Another illustration: “I need a thin sheet of material that we can wrap around a house just before we apply shingles, siding, or bricks. It needs to have a high coefficient of friction; a low coefficient of thermal conduction; and a high coefficient of toughness—so that it won’t rip as we wrap the house. Oh—and it also must be impervious to moisture.” This isn’t a job, it’s a technical specification. It gives me the choice of buying Tyvek by DuPont, or to be cheap, ignore the spec, and use nothing instead.
I need to go up to a higher level of abstraction in order to discover a job. This is what we might find as we explore for it:
“We’re building a new house here in Boston, where the cold, damp air of winter and the hot, humid air of summer both easily penetrate walls. I want my family to feel warm and cozy in my home in the winter—and cool and dry in the summer. I need to insulate the outside walls of this house so I can minimize the costs of heating and air-conditioning”
I could hire wood (paper) pulp and blow it into the space in my walls to do this job. I could also hire rolls of fiberglass insulation and staple it to the studs in the wall. Or I could hire Tyvek by Dupont. And to nail things down even tighter, I could hire Tyvek and rolls of fiberglass together. Or I could plan on compensating with extra sweaters in the winter and throwing open more windows in the summer. Maybe I should buy a couple of dehumidifiers and fans. Or maybe I could just hire Santa Barbara or San Francisco, where Mother Nature has obviated the problem of insulation—and I could move there.
We can see that this is a Job to Be Done and not a technical specification or requirement. We know this because the alternatives of things to hire to get the job done come from very different categories of products and services.
Mary was our neighbor when Don and I were doing our doctorate studies in Corvallis. I’d stayed with her for a few days in late August while I presented a paper on mycorrhizal connections at a conference. Our evening conversations had drifted over backpacking and canoeing routes, books we’d read, movies we’d seen, how Nava was already in eighth grade and Hannah in tenth, and how she hadn’t seen them since kindergarten, and wed visited the whitebark pines in the Oregon Cascades. “Maybe you can show me a Mother Tree,” she’d said, having listened to me jabber about my recent discovery. Mary was a veteran hiker, having grown up in the Sierras of California, and she’d settled in Corvallis to work as an R & D physical chemist after a postdoc in Australia. I told her she could help me figure out which chemicals were moving through the network. She’d been living by herself all these years, focusing on her job of developing inks for inkjet printers and recovering from the car accident that had taken her friend and injured another and left her badly hurt too.
“What are these globs?” Mary asked, pointing to drops of yellow pitch on the bark of the dead lodgepole pines lining the trail.
“Pitch tubes from the mountain pine beetle,” I said, catching my breath in the thin 6,600-foot air. I could barely keep pace, even though her right leg had been screwed together with plates and was a good inch shorter than her left. I pinched off a piece of the resin, hard like old chewing gum, and put it in her hand. “Is that why the pine is dead?” she asked, wisps of blond hair escaping her ponytail, sunglasses secured with a lanyard. I explained that the pine tried to pitch out – eliminate — the beetle when it burrowed into its bark, but the ultimate cause of death was the blue-stain fungus carried into the wood on the bug’s legs. The pathogen spread through the xylem, plugging the cells and cutting off the water coming up from the soil.
“The tree died of thirst,” I said.
“Geez, dying isn’t that straightforward for a tree,” she said, offering me a drink from her water bottle before taking a swig herself “I would never have guessed that.”
We took in all the dead trees, far as we could see, some whose needles were red, others still green. Lupines remained bright purple among the gray stems, and the grouseberry shrubs shone, taking advantage of the unused sunshine and water, their fuchsia berries sweet as raspberry jam. “The beetles kill the old pines, and then fire melts the resin in the cones to release the seeds. That’s why the young lodgepoles grow in dense thickets after a burn.” I put some berries, not much bigger than raindrops, on her palm and pointed to a dump of juvenile pines, saying that these forests used to be patchy a mosaic of differently aged stands, some old, but most too young to support an infestation. “Things are different now,” I said, explaining that suppression of fire had allowed many trees to reach such an old age and large size that their phloem was thick enough to support a teeming brood of larvae. The beetle outbreak had started in northwest British Columbia and spread south to Oregon, with more than 4o million hectares now dead or dying across North America.
Even though the beetle and fungus had coevolved with the pines, the past few decades of fire suppression had created a vast landscape of aging pines ripe for an epic infestation. With winter temperatures no longer dropping to minus thirty degrees Celsius for long enough periods to kill the larvae feeding in the phloem, the finely tuned symbiosis among the species had ruptured. We were in an outbreak of such massive proportion that people in its midst were reeling.
“Are all these trees going to die?” she asked, starting back up the trail, rusty dust powdering her calves, bare arms muscled from bringing in the winter wood, gait long adjusted to the realignment of her bones.
“Some will live, but most will die,” I replied. The pines produced an array of defense compounds – monoterpenes — to inhibit the beetles. I loved that she was worried for these trees too. Sweeping her hand against a dead trunk, she grabbed a handful of red needles for my inspection. “This outbreak is so intense most trees can’t fend off the bugs. They’ve even detected the swarms with satellites,” I said.
She pointed at a small patch of pines with needles deep jade and suggested the future might not be wholly bleak. I agreed, a bit sheepish. The sweep of dead trees throughout the West was disturbing to witness. Some individual pines could increase their defense through a greater production of the monoterpenes, but even so, not many had survived this outbreak. Subalpine firs under the dead pines had put on new growth, though their needles and buds had been chewed by the western spruce budworm, another insect infesting the conifer forests of the West. Still, in spite of the worms burrowing in the buds of the firs and the beetles in the pines, the forest here was anything but dead. Many saplings were in good health, and plants were spreading into the gaps where the dead pie had fallen over, “Survivors should produce new generations better adapted to pith out the be said. I needed to take a longer view instead of being so obsessed with the dying trees. Mary took my arm and said, “You’ll see, Suzie, it’ll get better eventually.” She’s right, I thought. Still, things had gone badly off the rails — pines in valleys from the Yukon to California were utterly dead.
“It’s even possible the firs and pines can warn each other about infestations,” I said as we continued along the trail. I explained how Dr. Yuan Yuan Song, a scientist from China, had been working with me to see if firs infected with budworms might warn neighboring pines to prepare themselves. Her query had arrived out of the blue, asking if she could come for a five-month postdoc to test whether the warning system she’d detected among tomato plants in the lab also occurred among coniferous trees in forests. Yuan Yuan had already found that tomato plants communicated their stresses to other nearby tomatoes, and we were both curious if similar signals might occur between trees.
A whiskey jack flew in front of Mary and chuckled quee-oo.
We were on the plateau in under an hour, the subalpine firs dwindling as we wound through meadows of beargrass and volcanic rock. Mary put shiny chunks of obsidian and feathery pieces of pumice into her pack, and she slipped a few into mine. “Nava will like this one, she said, shining it on the hem of her T-shirt. We reached the rim and followed the trail skirting its edge, columns of basalt stretching down cliffs. Clumps of thousand-year-old whitebark pines followed the contour of the escarpment, forming the tree line.
I showed her the five-needle bundles growing on the branches of the whitebark pines, distinguishing them from the fascicles of only two for lodgepole pine.
Whitebark depends on Clark’s nutcrackers to disperse its seeds, whereas lodgepole needs fire to open its cones. As if on cue, a gray-and-black bird swooped from a tree with a cone in its beak and flicked over the lava flow, probably to cache it in a favorite hollow among the rocks, which explained why the whitebarks usually grew in clusters. These two species were in a mutual relationship, the birds dispersing the seeds to fecund soils in return for a stockpile of nutritious meals, having coevolved in the harsh alpine environment, both creatures’ genes rigorously shaped through recombination and mutation, adapting bit by bit to glacially slow changes.
“Are these whitebark pines Mother Trees?” Mary asked, skirting a patch of three wrinkled ones with branches stretching in the direction of the wind. Last night we’d watched Mother Trees Connect the Forest, a short documentary I’d made with a graduate student along with a filmmaker who was also an adjunct professor at the university, and she was trying to compare these subalpine trees to those in a rain forest. I pointed to the tallest one of the bunch and said that Mother Trees are the biggest, oldest ones. I grabbed her hand to duck under its crown, to see if the roots were wrapping around those of its neighbors. Mary gestured toward a spate of seedlings on the edge of the canopy. This copse of trees, their thick roots woven in sprawling runners, were sure to be united by a mycorrhizal network.