More on this book
Community
Kindle Notes & Highlights
There is a necessary wisdom in the give-and-take of nature—its quiet agreements and search for balance. There is an extraordinary generosity.
This is not a book about how we can save the trees. This is a book about how the trees might save us.
Snow lay deeper than a grave nine months of the year here in the mountains.
Those dead cottonwoods along the riverbank in my childhood had fallen and sprouted mushrooms along their thin, cracking skin. Within a few years, the spongy fibers of decayed wood had completely disappeared into the ground. These fungi had evolved a way to break down wood by exuding acids and enzymes and using their cells to absorb the wood’s energy and nutrients.
A rain cloud started to spit, soaking my jeans. Drops beaded on the oilskin of my scruffy jacket.
Maybe Suillus was a friend of the roots, not a decomposer of dead things as Mycena was? My instinct has always been to listen to what living things are saying. We think that most important clues are large, but the world loves to remind us that they can be beautifully small.
I’d never seen such a rich bouquet of fungus—certainly not this brilliant a yellow, plus white and pink too—each color wrapped around a separate tip, bearded with gossamer. Roots need to reach far and in awkward spaces for nutrients. But why were so many fungal threads not only sprouting from the root tips but blazing with a palette like this? Was each color a different fungal species? Did each do a different job in the soil?
spruce wood is more valuable. It’s tightly grained, resistant to decay, and coveted for high-grade lumber. Mature subalpine-fir timber is weak and punky.
white-barked birch tree. The humus there was sweetest because this luxurious broadleaf tree exuded sugary sap and shed copious nutrient-rich leaves each fall.
There were many ways to improve—sow more locally adapted seed in the nursery, grow bigger seedlings, prepare the ground more meticulously, plant sooner after logging, remove competing brush. But the clues told me the answer lay in the soil and how the seedlings’ roots connected to it.
Douglas fir and ponderosa pine were both better than the spruce and subalpine fir at minimizing water loss, helping them cope with the drought.
and nutrients from the soil in exchange for sugars made through photosynthesis from their plant partners. A two-way exchange. A mutualism.
foresters ignored the mycorrhizas, or—worse—killed them with fertilizer and irrigation in the seedling nursery, and focused only on those fungi that damaged or killed big trees, the pathogens. Those parasitic fungal species that infected roots and stems, damaged wood, and sometimes killed trees.
The root tips of the healthy seedlings were covered in webs of colorful fungi, helping them acquire nutrients dissolved in water
What is it about pushing our limits that makes us stronger? How does suffering strengthen the relationships that hold us together?
The arbuscular mycorrhizal fungi of grasses only grow inside the root cells. They’re invisible. Not like the ectomycorrhizal fungi, which grow on the outside of the root cells of trees and shrubs, like tuques.
Lodgepole-pine cones only open when the resin holding shut the scales starts to melt. These mountain forests burn every hundred years because of the cool but dry climate and frequent lightning strikes, combusting the whole stand and consuming the overstory. The scattered alders help replenish the nitrogen gassed out by the wildfire. They do this by supporting special symbiotic bacteria in their roots that convert the nitrogen gas back into forms that the plants and trees can use. In the absence of recurring fire, the light-loving pines would naturally die out in a hundred years, and
...more
ghost pipe plant that parasitizes green plants because it has no chlorophyll itself.
Grizzlies are known for their poor eyesight.
The roots of the lichens—the rhizines—exuded enzymes to break down rock, while the lichens’ bodies contributed organic material, and together they made humus for plants to root and grow.
“Grannie Winnie would know how to grow a garden here if she had to,” I said. Mum laughed. Her mother could grow something from almost nothing. She just needed seeds, compost, and water. “It’s like teaching kids to read,” she said. “Give them the basics, and bit by bit, they will learn.”
“free-to-grow plantations,”
A policy that had grown from the influence of more intensive American practices that increasingly treated forests as tree farms. And here I was talking about seedlings needing to grow near huckleberries and alders and willows.
I was in charge of an experiment that required me to kill plants, creating yet another type of displacement. My task suddenly felt contrary to all my aims.
But the planted seedlings were growing only a half centimeter per year, far less than necessary to meet future harvest expectations. Many had died, and the clear-cut had been declared “not satisfactorily restocked.” To fix this problem, the company foresters planned to spray herbicides to kill the overtopping shrubs, thereby “releasing” the remaining planted prickly spruce seedlings so they could have all the light, water, and nutrients to themselves.
The idea for forest plantations was that killing the leafy plants would free the seedlings from competition, and the companies could then meet their legal obligations for “free-to-grow” stocking.
To see if killing the non-cash-crop plants did indeed create a free-growing plantation that was healthier and more productive than if the natives were left to flourish.
At the lowest dose, most of the plants were still alive, but injured and suffering. The stems of the shrubs that had been cut were already sprouting back and overtopping the seedlings. The best treatment for making a free-to-grow plantation turned out to be the maximum dose of poison.
The herbicide wasn’t supposed to harm birds or animals, because the poison targeted the enzyme only the herbs and shrubs produced to develop protein. But the mushrooms had shriveled and died.
the quicker the pesky native trees and plants were killed and free to grow achieved, the sooner the company’s obligation to tend the plantations would be met.
It didn’t matter that the plants provided nests for birds and food for squirrels, hiding cover for deer and shelter for bear cubs, or that they added nutrients to the soil and prevented erosion—they simply had to go.
the thinking was clear and simple. Get rid of the competition. Once the light, water, and nutrients were freed up by obliterating the native plants, the lucrative conifers would suck them up and grow as fast as a redwood. A zero-sum game. Winners take all.
In the case of birch, killing it improved the growth of some of the firs but caused even more to die—the opposite of expectations. When the birch roots had become stressed by the hacking and spraying, they had been unable to resist the Armillaria pathogenic fungus living naturally in the soil.
Where white-barked birch was left untouched in the control plots, and continued to grow intermingled with the conifers, however, the pathogen remained subdued in the soil. It was as though the birch were fostering an environment where the pathogen existed in homeostasis with the other soil organisms.
The three species of conifers differed in how much birch shade they could grow under, from very little for the star-needled larch, to lots for braided cedar, and somewhere in between for bottlebrush fir. This alone suggested that the best mixtures would vary with each species.
trees and plants could somehow perceive how close their neighbors were—and even who their neighbors were. Pine seedlings between sprawling, nitrogen-fixing alders could spread their branches farther than if they were hunkered under a thick cover of fireweed. Spruce germinants grew beautifully nestled right up to the wintergreens and plantains but kept a wide berth around the cow parsnips. Firs and cedars loved a moderate cover of birch but shrank when a dense cover of thimbleberry also grew overhead. Larch, on the other hand, needed a sparse neighborhood of paper birches for the best growth
...more
grant didn’t cover the installation of a cattle guard, so I painted a fake one across the road at the site entrance. I’d heard that cows don’t cross lines on a road for fear they’ll break their legs. It worked—for the first few months.
The seedlings starved to death because the kind of mycorrhizal fungi they needed had been replaced by the kind only the damned grasses liked. It dawned on me that the rancher had helped me get at my deepest question: Is connection to the right kind of soil fungi crucial for the health of trees?
The seedlings planted in the old-growth soil were thriving. As predicted, the seedlings without transferred soil, or with the dead, radiated transferred soil, were dead.
Merde! The root tips were covered with a dazzling array of different fungi. Yellow, white, pink, purple, beige, black, gray, cream, you name it. It was about the soil.
I’d figured out that accidently killing the mycorrhizal fungi also killed trees. Turning to the native plants for their humus, and putting the fungi in the humus
back into the plantation’s soil, helped the trees.
I decided to conduct an experiment to test whether alder was a real pine killer, as believed by the policies, or whether alder improved the soil with nitrogen and gave pine a boost. My bets were on the latter.
seedlings separately from that of the alder. Alder was considered the main enemy, but the short plants were known to be fighters too. Oddly enough, only fireweed was a true herb, whereas pinegrass was obviously a grass, and huckleberry and thimbleberry were shrubs, but all were shorter than my knees, and so I lumped them together in what I called the “herbaceous layer.” To evaluate the competitive effect of the herbaceous layer, I’d create three separate alder-free herbaceous treatments: 100 percent herb cover, where I’d leave the natural cover of herbs to grow freely; 50 percent herb cover,
...more
Alders, pines, and herbs all required water to carry out photosynthesis, but the alders needed the most in order to make enough energy to transform (fix) atmospheric nitrogen to ammonium, which the alders could then use.
During the day, water pressure in the xylem should be low as the roots struggle to pull water from the drying soil to meet the vapor deficit created by transpiration. The xylem pressure reading at night should be higher because the stomata are shut and the taproots are still accessing the ground water, leaving the xylem saturated and not under any water stress.
What would the long view—and the complexity added by the vital need for nitrogen—prove?
By late August, the neutron probe showed the soil under dense alder had filled with water again. There was now—already—as much water in the dense-alder treatments as in the bare-earth patches. Not only were the soil pores refilling with late summer rains and dewdrops, they were being inundated with groundwater at night, when the alder taproots pulled water from deep in the soil and exuded it through lateral roots into the dry surface soil in a process called hydraulic redistribution. Water rerouting.
And something else was happening in that denuded, pine-seedling-only soil. When the raindrops hit it, the water ran off the surface, carrying tiny particles of soil with it. Silt, clay, and humus grains got transported away in rivulets because there were no living leaves or roots to stop them. As the alder-dense plots began gaining water from late August and over the next few months, the bare earth started losing it.
It turned out that getting rid of alder so pines could be free to grow provided only a fleeting advantage in water uptake. All this killing was starting to look a lot like overkill. Not only that, its side effect was a loss of soil.
