In 2018, Johnson founded Yes Compost in Belgrade, Montana. It wasn’t part of his original plan. He majored in engineering sciences and worked as a mechanical design engineer for Mission Motors in San Francisco after graduation.
He switched gears in 2015 when a job as a ski coach, assisting Kevin Francis ’06 at Montana State University, popped up. At Dartmouth, Johnson had been on the Alpine ski team—with his twin, Erik ’06—as well as on the sailing team for four years. He won the men’s individual slalom title at the NCAA National Skiing Championships his senior year and was inducted into Wearers of the Green in 2009.
“In San Francisco, everybody had access to municipal trash compost and recycling,” Johnson recalls. “I was surprised to see little of that when I got to Montana.” He learned about the vermiculture composting method, which uses worms to digest raw material, and started a bucket pickup route around Bozeman, Montana, to harvest food waste. He first piled the scraps in large windrows outdoors, and once they had partially broken down, took some to his worms to create rich, high-quality compost for sale.
It’s rotting food, but because we have a beneficial impact on soil health, the more we grow, the more good we do.”
To keep the worms alive through the Montana winters, Johnson put his Thayer education to work. He consulted with Agrilab Technologies to design a small-scale heat-recovery system, capturing heat from the compost rows—which can reach 150 degrees in the interior—to warm the worm shed. “Karl helped us figure out what was reasonable and what components were durable enough for smaller systems,” says Brian Jerose, president and cofounder of Agrilab. “He’s gotten a lot of respect from people in the industry for what he’s been able to do.”
Johnson acknowledges the work at times can be disgusting. “It’s rotting food,” he says, “but because we have a beneficial impact on soil health, the more we grow, the more good we do. That’s incredibly satisfying.”
