.

Puffballs look like you think they do based on the name. They are spherical, ranging in size from smaller than a marble to larger than a soccer ball or even a beach ball. When you come across one, the urge to push down on it to watch the spores float up into the air like plumes of smoke or clouds of dust can be a strong one. 

So where can you find these hard-to-resist mushrooms? There are many different species of puffball, but most grow in open areas or grassy open spots in forests, the National Park Service reports. You can also find some species growing on fallen logs and decaying wood. 

Like many other mushroom species, puffballs are decomposers. They feed on organic matter such as leaf litter, dead grass, decaying wood and dead tree roots, in the process breaking it down, or decomposing it, and recycling the nutrients, which are then used by other organisms, according to the University of Illinois Extension. 

Puffballs aren't just waiting for humans to stumble upon them and give them a gentle — or not so gentle — push to send their spores out into the atmosphere. Even without human or animal intervention these mushrooms are able to release their spores. All it takes is a little rain. Once a puffball has matured and the spores inside are ready to be released, a single raindrop is enough to send them flying, according to the National Park Service.

All those spores — millions or even trillions of them — have the potential to become a new puffball, but hardly any do, and that's actually a good thing. The sheer number of spores in giant puffballs — the largest species and one of the most familiar — is almost mind boggling, measuring in the trillions, the National Park Service reports. If every spore in a giant puffball successfully grew into a new puffball, it would create a mass of mushrooms totaling 800 times the volume of the entire planet! 

Puffballs aren't just something to marvel at either. Their spores have antibacterial, antifungal and antimicrobial properties, and they can fight harmful bacteria such as E. coli, Salmonella typhimurium and Staphylococcus aureus (the bacteria that causes staph infections) as well as modern antibiotics can, according to the National Park Service. 

Knowledge of their usefulness is nothing new. Many Native tribes utilized the mushrooms for their medicinal purposes, including to help heal sores and burns and to stop wounds from bleeding, the park service reports. They were also used as a food source, as a fire starter when dried out and even worn around the neck to keep evil spirits at bay.

The term puffball doesn't apply to just one kind of spherical shroom. There are dozens and dozens of puffball species belonging to several different genuses, but the best known of them is the giant puffball. The giant puffball is indeed large. They can grow to be up to 20 inches wide and 20 inches high — larger than a soccer ball or basketball. The world-record-holding giant puffball was much larger than that even, measuring 5 feet long and 4 feet wide, according to Outdoor Illinois.

Giant puffballs are often found in forests, ravines and low-lying areas, but they can grow in any grassy area. They are white in color to start but will turn brown as they age, Outdoor Illinois reports. They are most often seen between July and September.

In August 2024, the giant puffball was declared Illinois' official state mushroom in a bill signed into law by Gov. J.B. Pritzker. The honor was bestowed on the giant puffball thanks to students from the Prairie School of DuPage in Wheaton. Students at the school researched, collected data and interviewed more than 100 stakeholders to determine what mushroom would be best to represent Illinois as the official state mushroom, according to a state of Illinois news release. They then held a school-wide election, with the giant puffball winning the vote.

“Thanks to the passionate advocacy of the Prairie School students, Illinois is deepening our connection to the natural world,” Lt. Governor Julianna Stratton said in a news release. “Now a cherished state symbol, the giant puffball invites us to marvel at the inherent beauty that exists in and on our land. In recognizing this state mushroom, we are collectively exploring, preserving, and passing on the joy of discovery to future generations.”

The common puffball, also called the gem-studded puffball, is another species that is often seen. They are whitish in color, with spiny or bumpy projections on the rounded tops, according to the Missouri Department of Conservation. These puffballs grow on the ground, either singly or in colonies. They grow to be 1 inch to 3 inches high and 1 inch to 2 1/2 inches wide. 

Another puffball you might encounter in your adventures is the stump puffball, also called the pear-shaped puffball. These mushrooms are typically beige or light brown. They grow on dead or decaying wood, so look for them on fallen logs and branches. They often grow in clusters, each growing to be about the size of a golf ball. They start out looking like many other mushrooms, but when they mature, they are hollow, Mass Audubon reports. Look for a small hole on top; that's where all the spores are released from.

The purple-spored puffball and brain puffball are two larger puffball species you might come across, although they are not nearly as large as the giant puffball. They both grow to be about the size of a softball, according to Outdoor Illinois. The brain puffball grows in woody areas, while the purple-spored puffball prefers grassy spots. The brain puffball is beige or brown and has a textured appearance, giving rise to its name. The purple-spored puffball is also typically beige or brown, and its spores are purple, hence the name.