Deb Malewski
Contributing Writer

Eaton Rapids has a new claim to fame. A new species of truffles, known as Tuber rugosum, was recently discovered in Eaton Rapids by Bryan Rennick on his property on Gale Road. Rennick, a horticulturist and fungi mycologist, works as a Truffle Cultivation and Morel Cultivation Plant Pathology Research Assistant at Michigan State University.
What exactly is a truffle?  Some consider it the “luxury cousin” of the mushroom. It is the fruiting body of a fungus that grows underground, usually in the shadow of oak or conifer trees. They are an expensive commodity due to their rarity, have a short shelf life, and are labor-intensive to locate and harvest.
Truffles often resemble small rocks, but they feel more like a bouncing ball, Rennick said. Some varieties have a pungent smell when fully ripe. Only a few species are sold as a food product, though, as many are too bland or too small to bother with. Older truffles, which are riper, have the best smell.
Most of the truffles that he finds don’t have much culinary value, Rennick explained, but as a mycologist, he uses them for their research value.
The truffles with culinary value growing in the area are Tuber canaliculatum and Tuber lyonii. Rennick has also found Tuber floridanum and Tuber brennemanii on his property, in addition to the new Tuber rugosum.
Rennick walks each day with a rake, making scratches in the dirt and leaves as he walks, turning over just an inch or so of soil to find the fungi, which grows on the tips of tree roots. He gently rakes the soil and takes care to smooth the soil down when done so as not to disturb the root system of the tree.
Truffle season runs from July to January, with the fall being the peak time for ripeness.
“They want to be dug up,” Rennick explained. “They have an odor because they want to be eaten by squirrels so that the squirrels will distribute truffle spores in their feces to make more truffles.”
“And if you watch the squirrels, and the holes they dig, that will lead you to truffles.”
What does the Eaton Rapids truffle taste like? “Underwhelming,” Rennick said. “Not much flavor or smell.”
“If anyone finds a truffle, I hope they will contact the MSU Bonito Lab so I can have the opportunity to get a sample of what is growing in the area,” Rennick said. They will “sequence” the truffles, he explained, to be able to compare the find to other species by their DNA.
“Identifying North American truffles species almost always requires DNA sequencing,” Rennick explained, “so if you find any, and we confirm that they are true truffles, I’d love to be able to take some photos and sequence it.”
In the past, pigs were used to sniff out truffles, but they tended to eat what they found. Dogs have been proven to be just as effective, but they don’t eat what they find. Rennick lost his three-year-old German Shepherd, Dakota, last July from lymphoma. “He was just starting to get really good,” Rennick said, sadly.
Rennick’s property is also one of eight farms to be designated as a Morel Cultivation Research Site through MSU, a research project that is looking for ways to cultivate morels in Michigan. He is both a researcher and a participant in the project. The goal of the project is to expand the domestic morel markets, improve rural economies, improve economic sustainability, and improve soil health and crop diversity in Michigan.
Rennick also cultivates shitake mushrooms. He has set up shitake mushroom “gardens,” which are stacks of oak logs, on his property to grow the shitake mushrooms. The logs are infused with the shitake spawn and will produce the mushrooms the following year and continue to do so until the log is fully decomposed in five to ten years.
Rennick cautions people to use care with mushrooms found in the area: there are several poisonous species, including the very deadly Destroying Angel mushrooms that look like small puffballs before they grow to full size.
The Rennick family has a roadside vegetable stand at their home on Gale road in the summer where they sell all kinds of vegetables plus shitake and oyster mushrooms. Sales from the stand are used to cover the costs of their garden and to teach his children responsibility, Rennick explained. For more information about truffles and mushrooms contact Rennick at