Snow seeding to restore native plants to the prairieby Elizabeth Baier, Minnesota Public Radio
Weaver, Minn. — Joel Dunnette looks out on the snow-covered prairie of southeastern Minnesota and sees what should exist in abundance.
Nearly a century ago, this part of the Weaver Dunes Preserves was covered in native grasses and wildflowers. Nearby wetlands provided a habitat for turtles, snakes and grass and nesting birds.
The native prairie on part of the land has largely disappeared because of farming, but a new restoration project that uses snow seeding techniques could help restore native plants to the area.
"We expect in five years or so to really see some real blossoming of some of the native fauna after this flora gets established," said Dunnette, a prairie expert for The Nature Conservancy.
On a recent day, Dunnette showed a group of 30 volunteers how to spread seed over 40 acres. He poured native prairie seeds into an oversized garbage bin full of sawdust.
"We want to spread it widely," Dunnette told the volunteers. "So if you miss some square yards, that's perfectly all right. Given the snow, you're not going to be able to walk everywhere. It's going to be some work."
Dunnette, 60, worked as an information technology manager at Mayo Clinic for 31 years. He has a degree in biochemistry from the University of Wisconsin-Madison, where he first became interested in prairie restoration.
Seeding a prairie like this one in southeastern Minnesota is usually done in spring or fall, before the snow falls, said Dunnette, who wore heavy-duty snow boots and thick, brown gloves as he worked.
But the group he led spread 80 species of seeds on snow-covered ground to accelerate the restoration of Weaver Dunes, the state's largest barrens prairie. The prairie is located where the Zumbro and Mississippi rivers meet and includes a sand terrace. The area also is home to wetlands, including open water marshes and wet flood plain forests.
Volunteers spread rose hips, sand milkwheat and a variety of other grasses and seeds.
Snow seeding is unique because the seeds hit the snow, warm with the sunlight and sink to the ground. Dunnette told the volunteers the seeds they spread won't sprout very well until they've been cold and moist. That could take days, or a few months.
"Our getting them in the snow now, instead of waiting until spring, actually works with how these seeds are made to function," Dunnette said. "They need to have that cold period to signal to themselves 'okay, it's been winter, now it's spring. Time to go.' "
At the site, they spread out as evenly as possible on the field. Each person carried a bucket or paper bag full of the seed-sawdust combination.
Jeff Weberg flung the seeds as far as he could to spread the fairly small amount of seed in his bag over a large area. Weberg, 43, who lives in the small town of Hollandale, came to the conservancy with his wife Dolores, who takes an environmental studies class at a college in Austin.
"I really didn't even know what to expect 'cause she said they were coming over here to throw some seeds and I go 'how long can that take?' " Weberg said as he trekked through ankle-deep snow. "I didn't realize it was 60 acres."
His wife threw so many seeds she had to return for more.
"It's just amazing," said Dolores Weberg. She decided to go back to college to complete her associate's degree after more than 20 years. "I don't remember learning this much in high school."
"You want some?" she asked her husband? "You can have some and I just got a little bit in this area here. That should be enough."
For some, throwing seeds on snow might seem counterintuitive since the seeds don't hit the ground right away. But the Webergs think the seeding project is a step in the right direction.
"People usually take from the land," Jeff Weberg said. "This time, you're kind of putting it back to where it was. So it's kind of a neat feeling that years down the road, you can drive by and say 'Hey, I helped put that back to the way it used to be.' "
That's what the Nature Conservancy aims to do. But restoring native prairie is much more complicated than just planting wildflowers. It takes years for native plants to overcome invasive plants introduced by farming.
The Conservancy owns 767 acres of prairie. Until a year ago, 100 of those acres were used to grow winter wheat. The snow seeding project marks the first time people have tired restore prairie to the area in more than 100 years.
Nature Conservancy Regional Coordinator Rich Biske said it could take up to three years before any plant growth occurs. That's because the new seeds will first grow under a mat of existing vegetation. Until then, workers will have to mow or burn the prairie to help the new plants become established in the preserve, he said.
A restored prairie would provide an ever-growing nesting area for one of the largest Blanding's turtle populations in North America.
"The female turtles will come out of the surrounding wetlands areas in early June, late May, and they'll make a nest, dig a hole, lay eggs and return to wetlands," Biske said. "By putting prairie here, we open up 100 more acres to those turtles to nest in."
That means making an even better migration corridor for the turtles, as well as other map turtles, snakes, grass and nesting birds.