Years later, virtually all of the trees that survived their first few years in the pasture finally began to get broad enough to start shading out the grass below. It will still be many years before the canopy closes in the pasture and the grasses begin to be replaced with shade-loving forest herbs, shrubs, and ferns. But now, the seedlings’ roots are thick and broad enough to provide a strong foundation and win the competition for soil nutrients and water. We no longer have to maintain the restoration; it maintains itself. At the tipping point when the saplings begin to win and the grasses and invasives begin to lose, restorationists say, “The trees are free to grow.”
I like that phrase. It’s a goal in land stewardship that’s parallel to the goal Susan and I had as parents. We wanted to raise our boys, like these trees, so they got to that tipping point and no longer needed our care. Thereafter, they were strong and independent. They were free to grow.
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As we walk through the restoration in the evening, checking on the trees, Susan has the habit of touching each one as we go by. She isn’t even aware; she just touches them. And we comment as we pass: “Wow, this Doug-fir is taking off. . . . Too bad—this cedar just died. . . . We should add a couple hemlocks here. . . . I wonder if grand firs would work in this area. . . . Look where a black-tailed buck has been jousting with this willow, rubbing velvet off. . . . Weevils are killing the tips of this spruce.”
We were doing this once when Susan’s father was visiting. Carl was eighty-four at the time, and as we weaved around the saplings, talking and commenting in the sunset light, he exclaimed to no one in particular: “This is just what we did sixty years ago. It’s just what we did.”
A Working Forest
Carl Leopold died on November 18, 2009. He’d spent more than sixty years working as a research scientist—a plant physiologist who studied how plant hormones function and how seeds survive extreme drying and long periods of dormancy. He planted trees wherever he lived and was a founding director of the Tropical Forestry Initiative, the Finger Lakes Land Trust, and the Aldo Leopold Foundation. At age eighty-nine he was still riding a moped to the office; he worked the day he died.
As a memorial to him we bought a tract of forest near our place at Tarboo Creek. Most of the woods had been clear-cut in 1965 but the corporation that owned it had left large numbers of cedar saplings standing—probably with the idea of selling a “green” clear-cut for development. The development never materialized, so third-growth timber grew. The company pulled out of the Pacific Northwest in the 1970s and sold the parcel to a Danish investor who had been buying up timberland in Oregon and Washington for decades. At the time we bought the land, he was planning to clear-cut the forest, subdivide, and sell lots for development.
Second home and retirement home development has emerged as one of the great threats to open space in the United States. Puget Sound is ringed with view homes, and throughout the United States suburban sprawl has converted millions of acres of working timberland and farms, burned up trillions of dollars in gas, and wasted billions of hours in commuting time—when people could’ve been working or playing with their kids. We wanted the Carl Leopold Forest to offer an alternative.
Intense pressure on farms and forests is building all over the world. When Carl was a teenager, there were about 127 million people in the United States and just shy of 2.2 billion in the world. As I write this, there are almost 324 million people in the United States and more than 7.3 billion on the planet. In 2050, when today’s teenagers will be in their fifties, researchers estimate that world population will be about 9.5 billion. Those projections assume that fertility rates—the average number of children a woman has during her lifetime—will continue to drop from the historical highs that occurred between 1965 and 1970. If fertility rates don’t drop as dramatically as the optimistic projection, the best analyses suggest that world population will be closer to 11 billion by 2050. If this scenario plays out, there will be more than 16 billion people on the planet in the year 2100, when the children of today’s teenagers will be elderly. And if the fertility rates observed today continue into the future—that is, if there’s no further reduction in the global average number of children per woman—there will be more than 28 billion people on Earth in 2100.
We worry now about traffic, the price of food and gas, and whether our kids will be able to afford a house. It’s hard to imagine what the world of 2050 will be like with an additional 2.2 billion or 3.7 billion people. Faced with projections like this, thinking globally can be overwhelming. But acting locally can still be inspiring.
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In the main part of Carl’s forest, the little cedar whips that were spared in the 1965 cut are now 100 feet tall and 3 to 4 feet across where their flaring stems plunge into the ground. For reasons that are a complete mystery to us, there is also a 7-acre stand of big Douglas-fir trees—some of them more than a century old, 175 feet tall, and 4 feet in diameter at breast height. Neither we nor a forester friend can figure out how they avoided getting cut decades ago. The tract also hosts three tributaries to Tarboo Creek that flow for most or all of the year. Two have carved dramatic canyons into the hillside and the other splays into four smaller channels, like fingers from a palm. The ridges between these fingers are littered with huge rotting logs left over from the old-growth days.
Carl’s forest is a memorial, but it is not a preserve. It’s working land—a working forest. In addition to producing sustainable harvests of wood products, we hope to reproduce the four structural characteristics of an old-growth forest.
First, downed woody debris on the forest floor. In old-growth forests, up to 10 percent of the soil surface can be covered with downed wood. The largest constituents are tree trunks that are slowly rotting away. As termites, ants, fungi, and bacteria recycle nutrients and soften the wood, the logs gain the ability to soak up winter rain and store it, spongelike. The moisture helps to keep the roots of nearby living trees moist in late summer and supports the growth of tree seedlings down their length—the nurse-log phenomenon.
Second, standing dead snags. These are stately columns—the ruins of majestic old trees. Snags go through five stages of decay over a span of two hundred years, a little like Shakespeare’s seven stages of life. At an advanced age they have sloughed their bark and branches and stand naked to the world, their tops broken off by windstorms. They are long dead but also full of life, for they’re riddled with cavities that provide warm, dry, secure homes for flying squirrels, bats, owls, and woodpeckers; if they hollow out at the base they also offer denning sites for bears. Almost a hundred species of birds and mammals in the Pacific Northwest use snags; more than half of those species can’t live without them.
Third, some two-hundred-year-old trees. These are the giants we all associate with old growth—great beasts with limbless stems rising hundreds of feet above the forest floor. Their lower branches can be 8 inches or more in diameter and are invariably draped in air plants, or epiphytes. In the tropics, trees are festooned with orchids and bromeliads; in the Pacific Northwest, epiphytes range from pillowlike tufts of moss and sprays of licorice fern to rubbery, leaf-shaped lichens. Near the coast, the broadest and mossiest of those branches are home to one of the last North American bird nests to be discovered and described—that of a little seagoing bird called the marbled murrelet. The big trees are important to people, too. An acquaintance named Laura Solomon from the Lummi Nation near Bellingham, Washington, told me about a stand of old-growth Douglas-fir that she’d been visiting for years but that had been recently logged. “These are our churches,” she said. “Cutting that forest was like destroying a cathedral.”
Fourth, complex structure. By this, scientists mean that from the forest floor to the tips of the largest, canopy-forming trees, there are multiple layers of vegetation. Below the uppermost layer, or canopy, is a stratum consisting of large trees that are still growing toward the tallest “dominants.” Below them are an array of small trees, then shrubs, and f
inally ferns and herbaceous plants on the forest floor. The layers make efficient use of the incoming sunlight, and their presence means that food and places to live are available at a wide array of heights above the ground.
This is the kind of forest that Lewis and Clark found and that Chief Seattle grew up in. It is also one of the most effective habitats in the world in terms of sequestering carbon.
I’ll never forget the first time we took Carl Leopold to see old-growth trees. He looked up in awe at a monumental Sitka spruce and breathed, “Think of all the fixed co2.” When that spruce took up carbon dioxide molecules from the air, fixed them into a sugar molecule during photosynthesis, and used that sugar to manufacture the cellulose and lignin that stiffened a new cell wall in its trunk, it added to what scientists call a carbon sink. Every one of the carbon atoms in that massive tree will stay in place for hundreds of years while it is living and some additional hundreds of years as the trunk and roots slowly decay. Finally, each carbon atom will be released into the atmosphere in the form of co2as bacteria, fungi, and other decomposers exhale.
Recent analyses have debunked the long-standing view that old forests stop accumulating carbon. The conventional wisdom was that as growth slows in stands of old trees, just as much carbon dioxide is released to the atmosphere from decaying dead wood as enters living trees via photosynthesis—meaning that carbon use and carbon release are in a steady state. But it turns out that this view was based on the results of a single study published in 1969. Research over the past forty years in hundreds of sites in temperate and northern latitudes has shown that older forests continue a net accumulation of carbon into old age—up to eight hundred years—and that old growth in the Pacific Northwest contains the most wood, and thus the most carbon, of any forest type measured to date: up to 1,600 cubic meters per hectare.
Ironically, young forests can act as net sources of carbon dioxide, even though the trees may be growing much more rapidly than old-growth trees. A large amount of the carbon in mature forests is stored in the soil as humus or in tree roots. If the mature forest is wiped out by fire or logging and roots begin to decay, the amount of carbon released from the underground reservoir can exceed the amount taken up by the young trees. When this occurs, converting older forests to younger forests produces a net increase in atmospheric carbon dioxide and thus heat-trapping gases. It has a positive feedback effect on global warming.
We’ve already started to let windfall trees in Carl’s forest stay down and insect-killed trees stay up. Friends from Europe are perplexed at this—their forests are clean. Compared to woods in the Old World or an industrial tree farm in the Pacific Northwest, Carl’s forest looks a mess.
Other habitats can be effective carbon sinks as well, but most of them are unpleasant places to spend time unless you’re an anaerobic bacterium. In most areas that function as carbon sinks, organic matter builds up and sequesters carbon because decay is slow—the carbon present in cellulose, lignin, sugars, and other organic compounds isn’t being released back into the atmosphere as co2very quickly. Decay is slow in habitats that are cold, and extremely slow when oxygen is scarce or absent. Today, the major carbon sinks include oxygen-free waters in the bottom of the ocean, peats that form in the Arctic or in bogs, and anaerobic mucks and muds that reek of hydrogen sulfide. These aren’t places you want to go on a first date. A wildflower-strewn prairie—where carbon is being added to the soil by roots growing 10 or even 20 feet underground—or an old-growth forest is an attractive alternative if you want to store your carbon and enjoy it, too.
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When Susan and I moved to the Northwest from Wisconsin in 1985, we arrived to find a war in the woods. Old-growth forests in northern California, Oregon, Washington, and British Columbia had been cut since the mid-to-late 1800s, starting at sea level and working up the slopes of the Cascade and Olympic mountains. By the 1980s, only about 10 percent of the original stands remained in Washington and Oregon, and almost all of the remaining old growth was in national forests. Large-scale replanting of trees had started only in the 1940s and ’50s; the industry’s plan was to cut the remaining old growth in the 1980s and ’90s and buy time for the plantation trees to mature.
This plan ran into a buzz saw of lawsuits filed by environmental organizations. The suits claimed that applications to cut the remaining old growth violated the U.S. Endangered Species Act because they put the northern spotted owl—a bird that relies on old-growth habitat—at risk of further decline. The legal action was successful; it virtually halted the cutting of old growth on public land.
The economic impact was tremendous—at the time, forestry was the Northwest’s largest industry. Job losses were severe because harvesting old growth is labor intensive. The trees have to be cut by a feller with a chainsaw, then limbed and sectioned by hand before they can be loaded onto trucks and transported to the mill. Those jobs disappeared. The old mills, which were set up to handle the gigantic old-growth logs, shut down—sooner than the industry had planned.
When the war was over, the industry had changed dramatically. The inevitable transition to processing second- and third-growth timber happened sooner rather than later. Mills retooled to handle small logs from forty-to-sixty-year-old trees grown on plantations and were reengineered to be almost completely automated. Cutting small second-growth trees also required much less handwork than cutting old growth. In the Tarboo Creek watershed, we’ve seen 60-acre clear-cuts run by two people: one running a feller-buncher—a cutting-and-limbing machine that lumbers along on tractor treads—and a second running a loader with a gigantic claw for picking up trunks and piling them into stacks that can be loaded onto waiting trucks. The pattern of land ownership changed, too. Many of the big private firms turned at least part of their attention to real estate development, selling land with access to power lines for second homes, retirement homes, and hobby farms, or even entire planned exurban communities. And recently, more and more timberland has been bought up by real estate investment trusts, or reits—groups that are betting on a growing human population to furnish long-term demand for forest products. They hold wood-growing land as an asset.
In a sense, the forest products industry in the Northwest has followed a trajectory similar to agriculture in other regions of the United States. Large forest-product companies or reits manage their land to maximize income and productivity—with clear-cuts scheduled on forty-to-fifty-year or even shorter rotations, then replanted to fast-growing cultivars of Douglas-fir. These outfits grow small trees and sell 2-by-6 studs, plywood, chips used in papermaking, and other large-volume, low-priced commodities. It’s a cropping system. Because they own and process their own monocultures, their business model echoes the elements of big agriculture, where specialist corn and soybean growers sell to a few commodity-processing and marketing behemoths, which market to industrial-scale meat producers or fast-food companies buying in enormous volume.
But small landowners, who grow bigger trees and may harvest by selective thinning rather than clear-cutting, also have a role to play. These are family-owned businesses that grow six or more different species and produce bigger logs used in more specialized products like posts, beams, cedar utility poles, flooring, paneling, or knot-free, furniture-quality wood. These small, family-run operations are akin to the new farms that are cropping up near our place in Washington’s Jefferson County. There, a cadre of young and well-educated farmers, orchardists, and food processors are starting successful businesses. They practice a less capital- and more labor-intensive style of farming and produce high-value specialty products: fresh vegetables and organic grains, cheese, free-range chicken and eggs, restaurant-quality beef and pork, hard ciders and fruit brandies, and organic fruits and berries. Most are vertically integrated businesses: they do their own marketing and sell directly to people who want to eat locally produced, high-quality food.
In essence, the ownership of farmland and forests in the United States has followed the old Hamilton-Jefferson
split: a numerically dominant, mercantilist economy is driven by financiers and large corporations, and a relatively tiny agrarian society is run by small family farmers. For more than two hundred years, the Hamiltonians have won almost all of the political and economic battles; government agencies and tax policies are organized around their needs. But the Jeffersonians—the young, innovative farmers and foresters—are still here working the land. And like most dichotomies, the big ag and small ag divide isn’t exclusive. Both have a place in a healthy rural economy and landscape.
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Our goal is to manage Carl’s forest for the long term and produce a steady stream of high-quality wood products. One of our first management efforts toward this objective focused on a 40-acre tract adjacent to the north edge of the older forest. This is a stand on an east-facing slope, bisected by a tributary to Tarboo Creek, that was clear-cut in 1997 and then put up for sale.
At fifteen to twenty years of age, regrowing trees start to form a closed canopy and can benefit enormously from what foresters call a precommercial thin. The adjective means that the thinned trees aren’t sold but simply dropped and left to rot and add organic material to the soil. Our precommercial thin had two goals: giving the most vigorous trees room to grow and maintaining or increasing species diversity. As we moved through this young stand, clad in helmets, Kevlar chaps to prevent the signature chainsaw wound (a deep gash across the thigh), gloves, and ear and eye protection, we were trying to achieve an overall, average spacing between trees based on research regarding how stands respond to different severities of thinning. But after that, we made decisions on the fly. Which stems would live and which would die? Red alder matures much earlier than Douglas-fir, which matures much earlier than western redcedar. In some areas we cut to clump individuals from the same species so they could be harvested together; in others, we actively favored the rarer species to increase overall diversity. We dropped trees that had lost their leaders and were growing twinned stems, and we eliminated trunks that were misshapen—unless the art in their knobby projections and sweeping curves spoke to us.
Saving Tarboo Creek Page 11