A poem of geography, and the signature of a catastrophe

If it had been a game of cards, and not merely science, J Harlen Bretz had gathered a straight flush. Nearly a century ago, after two summers in the field, he was ready to lay out his provocative case that a great ice age flood had rampaged across eastern and central Washington.

Some pieces of his argument were so compelling they scarcely needed help from the other pieces.

There were, for example, large calves of rock that just happened to show up, unannounced and unexplained, in places far from their mother outcroppings.

Bretz had not been the first geologist to notice them. But part of what set him apart was the intensity of his curiosity. He was determined to find an explanation. He referred to the wayward rocks as “erratic bowlders.”

Erratics, by definition, are large rocks transported long distances by ice. What caught Bretz’s attention, as early as 1914, were the dozens of granitic and metamorphic “bowlders” found resting atop basalt bedrock as far south as the Columbia River gorge and as far away as the Willamette Valley. That was strange. Ice was the only plausible means of transport, but dozens of large erratics—many the size of refrigerators or larger appliances—were dropped far beyond the furthest, documented advance of the Cordilleran glaciers.

Finally, in 1923, Bretz played his hand. Consistent with his other field evidence, he proposed that the scabland erratics southwest of Spokane had been ensconced in glacial ice that had shattered and become flotsam in an enormous ice age flood. Although hang-gliding and zooming around on a jet ski are palpably exciting, it can also be fun to just close your eyes and imagine icebergs on the crests of towering waves that overwhelm Spokane and spill out into the Columbia Basin at highway speeds. And then, as the water recedes, the icebergs ground themselves on hillsides, melting and releasing their cargos of rocks and at least one large meteorite (the Willamette Meteorite, discovered in 1902) to boot.

Bretz’s explanation of the ice-rafted erratics was easily the most vivid among his quiver of arguments for the great flood. The others were more technical—i.e. the “braided” nature of scabland channels, the absence of glacial till, and the power of the floods to quickly remove astounding volumes of soil and underlying basalt. But one feature, in particular, was both poetic in the way Bretz described it and hauntingly graceful in the way it actually appears on the landscape.

I think of them as the Bretz hills.

As a rule, all Bretz hills were once Palouse hills. Palouse hills are known and rhapsodized for their mesmerizing, dune-like crests that are the signature landform of Whitman County, for decades the nation’s leading county in wheat production. The hills consist primarily of windblown loess—silt created by ice age glaciers grinding across the landscape, seasoned with volcanic ash. Loess is incredibly efficient at holding soil moisture, which helps explain the prolific crop yields in the Palouse.

Whitman County doesn’t have a monopoly on Palouse hills. Rolling hills of fine-grained loessial and volcanic soils extend into northern Idaho but also to the north, west, and south, including parts of Spokane, Lincoln, Adams, Franklin, Walla Walla, Grant and Douglas counties.

What makes a Bretz hill different from an ordinarily beautiful Palouse hill is that a Bretz hill is a survivor. It has withstood the onslaught of ice age floodwaters and been distinctively re-shaped. There are several places where you can see what happened, but my favorite is state route 23 between the towns of Sprague and St. John.

Generally speaking, the “prows” of Bretz Hills point toward Spokane—the direction from which the water came—and the tails toward Pasco, which is where the water would eventually pool before heading out toward the Pacific Ocean via Wallula Gap and the Columbia gorge.

Starting at Sprague and heading east, what you see is classic scabland—the surface scrubbed to the bedrock, with just enough grass growing among the sagebrush to feed grazing livestock. Basalt buttes are in all directions, and so are a remarkable number of lakes and wetlands. It is cowboy movie scenery.

After seven miles, the landscape changes. On your right is the Whitman County town of Lamont. If you were to take the turn-off toward Lamont what you would see on your right would be the gnarly scabland terrain you’ve just traversed.

On your left, however, would be bucolic Palouse. But if you look closely at the boundary hills—those bordering the scabland to the west—they are not classic Palouse hills. Because they’ve been overwhelmed by torrents of glacial floodwater, their shapes have been changed. Their slopes are steeper and they are stretched in length so that they look, from above, like elongated tear drops.

Of course, Bretz was offering the photographs of the flood-altered hills as evidence, not as art. After all, he clearly knew he was launching himself into a process that would involve years of arguments. It would take decades to win the arguments. But that wasn’t his fault. He was right to begin with.

This is a good place to hand the writing over to Bretz, from his 1923 paper:

“Literally hundreds of isolated groups of maturely eroded hills of loess stand in the scablands. Their gentle interior slopes are identical with those far from the scabland tracts. But their marginal slopes, descending to the scablands, commonly are very steep…” “A very striking and significant feature of the steepened slopes is their convergence at the northern ends of the groups to form great prows pointing up the scablands’ gradient…It is impossible to study these prow-pointed loessial hills, surrounded by the scarred and channeled basalt, without seeing in them the result of a powerful eroding agent which attacked them about their bases…”

Generally speaking, the “prows” point toward Spokane—the direction from which the water came—and the tails toward Pasco, which is where the water would eventually pool before heading out toward the Pacific Ocean via Wallula Gap and the Columbia gorge.

If you were to go even further south, through Lamont, you would soon lose the pavement and pass on to a gravel road that continues to follow the edge of the scablands. What you would eventually see on the distant horizon are a fleet of Bretz Hills, their prows aligned parallel to one other, as if sailing toward Spokane. They are but one example of the “isolated groups” of loessial hills that Bretz described—Palouse hills that somehow survived the great floods.

If you’d stayed on Highway 23—instead of turning off to Lamont—you would likely sense that you’d entered the heart of the Palouse. The highway quickly becomes a twisting ribbon through grain covered hills, their slopes sprawling in all directions. But seven miles later, the scene repeats itself as the hills abruptly end as you near Rock Creek and enter the eastern-most braid of the scablands—this one a bit more than four miles wide. If you were to look south, you would see Bretz hills in the distance, with their ghostly prows pointed north. Then the highway really does enter the heart of the Palouse and makes its way toward the Whitman County seat at Colfax.

There is an aesthetic quality to the scablands’ tear drop hills. Yet the story behind their survival and re-shaping creates a parable and quiet instruction on how to photograph them, or at least how to try.

As Bretz noted, the tear drop hills exist throughout the scablands, though they are more common in the easternmost tracts. The landscape along the lower Palouse River as it approaches Palouse Falls is another area where the tear drop hills are hard to miss.

In his 1923 paper, Bretz offered photographs of two isolated examples—one near Rock Lake and the other near Palouse Falls, south of Hooper. They’re small black & white photos that merely capture his point about the shape of the hills, both in slope and alignment. Of course, Bretz was offering the photographs as evidence, not as art. After all, he clearly knew he was launching himself into a process that would involve years of arguments. It would take decades to win the arguments. But that wasn’t his fault. He was right to begin with.

Whether it’s “The Sisters” at Wallula Gap, the massive cataract at Dry Falls, or the Stonehenge-like aura created by “The Feathers” at Frenchman Springs Coulee, there are several “oh my god” destinations in Bretzland that don’t need a story, let alone a caption.

In their graceful lines and isolation, the Bretz hills don’t need a story either. There is an aesthetic quality to the tear drop hills. Yet the story behind their survival and re-shaping creates a parable and quiet instruction on how to photograph them, or at least how to try. And, thanks to Bretz, I don’t feel as though I need to insert a compass for direction, or a pickup truck for scale. He’s done the hard work. I just need to get the camera to work.

–tjc