It began when Debbie McDermott allowed her daughter Jamie to raise two sheep for a 4-H project. Eventually, her 165-year-old farm was transformed into a successful, family-run, custom fiber processing mill.

McDermott’s Stonehedge Fiber Mill, which opened in 1999 in East Jordan, Michigan, now produces more than 700 pounds of yarn monthly for customers in 38 states and Canada. It produces an additional 15,000 pounds monthly for its personal lines of yarn, including Shepherd’s Wool, which is milled and dyed in-house before it’s shipped and sold in about 300 shops.

“I really think the appeal is our yarn’s made in the U.S., and people are more and more going toward U.S.-made products as a support for U.S. companies,” McDermott said.

Most garments worn in the United States in the first half of the 20th century were American-made, but the decline of the American textile industry began after World War II, according to knitting and wool industries expert Clara Parkes. She’s a member of the American Sheep Industry — an industry trade group — and author of several books on knitting.

In recent years, however, there’s been a slow-growing demand for wool yarn that’s completely produced in the United States, from sheep to skein, Parkes said.

One reason, she thinks, could be that consumers are turning back to wool because of the environmental risks of microplastics in garments made from synthetics like acrylic, nylon and polyester. The microplastics are released into waterways when the synthetic garments are washed.

Locally sourced yarn helps not only the environment but local businesses too, Parkes said. “There’s the environmental impact of shipping goods all the way across the world and bringing it back, but now people are asking themselves, ‘What if I can get the wool here and just keep it here?'”

McDermott echoed that sentiment: “Shopping local is allowing farmers to raise and keep their animals on the farm.”

Consumer interest in locally sourced yarn inspired the Michigan Fiber Cooperative to produce a line, Fresh Water Fiber, which uses wool and alpaca from Michigan farms. It’s processed by Stonehedge Fiber Mill and dyed by Why Knot Fibers in Traverse City.

One store that stocks Fresh Water Fiber is Wool & Honey in Cedar, Michigan. Owner Melissa Kelenske said she buys from Michigan-based fiber artists and companies that focus on producing high-quality, ethically sourced yarn with attention to their environmental impact.

“I think the farm-to-table movement of eating local, shopping local — basically the major slow food movement — laid the ground work for the knitting industry,” Kelenske said.

Another yarn company that supplies Wool & Honey is Brooklyn Tweed, of Portland, Oregon. Knitwear designer Jared Flood founded the company in 2010 to “preserve, support and sustain” American textile production by doing business with sheep farmers, fiber mills and dyers across the United States.

The business concept “was not so much about patriotism as supporting local economies,” said Christina Rondepierre, Brooklyn Tweed’s marketing manager.

“It was also the revitalization of East Coast mills and dyeing houses and the whole U.S. textile industry so they could sustain income and make sure towns and business were able to stay afoot,” Rondepierre said. For example, the Harrisville, New Hampshire, Historic District mill village spins some of Brooklyn Tweed’s yarns. The village was declared a National Historic Landmark in 1977.

But patriotism, too, is helping to revive the American wool industry.

After Ralph Lauren drew flak for making its Team USA apparel for the 2012 Summer Olympics in China, the fashion company had all Team USA apparel for the 2014 Winter Olympics made in the United States. The yarn used for the closing ceremony sweaters was 4,000 pounds of Shepherd’s Wool from Stonehedge Fiber Mill.

McDermott was shocked when a Ralph Lauren representative asked her to supply the yarn.

“It was a mouth-dropped-open moment when I realized who I was talking to on the phone,” she said. “It was a neat experience.”