In the spring, The Nature Conservancy’s 33,000-acre Zumwalt Prairie Preserve in Oregon is known for its wildflowers like these silky lupine (in purple) and lampstongue ragwort (in yellow) found along Zumwalt-Buckhorn Road. The flowers are more than just background for a beautiful hike though. When plants bloom, they become easier to identify, making long-term efforts at the preserve to identify and monitor native and invasive plant species a little bit easier. Photo © Aaron Huey

Outtakes: Science on the Prairie

In the rural ranchlands of far eastern Oregon, scientists are studying wildflowers to learn more about the shrinking prairie.

Winter 2017

Not many people make the trek out to Zumwalt Prairie in far eastern Oregon. The buses don’t always run on time and it’s a six-hour drive from Portland. But for those that do make it in the spring, the wildflowers are rewarding—at least for a botanist.

“The wildflowers are just phenomenal,” says Allison Rossman, a botanist and former field technician at The Nature Conservancy’s Zumwalt Prairie Preserve. “The structure of the vegetation—there’s just so much [diversity].”

Each year, a team of technicians like Rossman and volunteers from all over the world make the trek to Zumwalt to examine the flowers because plants, it turns out, are easier to identify when flowering. Since about 2006, teams under Heidi Schmalz, who leads monitoring work at the preserve, have studied plots of prairie, identifying species, noting invasive plants and generally monitoring how the landscape changes.

At 33,000 acres, the preserve sprawls across both canyonlands and upland prairie and runs up against generations-old cattle operations. There aren’t many other neighbors out here.

“Historically a number of things made it difficult to cultivate,” says Schmalz, who lives on the preserve. For one thing, the soil is thinner in the area than the farm-conducive soil to the north. The elevation is higher and there are more rock outcroppings. “When homesteaders tried, they didn’t succeed very well. So, they switched to cattle grazing. That’s the only thing that works there as far as economically viable production.”

When The Nature Conservancy initially bought land in Zumwalt in 2000, it began developing partnerships with local ranchers, searching for ways to make ranching more sustainable (read the Nature Conservancy magazine story on these ranching partnerships here). It also began the monitoring work on the preserve, using some of that to help inform grazing decisions. Schmalz studies, for example, how cattle affect plants near rivers.

The team also more generally monitors sample plots of land over time, notes the locations of invasive species and looks at how prescribed burning affects plant composition. It’s a painstaking process that involves examining the details of the plants under lenses and comparing them to identification guides.

That’s one of the reasons why Schmalz is excited about the potential to begin using satellite imagery to look at the effects of grazing or examine plant coverage on a much larger scale.

“Any time we try to sample something across this landscape it’s always frustrating because the landscape is so big and our plots are so small and even if you put 100 plots out there you still always question whether you’re getting an accurate measure of the variability across the landscape,” Schmalz says.

Using data from Landsat—a long-running satellite imagery program through NOAA—could provide a broader view across whole pastures or entire ranches, she says. “We’re right at the cusp of starting to use that as a practice. We did the hard work of developing the model and now we can start using it.”

And because the satellite imagery goes back to 1972, the researchers could theoretically map vegetation amounts across the prairie going back decades, allowing both the conservationists and the ranchers to better understand how their land is changing.

It’s not a replacement for getting up close and personal with flowers, but it has the potential to give researchers like Schmalz quite a bit more information and direct where more monitoring should occur in the future.

This summer Aaron Huey, a photographer based in the northwest, joined the technicians and volunteers on Zumwalt Prairie. On assignment for Nature Conservancy magazine, he covered the work of local ranchers and of the conservationists on the preserve. Read the story here and see outtakes from his trip below.

In May and June 2017, Allison Rossman, then a Zumwalt field technician, helped lead a group of volunteers in identifying plant species found on the preserve. Here Rossman uses a magnifying lens to examine the flowers of a buckwheat plant, a common native plant in the area that is seen as an indicator of shallow rocky soils. “A big part of plant identification is based on the number and arrangement of the parts of a flower,” she says. “That little yellow bunch has probably 10 flowers in it.” Photo © Aaron Huey

In the canyonlands of the preserve, Rossman and volunteer Will Gilmour-White, visiting from England, examine plants in search of invasive weeds. When the volunteers find invasive plants, they often use a GPS unit to mark the location’s coordinates. Contracted crews return to marked areas later to remove or spray invasive plants. Photo © Aaron Huey

In addition to tracking down invasive plants, the team (including Rossman in this image) returns about every five years to certain plots of land in the preserve to monitor what species are found there. By sampling areas throughout the preserve and returning to them systematically, the researchers build long-term monitoring data on the health of the local environment. Schmalz’s team began monitoring some plots as early as 2004. Photo © Aaron Huey

The area’s first raptor population survey occurred in 2003. The birds like this juvenile Swainson’s hawk flying over the preserve caught photographer Aaron Huey’s eyes as he followed the researchers. “There were so many hawks that were always on the same posts,” he says. “I’d find them in the same places every day.” Photo © Aaron Huey

The preserve is largely made up of two landscapes: the canyonlands and the upland prairie. Outside the preserve, the land varies even more as it does here at Buckhorn Lookout. “It was not what I expected,” Huey says. “The Zumwalt River Valley was really steep and green with rocky and grassy slopes that looked almost like the coast of Kauai. It was so green and so steep.” Photo © Aaron Huey

“I had to army crawl into groups of cows” to get this shot, says Huey. (Huey says this works with “teenager” cows but not adults or babies. Still, don’t try this at home.) Schmalz’s team monitors grazing land to study how cattle affect the plants in the area or how they affect plants along streams. Based on those ongoing results, she says, “We might actually change our decisions about how to manage grazing.” Photo © Aaron Huey

Looking to the future, Schmalz is excited about the possibility of using satellite imagery to help monitor the prairie and nearby lands. “We now have a way of quantifying vegetation across a whole pasture or a whole landscape,” she says. “And that record goes back to 1972. All of the sudden, we can go back and map the vegetation amounts across this prairie going back decades.” Once the programming is set up, the information could be shared with ranchers who can map their own pastures and calculate historical averages for vegetation on their land. Here Sharon Gibson leads a herd on the Dwayne Voss cattle drive down the Zumwalt-Buckhorn Road. Photo © Aaron Huey

— NCM