A Landscape Dammed by Beavers, Grazed by Elk, Monitored by Wolves and Shaped by Fire

An interlude in which we explore the massive disruptions of agricultural civilization on a wild, human-tended landscape

[This is a draft chapter from the book I am co-authoring with Nikki Hill, tentatively entitled, “Don’t Blame the Messenger: A critique of the ‘invasive plant’ narrative.”]

Let’s picture ourselves in a hot air balloon, floating over a valley. Below us is a patchwork of agricultural fields, encompassed by straight lines and precise angles, crisscrossed by ribbons of asphalt and gravel; a landscape of human geometry continuous except where the courses of rivers and streams intercede. The hundreds of fenced polygons vary in hue over the season as certain crops bloom: yellow Canola, Camelina or Mustard; white Meadowfoam; blue Flax; crimson or pink Clover.

Every crop is planted with the goal of maximum density: Wheat is drill-seeded in crowded blocks. Hops climb wires held 15-20’ high by tall pols. Wine grapes hang on trellises hundreds of feet long. Peppermint, purple-stemmed and glossy-leafed, is packed into wide files. Sunflowers stand shoulder to shoulder. Hazelnut orchards are precisely laid out like military cemeteries. Close rows of Christmas tree march up the slopes where the soil is rockier. Nurseries raise hundreds of species of landscaping plants in thousands of plastic pots set out in the sun, under shade cloth, or in hoop-houses. Animal agriculture is also an element, and a few pastures hold cows, goats or sheep, being raised for meat, milk or fiber, and some long sheds confine chickens and pigs. The feed grain for these unhappy creatures is imported from other regions.

Only here and there do we see plots growing vegetables bound for farmers markets and grocery stores, such as Kale, Cilantro, Summer Squash, Beets, Radishes, Sweet Corn, and Pumpkins.

The biggest crop by far in this valley is grass seed, as in grass for lawns and golf courses. Virtually the entire US production of Annual Ryegrass, Perennial Ryegrass, Bentgrass, and Fine Fescue comes from here.ⁱ Over 50% of the total farmland is planted in grass seed.

This is the Willamette Valley in the US state of Oregon, one of the most ideal locations for agriculture in the lower 48 due to its fertile soils, abundant water, mild winters and reasonable summers.

To the east are ridges blanketed with conifers, and this landscape too is apportioned into ruler-edged sections, each containing stands of even-aged trees, all the same height, repeating like cut-and-pasted elements in a digital image. These are managed timber lands, most of it federally owned, for sourcing “forest products.” The ridges rise higher and higher, and eventually form the undulating spine of the Cascade Range, running north-south and punctuated dramatically by widely separated peaks of snow and bare rock, ancient sentinels to an entire region. From here on a clear day you can see St. Helens, her top scooped out by 1980’s eruption, then Hood, Jefferson, and Three Sisters. Out of sight in the north is grand Rainier and in the distant south, magical Shasta.

To the west, also running north-south, is the much lower Coast Range, also subdivided for plantation lumber and unlike the Cascades, mostly private. Beyond, suggested by an grey smudge over the horizon, is the sea. Sometimes banks of fog roll in off the ocean, pile up against the west side of the range, and build a wall of clouds. In the dry summer they stay there, but in the wet winter, they flow over, spread out, and cast a veil of precipitation over the whole valley. On the western slopes of the Cascades, the Firs, Hemlocks and Cedars drink it up; they love this weather.

The Willamette River’s headwaters are up in these rain-drenched hills at the far southern end of the valley. As it flows north (unusual for a river on this continent), it’s joined by many tributaries, among them the McKenzie, Calapooia, Santiam, and Clackamas, and a over a dozen smaller ones. Some of these are dammed to collect water for irrigation and drinking or to generate electrical power. The Willamette flows into the mighty Columbia, the fifth largest river in North America as measured by discharge, which empties into the Pacific Ocean.

City people see all this landscape mostly from their cars, driving down the I-5 that bisects the valley, or on the big highways that connect the towns and exurbs for commuters. A few folks might venture out onto smaller roads to sip at a vineyard, bird-watch, visit a state park, or hike a trail, and they generally return with positive reports of pastoral beauty. “Oregon wine country” is a tourist destination.

The rural people whose livelihood is connected to agriculture are concerned with the weather, water, agricultural pests, the application of inputs, and—most importantly—finding lucrative markets for their harvests, which is to say, surviving in our competitive system.

Taken as a given by everyone is that the current landscape—geographic, cultural and economic—is “just the way it is.” When everything we see is interpreted through that lens, a significant truth of the landscape goes unnoticed and unremarked upon. In terms of ecology—which is the prime concern of this book—no corner is untouched, no relationship is unaffected, and nothing is “pristine.” This applies not just to the Willamette Valley but to every place on earth, from the depth of the Mariana Trench to the peak of Everest. To understand anything in our contemporary environment—including those species of plants that are labeled “invasive”—we must acknowledge and examine the profound impact of Western civilization.

Lucky for us, our hot air balloon is also a time machine.

Let’s zoom back to 1500 AD, before anyone from the Columbus-initiated European invasion arrived in the Pacific Northwest.

Below us, in the bottomlands, is a mosaic of wetland prairies and forests; a landscape dammed by beavers, grazed by elk, monitored by wolves and shaped by fire. The rivers and streams, rather than being hemmed into narrow, single courses by surrounding fields and roads, are multi-channelled braids meandering in wide curves, slowly flowing from one beaver pond to another.

The prairies are dominated by Bunch Grasses, Sedges and Rushes. Among them are many wildflowers and shrubs including Checker Mallow, Dogbane, Downingia, Lomatium, Milkweed, Popcorn Flowers, Wild Strawberry, Springbank Clover, Buttercups, Spirea, Snowberry and Nootka Rose. Large areas are dominated by blue-flowered Camas in the springtime.

The riverine forests are mostly deciduous—Willow, Alder, Ash, Cottonwood, and Big Leaf Maple, with some Oak and Fir in drier places. In the understory are shrubs or small trees like Red-osier Dogwood, Ninebark, Indian Plum, Vine Maple, Hazelnut, Red Elderberry and Cascara Sagrada, and wildflowers like Delphinium, Columbine, Miners Lettuce, Bleeding Heart and Trillium.

Where the land rises above the pools and rivulets, and into the lower hills there is oak savanna: a grassy woodland with mature Oaks on wide spacings. Growing among the tufts of bunchgrass are Manzanita, Ceanothus, Hounds Tongue, Clarkia, Firecracker Flower, Shooting Star, Fawn Lily, California Poppy, Irises, Honeysuckle, white Asters, Goldenrod, Mules Ears, Bittercress and Golden Paintbrush.

Higher still in elevation, in the upper foothills, is coniferous forest made up of Douglas-fir, Grand Fir, Hemlock, and a few Red Cedars with an understory of Sword Fern, Oregon Grape, False Solomon’s Seal, Huckleberry, Whortleberry, Thimbleberry, Oxalis, Pipsissewa and Creeping Dogwood.

After disturbances like landslides in the drier parts of the valley we see Lupine, Phacelia, Milkweed, Coyote Brush, Oregon Sunshine, Gilia, Sedums, and Douglas Aster.

Humans are also present throughout the valley, who we now call the Kalapuya. They have permanent winter habitations, but have seasonal rounds in the warmer months to harvest Camas, Wapato, and Cattails from the wet prairies, Brodiaea, Wild Onions, Mariposa Lilies, Tarweed seeds, and Hazelnuts from the drier prairies, Blackberries, Thimbleberries and Salmonberries from the riverine forests, Acorns from the Oak savannas, Huckleberries from the Douglas-fir forests, and medicinal herbs from all ecosystem types. They also hunt or catch various animals including Elk, Deer, smaller mammals, waterfowl, fish, crustaceans, and grasshoppers. Salmon can’t make it up the river past Willamette Falls on the lower reaches, so they don’t play the central role in the Kalapuya diet as they do for tribes living along the nearby Columbia River.

The Kalapuya are not agricultural, but intentionally set fires to encourage the abundance of many of their food plants. Plants that respond positively to low-intensity fire include Camas, Bracken Fern, Biscuit Root, Hazelnuts, and many berries. Fire increases the quantity of food plants in forests by making forests more open, and of prairies by preventing trees from moving in. These environmental changes also favor hunting because they promote plants that herbivores eat and keep lines of sight clear. Fire is especially important in oak savanna, where it excludes Firs and holds down the population of acorn-eating weevils. Intriguingly, the only thing that the Kalapuya purposefully plant garden-style is a wild Tobacco, which thrives in the ash of freshly burnt areas. This land management style was dubbed “pyroculture” by Oregon archaeologist, Leland Gilsen.ⁱⁱ

This picture—an abundant, fire-tended foodscape from Beaver-engineered valley floor to tree-lined ridgetop—is a rough approximation of the Willamette Valley when all the plants were “native.” Which species grew where resulted from a web of interactions among animals, other plants, humans, soil and water. That is, the belongingness of these plants in this region was about more than the attributes of climate, seasonality, elevation, etc., of the region, though those factors are of fundamental importance. Put another way, for plants, it’s not just about the where of place but the how of place.

This becomes obvious when we let our time machine scan forward and see what happens with the arrival of Europeans. First come the trappers in the 1700s, who set upon the beavers because their pelts are popular for making hats “back East.” In the mid-1800s, pioneers start arriving en masse, and force treaties on the Native Americans to push them out of the valley and into reservations. The wetlands are drained and the prairies tilled under for agriculture. The forests are cut for timber. The indigenous fires are ceased and lightning-fires are suppressed. The waterways are constricted and channelized, disrupting the floodplains and the seasonal cycles of water table recharging and nutrient deposition.

By the mid-20th century, virtually every acre of the valley has been altered. Conversion to agriculture and urbanization, lack of fire, intensely altered hydrology, and the resulting fragmentation of habitat play holy hell with the plant, animal and human communities of the Willamette Valley, rendering them totally unrecognizable. Of the estimated 400,000 acres of oak savanna pre-colonization, less than 5% remains.ⁱⁱⁱ Without fire, they transitioned into closed-canopy forests of Fir, Madrone and Big Leaf Maple. The wetland prairies are even worse hit, suffering a 99.5% loss. In the present day, only 1% of the Valley is “protected” and only 2% of the land outside those areas is in a condition considered “natural habitat.”^iv The degree of loss is staggering and at this point unmeasurable. For example, as a 1995 Nature Conservancy report put it: “since no high quality remnants of mesic bottomland prairie are known to exist, the species composition of this community is unknown.”^v

Over one million acres of land in the Willamette Valley is dedicated to agriculture.^vi It is within this context that we must place discussions of non-native plants and their impacts. The Canola, Camelina, Mustard, Flax, Clover, Wheat, Hops, Grapes, Peppermint, Hazelnuts, Christmas trees, landscaping plants, market vegetables, and grass seed that monopolize the vast majority of the valley—from the river’s headwaters to the Columbia, from the Coast Range to the Cascades—are non-native, but none are considered, “invasive.” That term is reserved for some of the “weeds” that come up in the ditches between the drained and leveled fields, or along the scraped and graded highways, or in the cattle-stomped pastures of European turf grass, or among the sad stumps of forest clear-cuts, or in cracks in city sidewalks.

The story of the Willamette Valley is not at all unique in the United States—or for that matter in the rest of North America or in South America or Australia or any of the other places colonized by Europeans post-Columbus. Focusing on the US, though, whether it’s the British spreading from New England and Virginia or the Spanish from Florida and California, the story is the same: humans invaded, and some plants happened to follow. The plants did not lead. They took advantage of the disturbances incurred by the invasion, disturbances that in some cases were of types they had already spent millennia becoming adapted to in Europe or Asia: the disturbance of the plowed field, the irrigation ditch, the paved roadside, the chopped down forest, or an urban setting. In the present, plants are adapting to agricultural run-off, mining waste, and herbicides.

Lupinus, commonly known as “Lupine,” is a genus of plants with species native to North America, South America, Europe, Africa and the Middle East. “Texas Blue Bonnet” is a famous one. Lupinus is Latin for “wolf” and the plant was given that name in Europe by people who noticed that it thrived on “poor soils”—meaning soils that are low in nutrients and badly suited for agriculture—because these people believe that, just as a wolf preys on livestock from herds or flocks, Lupine was stealing from the soil. In actuality, Lupine is doing no such thing, and is in fact enriching the soil because, like many plants in its family, it is a nitrogen fixer. In cooperation with underground bacteria, Lupine pulls the element from the air and collects it in nodules on its roots. Naming it Lupinus was a classic case of mistaking correlation for causation, a mistake compounded by the lack of comprehension for how it was actually helping.

Contemporary people can look back at those medieval folks and tut-tut their ignorance. But we, the authors, believe that contemporary people are making essentially the same error now in labeling particular plant species as “invasive”; we too are capable of mistaking correlation for causation, follower for leader, or passenger for driver.

We will return to our time traveling hot air balloon twice more: once to go deeper into the past, and then into the future...