Image credit: Sunset over the Colorado River in Grand Canyon National Park. ©MATT PAYNE

Summer 2024

Weeding the Grand Canyon

By Melissa L. Sevigny
Summer 2024: Weeding the Grand Canyon

The search for an invasive plant, ghosts of the past and belonging on a journey downriver.

The gray dawn broke into birdsong over the Colorado River, and then the birds fell silent as generators began to hum, people shouted and trucks beeped, backing boat trailers down to the water. It was a chilly October day at Lees Ferry, the launch point for Grand Canyon river trips. Most in the crowd were river guides and guests on commercial expeditions or boaters with coveted private permits — and then there was my group, which was neither. I was a volunteer on a six-person crew with a work permit. It was our job to run the length of the Colorado River through the Grand Canyon and search out, dig up and kill an unwanted nonnative plant called ravenna grass.

I watched the hubbub, which had the festive feeling of a reunion; longtime canyon runners all seem to know one another. One kayaker approached my trip’s leader, Dan Hall, to chat about our plans. Then the kayaker grinned over at me, where I stood beside our three oar-powered, inflatable rafts, feeling slightly lost.

[SUMMER 24] Weeding the Grand Canyon Raft

Sevigny’s crew traveled in a flotilla of three inflatable rafts, which were loaded with equipment and food.

camera icon ©MELISSA L. SEVIGNY

“Thanks for weeding Grand Canyon,” he said.

I didn’t know how to reply. I had joined the trip to research the story of two University of Michigan scientists, Elzada Clover and Lois Jotter, who took boats down the Colorado River in 1938 to collect plants in the canyonlands of Utah and Arizona. They were the first botanists and first non-Native women to successfully run the Grand Canyon. After stumbling across Jotter’s archived papers in my hometown, Flagstaff, I began writing a book about their adventure, which is why I sought out Dan Hall and asked to join his ravenna-killing trip. I wanted to learn what it felt like to work on a river trip — to bushwhack and boulder-hop in search of plants, the way Clover and Jotter did.

But it was my first whitewater rafting trip — in fact, my first river trip of any kind. My only relevant experience was scudding a canoe across a lake, which is like petting a kitten to prepare for wrestling a bear. It would take us 15 days to travel 226 river miles from Lees Ferry to Diamond Creek, navigating 80 major rapids along the way. Some of those rapids are famous, with fables all their own. My imagination had started to spin nightmare scenarios: capsized boats, broken limbs, body-snatching whirlpools.

A waning crescent moon still hung in the sky when we shoved off into the river.

Danhall (as everyone called him), a longtime river guide from Flagstaff, had a calm and cheerful demeanor that I found reassuring. He had started weeding ravenna in the ’90s and became obsessed with rooting it out. The six of us on the crew had pooled our cash for food, brought our own camping gear and taken vacation days from our normal jobs to be here. Danhall, Mike and Greg each captained a boat. Amy and another Melissa were the crew’s professional botanists.

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Over 200 nonnative plant species grow in Grand Canyon National Park, about 80 of which are considered invasive — that is, capable of spreading fast and overtaking native vegetation. Ravenna is one of those. Left unchecked, it can form dense monocultures. It likes water and tends to grow close to the river, so it was our job to scour the banks for the telltale tassels waving like white flags above the tangle of vegetation, and also to stop at known hot spots. Danhall and the others on my trip had run the canyon before, dozens of times. It was like coming home for them.

But for me, everything about the experience was new. If I was honest with myself, I wasn’t sure I belonged. I didn’t admit it to my crewmates, but I was uneasy about my ability to keep up with the work and stay cool in an emergency, and nervous, too, about whether I’d prove capable at spotting the unwanted plant. In 1938, a newspaper described Clover and Jotter as being no more than “baggage” on their river trip, and though I knew the accusation was sexist nonsense, an irrational worry had taken root that I’d become just that.

The first big rapid in the canyon is Badger Creek, 8 miles downriver from Lees Ferry. I hunkered down in the rubber raft and gripped the rope that wraps its perimeter (called the chicken line). The boat tilted, bucked, rode the top of a crest and tipped into the trough on the other side. A wave slapped me — and it felt like that, a slap, sudden and cold. Water filled my mouth. I was shocked it tasted fresh, not salty. Grasping for a comparable experience, my mind had half-convinced me I was on an ocean. The boat came down into calm water, and I remembered to breathe. One rapid down, 79 to go.

Later, we pulled the boats ashore and hunted for ravenna. It can swell to the size of a haystack, but we were searching for the easy-to-miss young ones, too. We plunged waist-deep into the muddy water to edge round some boulders and reach a spot where ravenna grew. It didn’t look like much: a spray of pale green grass. Amy and Melissa showed me how to look for the white stripe down the center of each blade and the pale rounded shoulders at the base, like the bulb of an onion bulging out of the soil. I tried to fix the plant’s features in my mind, but I flubbed my first attempt at a solo identification, mistaking the native satintail as ravenna. What, I wondered, am I doing here?

Weeding Grand Canyon. It sounded ludicrous on the face of it. The canyon is, well, grand — a mile-deep crack in the planet’s crust, its oldest and deepest layers forged in the Earth’s furnace before multicellular life arose. My ravenna-digging shovel might as well have been the size of a toothpick.

I was surprised when I first read Clover and Jotter’s plant list, to learn exotic plants had already crept into the river channel by 1938. The two botanists documented more than 400 native species and 17 nonnative ones, transposed from Europe and Asia. Their plant list was not only a stunning catalog of the region’s rich biodiversity, but also the first published record of the inner canyon’s weeds.

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Neither Clover nor Jotter used the term “weed.” They listed native and nonnative species together in one long alphabetical jumble. They were evidently unconcerned about the sanity of future scholars, but their joy in weird botany was palpable in their journals. Clover, then 41, was the adventurous one, obsessed with cataloging cactus. Her protege, Jotter, was 24 years old and less sanguine about boating a river described in newspapers as a “graveyard” and “blind maze.” She packed all her belongings in boxes before she left, conscious of the real possibility that she might never return.

Both women came to enjoy the exhilaration of whitewater, which did not comfort me as much as I hoped it would. My idea of a jolt of adrenaline was two cups of coffee before breakfast instead of one. Now I began to understand what Clover must have felt when she wrote in her diary, “You’ve no idea how difficult it is to keep the mind on mere plants when the river is roaring & the boats are struggling to get thru.” It was hard to scan for ravenna when the anticipation of a rapid tingled down my spine. I felt a bubble of nervousness in my stomach when, near the end of our first day, we approached House Rock Rapid.

The river was low and bony. My waterproof river guide rated House Rock an 8 out of 10 in difficulty at the current water level. Mike, my boatman for the day, rowed hard on a diagonal path, and the boat grew sluggish when a wave pummeled us. I unclenched my fingers from the chicken line and scooped out water by the bucketful until we arrived in quieter water, drenched to the skin. “At least I am useful in bailing,” I wrote halfheartedly in my journal that night, after we made camp on a sandbar. “Not sure how else useful I am. Everyone is so experienced and sure of themselves. Practiced tying knots today.”

A wave slapped me — and it felt like that, a slap, sudden and cold. 

I woke to the descending notes of a canyon wren singing somewhere nearby. I’d never heard the bird before, and I was surprised to recognize it instantly from descriptions and online recordings — liquid, splashing notes like water running over rock. A thrill ran through me. Time to get my river legs.

That afternoon, we combed a sandbar for ravenna and found none, which was encouraging. The fewer plants we found, the better for the river’s ecology. Ravenna is tough. Sold in garden stores as an ornamental — and it is rather pretty, with its oversized, feathery plumes — it was first documented growing wild around Lees Ferry in 1981 and quickly spread downriver. Its seeds can float on wind and survive more than a year immersed in water. Hualapai Tribal member and ecologist Ka-Voka Jackson spent years experimenting with ravenna removal in nearby Glen Canyon National Recreation Area. Herbicide treatments and hand-pulling appeared to work, but baby plants could pop up and dead plants re-sprout from the root, zombie-like, less than a year later. The only way to triumph over ravenna, Jackson found, was to keep weeding, year after year, decade after decade.

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As we traveled downriver, the canyon walls rose higher, or rather, the river burrowed deeper, and the weather cooled. Tiny orange butterflies crossed the river’s expanse. I felt more settled by day four, enjoying the long stretches of calm water between rapids, when a profound stillness settled over the boats and cicadas buzzed lazy lullabies. Mesquite trees thickened on the sandbars, and we spent a few miserable hours bushwhacking into a dense, thorny grove to root out five smallish ravenna plants.

Why ravenna? I wondered. There were plenty of other nonnative plants on the riverbanks — plushy mounds of Bermuda grass and spiky sprigs of Russian thistle — but we didn’t stop to dig them out. In 2009, the National Park Service published a formal assessment of nonnative plants in the Grand Canyon, prioritizing their removal based on several factors: what ecological damage they can inflict, how quickly they spread, and how feasible it is to get rid of them. Ravenna was one of 10 species in the inner canyon on the high priority list. Unfortunately, removal work is complicated by climate change, which jigsaws ecological communities into new arrangements and, in the Grand Canyon, is expected to favor nonnative plants. There’s no going back to the past. We couldn’t remove every weed in the park, or, if we did, stop seeds from blowing over its boundaries. But we could choose one problem and get to work. Ravenna had champions — or rather, challengers: ragtag volunteers who, in the face of formidable changes, had found one way to turn their love of this place into action.

I might have begun the trip for book research, but now I wanted to belong to this cadre of people. The canyon’s beauty and the river’s ferocity sunk claws deeper into my skin with every day that passed. I wanted to spot a ravenna on my own.

Day seven: halfway through the journey. Clouds gathered on the canyon rim above us and peeled apart to reveal specks of white snow. We entered the Upper Granite Gorge, all dark walls and shadows. Two bighorn sheep with curling horns watched us pass with calm eyes.

We ran down through rapid after rapid, pausing at Phantom Ranch, where Amy and Melissa disembarked to hike out; they only had time to run the canyon’s upper half. They bequeathed me a cot and a thick sleeping pad that I hadn’t known to bring. That night, I was wrapped in luxury but restless. We had pitched camp on a sandbar so small there was no relief from the nearest rapid’s roar. The sound woke something in my hindbrain: It was like a flood coming down the river, and my body was tensed to run. I wrapped a scarf around my ears in a futile attempt to muffle the sound. Close to dawn, I watched Orion shoulder through the cliffs as if climbing, ever so reluctantly, from layered, rumpled sheets.

Rubbing my hands on my arms in the chilly morning felt like grating two pieces of 220-grit sandpaper together. My hair in its ponytail was one single snarl; I hadn’t attempted to comb it in days. I rode in Mike’s boat and made myself useful bailing water. My arms ached. Down through infamous Crystal Rapid, down through the Gems. At Serpentine Rapid, an oar jammed, and, instead of cresting over the waves, we slammed straight through them.

A headwind kicked up on day 10, and the temperature plunged; rain was on the way. Not long after navigating Deubendorff Rapid, an odd-looking clump of grass snagged my attention. Wary after my earlier misidentification, I convinced myself it was a native plant. Then Greg, rowing the boat behind me, shouted “ravenna” and stopped to dig it out. I berated myself for losing confidence.

Cattail, I noted later, is more plushy. Beargrass: more sawlike. Phragmites: more leafy. All the plants that resemble ravenna but are not ravenna.

The storm hit after sundown. I had pitched my tent between a big boulder and a tamarisk tree, supervised by a curious sphinx moth. I lay awake inside, counting Mississippis between the lightning and thunder. The sound never seemed to stop booming down canyon, rattling away in the distance only to begin all over again. It rained all night and well into the morning. We huddled under umbrellas to make oatmeal and coffee. Even the ravens looked cold.

On day 13, we passed a broad beach with an arrow dug into the sand. It was a message for us: Someone on a river trip ahead had been watching for ravenna, too. We tied up the boats — I still felt clumsy with the half-hitch knots — and followed the arrow into the brush. Two monster ravenna plants, taller and rounder than Christmas trees, confronted us. We clipped, counted and bagged their silvery plumes — more than a hundred of them — to carry out. Then we attacked the plants with shovels. We wrapped our arms around them, pulling and pushing. It took several hours to pry them loose and hoist the carcasses into trees so the roots would dry out.

I found the work oddly satisfying. Weeding Grand Canyon didn’t seem so ludicrous now. It felt like attention and care. It might not be possible to eradicate ravenna — what with ravenna plants still sold in garden stores and fresh seeds floating down from Glen Canyon — but each plant we dug up made room for something else to flourish. When I spoke with Jackson, the ecologist, after my trip, I learned she also studied how to replant native species — particularly those that are culturally significant to Indigenous peoples. Those include sagebrush, used for medicine and ceremonies, and arrowweed, for basket weaving. Eleven Native Nations have ties to the Grand Canyon, and its human history stretches back thousands of years. Many seemingly “wild” plants that grow here — agave, skunkbush sumac, mesquite — really evolved alongside their human harvesters. The Grand Canyon’s inhabitants have always weeded, planted and pruned.

The arrow in the sandbar made me wonder if there was a way to harness the energy of the Grand Canyon’s roughly 5 million annual visitors. Community science on a massive scale would be challenging — my own struggles to properly identify ravenna illustrated that — but for a moment I allowed myself to daydream about the possibilities. Sandbars cleared of tumbleweed before the bedrolls came out each night. Bundles of camelthorn and cheatgrass carried out with every expedition.

[SUMMER 24] Weeding the Grand Canyon author

The author, pictured with two monster ravenna plants, traveled 226 miles down the Colorado River from Lees Ferry to Diamond Creek.

camera icon ©MIKE KEARSLEY

Jackson told me whenever she rafts the canyon, she pulls out nonnative plants at campsites and picnic spots, but she knows it’s impossible to clear every species that doesn’t belong. When I asked her “why ravenna?” she told me it’s a success story. Danhall and other volunteers used to find upward of 10,000 ravenna plants on every weeding trip. Lately, the annual count was down to a few hundred.

“A few people throughout the years have been able to organize and, through personal passion, manage this plant,” Jackson said. “There’s a light at the end of the tunnel now, and we’re reaching for it.”

On our last day on the river, we split into pairs to comb a wide, cobbly sandbar. The first ravenna I saw jumped out at me cleanly, waving a single tattered tassel. “A solitary inflorescence,” Mike said wisely. He set to work rooting out the plant with a shovel while I kept searching. There! Another ravenna, and another. I’d heard mushroom hunters describe a similar experience when searching for morels; it was as if the pattern had snapped into place in my brain. I grew giddy with pride and relief — the same feeling I got when, the day before, the proper shape of the half-hitch knot came to my fingers without conscious thought, like I’d known how to tie it all along.

I found 14 ravenna plants in the span of half an hour, bringing our crew’s total for the trip up to 97. Mike, praising my work, confessed he was never much good at spotting the stuff, and I realized, rather late, that my impostor syndrome was unjustified. A tide of emotion filled me up from my boots. I came here to learn what Clover and Jotter felt when they ran the river, and it must have been this: after exhaustion and terror and doubt, the bone-deep delight of doing the work you came to do.

I was flooded with a rapid-worthy roar: Me! Rafter of rivers! Destroyer of ravenna!

We camped that night at Diamond Creek and woke early to deflate the boats. They rolled into surprisingly tight bundles. We loaded them onto trailers. Driving through Peach Springs on the Hualapai Tribe’s land, I felt an odd sense of shock when I spotted fake skeletons in front yards and pumpkins on doorsteps. It was nearly Halloween. The trappings of time in the world above the canyon seemed strange, almost unreal. I’d spent the last 15 days with no calendar or clock except the track of sun and star.

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“I’m so lonely for it now I can hardly stand it,” Clover wrote in her diary after leaving the river.

I hadn’t even reached the freeway yet, and I knew what she meant.

Nine months after my book was published, an invitation arrived in my inbox from a river guide at Holiday River Expeditions, who wanted to know if I’d join her on a rafting trip through Cataract Canyon in Utah’s Canyonlands National Park to share Clover and Jotter’s story. Cataract isn’t as well known as its famous sibling down the Colorado River, but it’s action-packed for an adrenaline junkie: two dozen big rapids crammed into a 14-mile stretch of whitewater.

I didn’t hesitate.

This was now my river — the river I first got to know in quiet rooms reading dust-ridden diaries and ink-smeared letters, and then by grit and wave and starlight.

I couldn’t be an impostor here; I was going home.

About the author

  • Melissa L. Sevigny

    Melissa L. Sevigny is the author of three books, most recently “Brave the Wild River: The Untold Story of Two Women Who Mapped the Botany of the Grand Canyon.” She lives in Flagstaff, Arizona.

This article appeared in the Summer 2024 issue

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