Within One Watershed:

Essays from Hackleman Creek 

Part 3

The Lake

Spring

Newly leafed cottonwood trees tower overhead as small waves lap at my feet. A warm mid-May breeze ripples Fish Lake, brimming with spring runoff. Its main pool, at least a half mile wide, narrows to a slender fjord and curves around a bend out of sight. Snow melting from the Hackleman watershed’s uplands has once again filled the lake, but not for long.

Three thousand years ago, lava oozed out of Nash Crater and flowed three and a half miles to block the ancestral valley of Hackleman Creek. This basalt barrier now briefly impounds the creek’s flow each year. Gradually, as spring gives way to summer, the inrush of snowmelt will slow and the remaining water will seep through the porous lakebed, shrinking the lake until it vanishes altogether.

Walking along the eastern shore, I spot two chartreuse heart-shaped leaves floating on the water’s surface; they seem to glow with green energy. These new leaves fell, perhaps in a strong gust this morning, from one of the cottonwood limbs hanging over the lake. Below them, curling and clumping on the soil beneath the shallow water, are last season’s fallen brown leaves. This layer of decomposing foliage will nourish meadow plants when they sprout after the meltwater disappears.

Turning away from the shore, I head into the narrow cottonwood forest hugging this end of the lake. The breeze carries a honeyed aroma, reminiscent of a sun-warmed beehive, emanating from thousands of freshly unfurled leaves above me.

Each newly emerged cottonwood leaf is covered with a sweet tacky resin that protects the tender leaves from hungry bugs. Honeybees collect this cottonwood glue and use it in the hive to seal out insect invaders and disease-causing microbes. Solitary bees use it to line small cavities where they lay eggs. I look down to see my boots adorned with resinous leaf bud scales that have fallen after bud burst.

The sweet-smelling leaves fluttering all around me formed as tightly-packed buds last summer and spent the cold winter months wrapped inside protective bud scales like those gummed to the soles of my boots. After the appropriate amount of time chilling in dormancy (which varies by tree species), growth inhibitors within the nascent leaves’ inactive cells began to break down. As temperatures rose and daylight lengthened, hormones kick-started photosynthesis, resulting in the riot of green above me.

Moving on, I come to several huge cottonwoods, each about four feet in diameter. A burly root reaches up from beneath the moist soil, reminding me that most of a tree’s workings take place out of sight. Beneath my feet countless tree roots draw in vast volumes of water from the soil. I lean against a gray trunk, furrowed with age. As this cottonwood’s roots soak up moisture, the vascular tissue in its inner bark pulls as much as 200 gallons of water up through the tree to its leaves each day. The leaves use most of the water to convert sunlight into food for the tree. Microscopic pores on each leaf transpire the remaining water as vapor into the atmosphere. This process hastens the annual drawdown of Fish Lake. When the last of the lake’s water disappears, cottonwood tap roots will strain to reach water trapped in underground pockets within the volcanic bedrock.

Paralleling the south shore, I watch two kayakers glide across the lake, floating above an area where, in a manner of weeks, black-tailed deer will leave pointed tracks in the mud as they nibble fresh grasses covering the lakebed.

Stopping for a sip from my water bottle, I sit on a large rock at the edge of the trees above the lakeshore. Looking out across the water, I notice my sole companion: a chubby little duck floating in the middle of the lake. Its chocolate-brown head, gray back and steep forehead confirm that it’s a female Barrow’s Goldeneye. I watch as she swims in small circles, repeatedly diving and surfacing. Each dive launches a new set of concentric ripples across the surface. Her hungry search for aquatic tidbits creates a moving piece of monochromatic line art on a liquid canvas.

Soon another bird paddles into view beyond the circling goldeneye. Looking through binoculars, I notice a dagger-sharp bill, smooth black head, black and white necklace and checkered back – it’s a migrating Common Loon pausing for a break on its journey to Canadian breeding grounds. As it slowly turns to show its profile, I see water beading up on the sleek dark feathers surrounding a ruby-colored eye. Scientists disagree about the purpose of the brilliantly colored eyes: some say it helps the loon see underwater when diving for fish, others maintain the coloration is a visual display for attracting a mate.

The loon floats low in the water as the goldeneye continues to circle and dive. These avian companions are transients on an ephemeral lake slowly draining away beneath them. I wonder how soon the lake will vanish this year . . . and the next . . . and the year after that. Because of the changing climate, it may eventually disappear forever.