ALL WHO WANDER

For Want of a Fungus the Squirrel Is Lost—As Are We All

THE TASSEL-EARED SQUIRREL chitters. The goshawk cries. And I ponder, leaning back against the vanilla-scented bark of a ponderosa that sprouted before Columbus sailed or the ancient Puebloans vanished. Here is what I wonder: Did Gifford Pinchot grasp the significance of his obsessive push a century ago to plant the seedling of the Forest Service, which now safeguards more than 11 million acres in Arizona? We celebrate his foresight in this issue, with an anniversary story about the rickety beginnings of an agency that still strains to balance the jostling and jabbing of contending interests-environmentalists, hikers, ranchers, loggers, hawks and squirrels. Did Pinchot know what he had wrought? Do we know even yet? I think not. Just as an example, we still have but barely grasped the strange threesome of the hawk, the pine and the squirrel. But let me back up a bit. Out here in the forest, the ponderosas seem sovereign lords of a tranquil world, indifferent to a squirrel's scurry, a hawk's swoop or a mushroom's sprout. Think again. Think small. Stoop down. Consider the humble pine-root fungus, which contains the whole wide world, folded up tight. The fungus grows on the ponderosa roots, producing both underground truffles and aboveground mushrooms. At first glance it seems a mere parasite. But wait: The fungus pays its way. The fungus helps the roots absorb water and provides such essential nutrients that the drought-tolerant ponderosas could not survive without its fungus friend, according to research conducted by Northern Arizona University biologist Jack Sterling States. But the fungus has a problem. How can it spread to each new seedling to serve as a fungal nanny? Enter the tassel-eared or Abert's squirrel. Squirrels love the fungus and its truffle "fruit." They can sniff out a truffle beneath a foot of snow, so the fungus sustains them during crucial portions of the year. Moreover, the truffles supply minerals and nutrients so essential to the squirrels' survival that they only live in ponderosa pine forests harboring certain kinds of root fungi. Perhaps the truffles even help the squirrels digest the tough pine seeds and the cellulose in the tree's inner bark. In any case, something in the fungus is essential to the squirrel. So the squirrel sounds like a hungry fungus parasite. Except for one thing. The squirrels spread fungus spores as they dig in the forest floor. In fact, States found that only the spores he extracted from squirrel feces would sprout and grow on tree roots. So the ponderosas make possible the fungus that makes possible the squirrels that make possible the fungus that mayhap make possible the trees. But wait. We're not through. Despite their service in spreading fungus spores from root to root, the squirrels eat so many pinecones, needles and even bark that they'd be hard on the trees if their numbers got too high. Enter the goshawks. Goshawks live mostly on tassel-eared squirrels. Perch hunters, they thrive under the forest canopy, but can't compete in the open against hawks that circle overhead looking for prey. So logging that has eliminated most old-growth forests has also hammered the goshawks, which are now endangered. How then might the loss of the goshawks affect the squirrels and the fungus and the trees? Of course, being human beings we jostle and jab-wanting to both turn the trees into 2-by-4s and savor the rustle of needles in an oldgrowth forest. So we both bemoan and berate the endangered goshawk. Perhaps it is in our nature, as it is natural for the squirrels to gobble the seeds of the trees that shelter them. But leafing through the stunning photographs in this issue of the places we've protected, I sniff the damp, earthy connections that link the fungus, to the ponderosa, to the squirrel, to the goshawk to Pinchot's politics. And I am perhaps unreasonably hopeful that we may yet attain the wisdom of the fungus, which feeds the squirrel that spreads the spore that nurtures the tree that harbors them all-even the goshawk, waiting with patient claw.