The last time I went mushroom hunting, I was forced to break the law. It wasn’t anything major, of course, and I thankfully wasn’t caught, but I did spend the day on the outskirts of legality—not a usual workday for a food writer.

My friend “Bob,” an accomplished amateur mycologist whose name has been changed for obvious reasons, had invited me out to forage for golden chanterelles. There was just one caveat: I would have to agree never to mention where we were. Turns out Bob’s secret hunting grounds were not his at all. They were private property, and we would spend the day trespassing in order to acquire our bounty. Six hours later, we pulled into his driveway with more than 15 pounds of mushrooms. Living as an outlaw never tasted—or smelled—as great as this.

The world of mushrooms is a mysterious place, the buying and selling of them, especially the most coveted wild ones, historically as mysterious as their occasionally magical growth in nature: Trees die, branches fall, and a delicious edible fungus pops out of them. Truffle hunters guard the secrecy of their land as assiduously as the president does the nuclear codes. So while things aren’t nearly that cloak-and-dagger in Kennett Square, Pennsylvania—the mushroom capital of the world—there are precautions to be taken when visiting.

One morning this past spring, Aimee Olexy, of Talula's Table (102 W. State St., Kennett Sq., 610-444-8255) in Kennett Square and Talula’s Garden (210 W. Washington Sq., 215-592-7787) in Philadelphia, met me at the office of Phillips Mushroom Farms, one of the largest growers in Kennett Square. I had to sign a form saying that I was healthy (lest I carry any diseases that could infect the precious fungi). And I had to don a hairnet. And then, after a short pickup truck ride past horses and haze-shrouded houses in the distance, Peter Gray, grower manager for Phillips, guided me to one of several inner sanctums to which I would gain entry that day.

We walked into one of the mushroom houses, the air outside the door already heady with the telltale earthiness of what was living inside, and we were confronted by domes of white Agaricus—button mushrooms, in this case— nearly as far as our eyes could see. And this was only a tiny fraction of the more than 1 million square feet of growing surface that Phillips boasts. Southern Chester County, Kennett’s home, is the source of 65 percent of the mushrooms eaten in the US—serious business in this quintessentially quiet town, its quaint shops and low-key attitude belying its status as a powerhouse in the industry. And the amazing thing is that it all happened by accident.

“The mushroom industry started in Kennett Square because a guy who used to grow carnations and roses went to France and saw that they were cultivating mushrooms [there], and brought back some of the mushroom culture,” Gray explains. Turns out he was the perfect person to do so. “Back in the day,” Gray says, “they used to grow roses and carnations on tables, so underneath the tables was a lot of dead space, and out here in the country, there was plenty of raw material, horse manure and things like that. So he started it here, and it just kind of took off.”

Today Kennett Square boasts an astounding abundance of mushrooms, from the more familiar Agaricus, whose members include white button, cremini, and portabella, to the corsage-looking filigrees of maitakes, to the satellite disks of oysters. You even find pompoms, rarely seen puffs that look as if they would be at home on the sidelines of a Smurf football game, in the hands of miniscule cheerleaders.

For all the success that Kennett Square has in the cultivation of mushrooms, the culture here goes well beyond that. John Rush, who handles special projects for Phillips, brought me into the Woodlands at Phillips, the family home whose oldest portions date as far back as 1828, and that Rush himself helped restore. With its warm woods and abundant sunlight, it’s a picture-perfect evocation of the country good life. Here, Jill Phillips Gray and Linda Phillips Steller—two of the three Phillips sisters (Meg Phillips Rush is the other, and Sharon Phillips, who married into the family, is spoken of in the same breath)—explains how the Woodlands hosts mushroom-cooking classes, tours, lectures, and more.

The town itself has embraced mushrooms wholeheartedly. Kathi Lafferty, of the local attraction The Mushroom Cap (think gifts, food items, and, yes, even a mushroom exhibit), not only sells a whole range of mushroom paraphernalia, but she has also developed a phenomenal dried-mushroom snack called Snack N Shrooms that’s found a perfect home in Whole Foods stores around the region. Karen Petersen, who works at Burton’s Barber Shop, is teaming with Kennett Specialties on a product that aims to harness the almost astounding health benefits of the reishi mushroom.

Olexy, meanwhile, incorporates mushrooms into many of the foods she sells at the market at Talula’s Table and the dishes she serves at her internationally renowned restaurant of the same name—at least two dishes on every 10-course menu she creates incorporate the local bounty. Midway through my day of fungal research, in fact, she had me over for a spectacular lunch of deeply flavorful mushroom soup, a sweet onion, mushroom, and goat cheese tartlet, and a mushroom mac and cheese that, had I eaten it as a child, might have resulted in my becoming a mushroom farmer instead of a writer.

Then there’s the annual Mushroom Festival, now in its 27th year and held on September 8 and 9, which affords mushroom lovers the chance to experience all that the town and its flagship industry have to offer. Growers like Kaolin Mushroom Farms, C.T. Bartoli Mushrooms, and Griffonetti Mushrooms, among a slew of others, all band together with other local businesses for a weekend of food, education, farm tours, a carnival, and a classic car show.

The local mushroom culture itself is actually what drew Olexy to Kennett Square in the first place. “Aside from my mom living out [here], it was probably the number-one reason why I planted [Talula’s Table] where I did,” she tells me. “I looked at a lot of different locations for the shop, and I really wanted to be inside of a region that had a food force to it.

“I’ve loved food festivals all my life,” she continues. “I loved the idea that the Mushroom Festival existed there. [If] I wanted to do this thing that was a little culinary mecca, in a way, I wanted to be inside of somewhere that felt incredibly ‘foodie’ as a result of some kind of industry like that.”

It’s an industry that has not only shaped the lives of Olexy, Lafferty, Petersen, the Phillips family, and others, but also, in a number of important ways, the culinary culture of the United States itself. Pretty impressive for a small town an hour outside of Philadelphia.