What the Tualatin Valley Looked Like Before

When the first Euro-American settlers arrived in the Tualatin Valley in the 1840s, they described the landscape as park-like. Most of the valley floor was open grassland with scattered Oregon White Oaks, a landscape type known as oak savannah, mixed with wetlands and lakes. The dominant grasses were Red Fescue and Tufted Hair Grass. It was beautiful, open country, and the settlers felt immediately at home in it.

There may be a reason for that feeling that goes deeper than aesthetics. Researchers who study human relationships with landscape have noted that our species has demonstrated a special affinity for mixed, open-canopy woodland and savannah landscapes ever since our emergence on the grassy plains of Africa. With their abundance of game and edible plants, their wide open views and their scattered trees offering shelter, these landscapes provided everything early humans needed. The park-like Tualatin Valley felt like home to the settlers because, in the deepest evolutionary sense, it was exactly the kind of place humans are drawn to. What they did not understand was why it looked that way.

The People Who Made It

The park-like landscape the settlers admired was not a natural accident. It was the deliberate and sophisticated work of the Atfalati band of the Kalapuyans, who had been managing the Tualatin Valley for thousands of years before the first wagon train rolled through. The history of oak savannah in the Pacific Northwest corresponds closely to the history of human presence here, both dating back more than 6,000 years.

The primary tool was fire. The Atfalati typically ignited the land in late summer or early fall, burning the valley floor in a controlled and purposeful way. What the settlers saw as open grassland was, in the most literal sense, a garden. The Atfalati maintained camas grounds across the valley floor, cultivating the starchy bulbs of the camas plant, a food staple, through careful burning that kept the prairie open and the soil productive. Fire also maintained the growth of tarweed, whose seeds were collected and ground into flour, along with Salal, Oregon grape, huckleberries, raspberries and bracken fern. Grasshoppers, collected as food after a burn, were another benefit. Deer and elk were herded by fire for hunting.

The Oregon White Oak itself is a product of this long relationship with fire. Its thick bark protects the delicate inner wood from burning, and its dormant buds are located low on the root collar, below the soil surface, so the tree can sprout even after a fire has passed through. Douglas-fir has no such adaptations. Over thousands of years of Atfalati burning, Oregon White Oak was favored and Douglas-fir was kept at bay, creating the open oak savannah landscape that the settlers arrived to find. The fires also limited invasive plants and acorn-boring insects, keeping the ecosystem healthy and productive.

Where settlers saw wilderness waiting to be tamed, they were actually looking at centuries of careful tending. The Atfalati had, in effect, shaped the entire valley to suit their needs. It was their garden. A very large, very sophisticated, thousands-of-years-in-the-making garden.

What Changed

When settlement began in earnest in the 1840s and burning stopped, the landscape began to change almost immediately. Douglas-fir moved in from the surrounding hills. The open oak savannah began to close as shade-tolerant species filled in the understory. The grasslands and camas grounds that had been maintained by fire for generations gave way to forest and scrub as the ecological relationship that had sustained the valley for millennia was quietly broken.

The two cultures looked at the same landscape and saw entirely different things. Where the Atfalati saw prime camas grounds, settlers saw potential pasture and cropland. Where the Atfalati saw managed oak woodlands, settlers saw cabin logs and lumber and well-drained agricultural fields. And where the Atfalati saw a necessary and beneficial tool, settlers saw wildfire as a threat to their homes and settlements. Burning stopped. The landscape began its long transformation.

The invasive blackberry plants that carpet so much of the Pacific Northwest today, and that many people assume have always been here, were not part of this landscape at all. What are now called Armenian Blackberries were not brought to Oregon until 1922, where they soon escaped cultivation and spread with the relentless efficiency that anyone who has tried to clear them from a fence line will recognize entirely too well.

What Remains

Several endangered Oregon species, including Kincaid’s lupine, depend on oak savannah habitat. At its peak, oak savannah covered a million acres in the Willamette Valley. Today only scattered pockets of the distinctive landscape of massive oaks and open grassland remain, remnants of a world the Atfalati made and maintained for thousands of years. Pure oak stands now survive mostly on marginal sites where other species cannot thrive and for which no other use has been found.

In the 1990s a movement emerged to protect and restore what remained. Organizations across the valley began working to bring back oak savannah, recognizing it as one of the most threatened habitat types in Oregon. That effort continues today.

The next time you drive through the Tualatin Valley and admire the landscape, know that what you are seeing is a shadow of what was here. And know that what was here was not wilderness but a living, managed, carefully tended place — the work of people who understood this land in ways that took the rest of us a very long time to begin to appreciate.

The Atfalati called this valley home. They shaped it. They burned it carefully, season after season, generation after generation, so that it would feed them and sustain them and remain beautiful.

It was their garden. We are living in it still.