In Glen Canyon, a fight against invasive grasses

A young researcher seeks to make the Southwest more resilient to climate change.

 

Inside a lab on the fourth floor of the Science and Engineering Building at the University of Nevada, Las Vegas, Ka-Voka Jackson pulled from a brown sack a dried seed head of the invasive plant called ravennagrass. She slowly maneuvered the brittle branch out, and from its wispy ventricles tiny seeds poofed into the air, across the counter and onto the floor. A couple of them latched onto her long black hair. “Each of the seed stock plumes can produce thousands per plant,” she said, as she shimmied it back into the bag. “It’s a prolific seed bearer. They are very light, and they can travel by wind, float on the water. And it seems to spread very efficiently in this area.”

Jackson, a graduate student in the School of Life Sciences, was raised on the Hualapai Indian Reservation in Arizona. Her ancestral lands span 1 million square miles along the Colorado River. Since 2016, after completing a degree in Salt Lake City and moving to Las Vegas, she’s been studying how to eradicate Saccharum ravennae. The bushy plant, sometimes called elephant grass, grows up to 14 feet tall, in bunches nearly half as wide. It was introduced as a decorative landscaping plant in Ohio in the 20th century, and by 2001 had reached the Southwest. While its beauty and resilience make it a popular accent amid rock gardens and succulents, ravennagrass can push out native plants, like white sagebrush and willow baccharis, that play a role in the ceremonial and medicinal practices of the Hualapai and other Southwestern tribal nations.

Ka-Voka Jackson monitors plots of ravennagrass, in Llewellyn Gulch, that have been treated with herbicide earlier this year. Part of Jackson’s research is testing to see how manual removal compares to spraying herbicide in stopping the plant’s spread throughout Glen Canyon Recreation Area.
Brad Jorgensen

When we met at the University of Nevada’s plant seed control room in August, it was nearing 100 degrees, and Jackson was dressed entirely in black, including canvas Toms shoes and rounded black glasses. Half a dozen tattoos decorated her calves and forearms. With the Southwest’s climate on a trajectory for prolonged drought and weather extremes, Jackson navigates the deep backcountry near Glen Canyon, around the Arizona-Utah border. Here, back home, she is working to eradicate prolific and climate-change-resistant invasives and restore native vegetation.

 

Growing up in the early 1990s, Jackson took an early interest in the natural world. Her mother, the head of the Hualapai’s cultural resources department, took her on river trips down the Colorado. The year she was 5, she spent a total of seven months sleeping outdoors. She graduated from the University of Utah and went to graduate school at the University of Nevada, Las Vegas. As part of her graduate research, in collaboration with the National Park Service and Glen Canyon National Recreation Area, Jackson is now assessing dozens of plots, 100 square meters each, in five different canyons.

In April, she took a team of technicians into the canyons to kill or pull up ravennagrass and replant native plants. Jackson is also investigating whether passive re-vegetation — allowing the native plants to come back on their own — can work. Over the course of her program, she will return to monitor her plots, recording details from each to give land managers insight into which methods could work best for Glen Canyon National Recreation Area. “Given that the climate is dry and this is truly a desert, finding even one or a few techniques that restore native ecosystems would be a huge success in this type of difficult environment,” said Scott Abella, an associate professor who is overseeing the research.

University of Nevada, Las Vegas, undergraduate volunteers Kevin Berghel, Carmen Lee and Roland Viernes join a National Park Service technician, Mike Berg, to remove root systems of the invasive plant ravennagrass.
Ka-Voka Jackson

While Jackson’s research will help land agencies, she hopes the project can create a bridge between tribal nations and federal agencies, so that tribes can develop their own long-term ecological restoration plans. Eradicating ravennagrass completely will be difficult, but Jackson thinks a paradigm shift in land management is imminent. “Tribes still use these plants ceremonially, to build certain objects, medicine and food sources. We’re not dependent on them now; we have modern society and can go to Home Depot instead of building from thatch. But it’s more about keeping the culture alive.”

The challenge is mighty. Climate change is increasing the harshness of the Southwest. Recently, Jackson and a technician from the Park Service revisited her plots that had been treated this spring. They entered a canyon where a park technician had sprayed herbicide a few years earlier. As they wended their way through thickets of brush and shrub oak, Jackson saw a delicate hanging garden of native flora — in view of a bunch of encroaching ravennagrass. “We were both just like ‘NOOOOOO!’ ” she said. “It was really upsetting to see that even after the Park Service had thought it eradicated some of the ravennagrass in the canyon, it came back.” Still, she remains hopeful. “I myself am not going to eliminate all of the ravennagrass in Glen Canyon,” she said. “But I can figure out the best way to get rid of it.”

Paige Blankenbuehler is an assistant editor at NewTowncarShare News.