I am not easy on water, having never learned to swim, flunking even the lessons in floating that I had as a small child at the swimming pool in Ft. Madison. The thought of being on water makes me apprehensive.
As the boatmen finish rigging the gear on our rafts, the rest of us find life vests. We don and attempt to fasten the vests, which are too tight or too loose. We adjust for each other the various straps until each of us, taking a deep breath, is able to snap our plastic buckles in place, and, then, breathing out, we feel our chests and ribs constricted by the now snug vests. Just before we board the rafts, the boatmen give us instructions on what to do if we are thrown in a rapid into the water and how they will rescue us. I waddle toward my assigned raft. I feel Frankensteinian—that is, like that man’s constructed monster—made of cast-off and miscast parts—my arms are propped outward acutely by the life vest, and both arms and legs are enclosed in hobbling layers of stiff, synthetic fabrics and raingear.
We motor down the cool morning river. The first small rapid splashes us with cold water. I shiver and wonder at the cold ahead. We stop soon—only a mile or so from the put-in at Lee’s Ferry.
This trip through the Grand Canyon with the National Park Service is to conduct vegetation surveys and make collections of plants. Lori, one of our leaders, introduced us yesterday to the projects for the trip, which are centered on the invasive shrub known as tamarisk or salt cedar. Tamarisk was introduced to North America from its native range in Eurasia and Africa in the 19th century. During the dust bowl years on the Great Plains, tamarisk were planted to create windbreaks to limit soil erosion. Since then, tamarisk have spread to the rivers of the southwestern US, where they form thick bands along the edges of rivers and washes, out-competing native trees, such as cottonwoods, and changing dramatically the vegetation of riparian zones. Tamarisk are common along the Colorado River, and they became especially prevalent in the Grand Canyon after the Glen Canyon Dam was built upriver. The dam regulated water flow, eliminating seasonal flooding of riparian zones in the Grand Canyon, which allowed the proliferation of tamarisk and various other changes in canyon ecology. Lori tells us that the Park Service has not attempted to manage tamarisk along the Colorado River, but they are working to control its spread in side canyons (see this link). Our trip is devoted partly to surveys of side canyons where tamarisk has been removed to determine the consequences of the removal efforts—whether tamarisk or native vegetation is returning—and monitor for the spread of tamarisk.
A second facet of our trip is to survey for the presence and spread of tamarisk beetles. A few years ago, biologists in Utah began to experiment with a natural predator of tamarisk—a beetle (Diorhabda carinulata) that forages and reproduces only on tamarisk—as a means of controlling population spread of the invasive plant. The tamarisk beetles have moved south from their release points and have settled on tamarisk populations in the Grand Canyon. The Park Service is interested in studying the spread of the tamarisk beetles and whether they can help limit the tamarisk invasion. Our crew has been armed with insect nets and instructed on sampling for tamarisk beetles and beetle eggs. At our first stop along the river, a team from our rafts samples for beetles using the insect nets, which they sweep across the branches of the tamarisk.
My mission on this trip is to collect plants, and I am joined by colleagues, Wendy and Max. Wendy has been studying the flora of the Grand Canyon for many years, and she knows intimately the place and the plants. Max, too, knows the plants of the region exceptionally well. While much of my research involves plants of the Colorado Plateau and more generally the intermountain western US, I do not know the flora of this region like Wendy and Max. I feel like an amateur in the face of their floristic knowledge. While Wendy and Max marvel at a sedge that grows near the water’s edge, I wander the gravelly bar. I find a lovely Orobanche (broomrape), which Wendy tells me is unusual this far northeast in the Grand Canyon. I find also a population of Cronquist’s blazing star (Mentzelia cronquistii). The blazing stars are my reason for being here. I have been studying the evolution of blazing stars for several years, and Wendy and I believe that we have discovered a new species of blazing star in the Grand Canyon. This trip through the Grand Canyon will give us a chance to explore for additional populations of the new blazing star and give me the opportunity to sample the diversity of the various mentzelias that are here.
We stop next at Cathedral Wash, where Apache’s plume and prince’s plume are in bloom, and a hackberry in bright leaf has fruits. As the day edges onward, our stops to survey for tamarisk beetles become quicker, and there is little time to botanize.
The raft moves calmly on smooth water. I grow comfortable with the boat and the water. We are quiet in the afternoon, after shade descends on the channel. The shaded river has a wiggly blue path at midstream where sky and water, in a way, meet. Our course down the blue path is bordered by deep, rufous browns and viridian. Where the river manages a reflection of a sunlit cliff face, the water shimmers with orange.
We enter evening with a series of rapids. I grab a firm hold on a rope that secures our gear (and hopefully me). Each rapid begins with rolling arcs of shiny water—I am enamoured by the curve of water, and I would stay here on the rapid’s tongue where the water bends and shines like metal—and then we plunge into the holes where white, shattered water curves high, rising over the front of the raft, and back at us. The frigid splatter hits like shots, and we twist away, recoiling tensely, at each strike.
In the mid day heat, I had taken off my rain gear, allowing the rest of my clothes to become soaked. In late afternoon, when shade descended on the river, I grew cold and put on again my rain gear, which served to keep the cool air and chilling spray of water away from my skin, but the rain gear held a clammy cold from the wet clothes tightly against me. Is this a pleasure?—I wonder to myself. I am anxious to reach camp.
Sun shines on our camp. When we arrive the rafts must first be unloaded. We then receive instructions on how to set-up the kitchen and toilet. I shiver through the instructions—my shoulders are tensed against my chill, and I can hardly move in my drenched, cold clothing. When we are released, I take my gear to a pair of large boulders that will serve as the head of my bed for the night. Fleece pants, a dry, cotton shirt, and a fleece pullover are readily at hand in my pack, and I walk upslope behind the boulders to change clothes among the shrubs. In dry clothes, I warm quickly, and the pleasure of the place returns.
[this essay dates to 2 May]