In 1891 Gifford Pinchot, later to be appointed America's first Chief Forester by Teddy Roosevelt, visited the Kaweah Colony, a utopian Socialist community situated in a grove of California's Giant Sequoia. As related by Stephen Pyne in Fire in America (p 302):
... Kaweah colonists informed [Pinchot] that they had saved the grove from burning up 29 times in the past 5 years. To this, Pinchot wryly inquired, "Who has saved them during the remaining three or four thousand years of their age?"
Had Pinchot really understood thoroughly the implications of his question, he would have known how to build a forest. More importantly, he would have known how not to build a forest, and the megafires that sweep the Western US (and other parts of the planet) every year would be more controllable and less destructive.
To build something, you usually start by clearing an area and bringing in a construction crew. Ten thousand years ago, across the northern tier of the continent, where millions of acres of forest still stand today, the land had been cleared by and still held remnants of an ice sheet that had been as much as 2 miles thick in places. The construction crew had already arrived somewhere between two thousand to as much as thirty thousand years earlier (estimates vary). Even in unglaciated areas, like the southwest, climate change would displace existing ecosystems and replace them with ecologies adapted to the warmer climate that has ruled for the past ten thousand years, through the efforts of the same contractors.
The construction crew had mostly meager tools - stone axes, obsidian knives, no saws - but they possessed the power tool of their age (and succeeding ages): fire. Fire was an all-purpose tool and its use didn't follow a set of plans or blueprints, but it built forests anyway.
In the Eastern US, pre-Eurosettlement Indians practiced agriculture, but had neither tractors nor livestock for clearing land, nor pesticides, herbicides or fertilizer. Fire could serve all of those purposes.
With no malls, supermarkets, shopping carts or minivans or even horses, food (on the hoof) might be more available at hard-to-traverse higher altitudes. Fire could be used to drive game to lower valleys. But lower valleys might be dense with brush and cover for meat - fire could clear the brush making hunting success more likely. It could even rejuvenate old woody stems as young, tender shoots more palatable to game animals. Fire could be used to drive game into enclosures or over cliffs.
Without bulldozers and heavy equipment, fire could be used to clear paths for travel. Without artillery or land mines, fire could be used to attack an enemy at a distance or deny an enemy cover or hiding places. Without telephone or email, fire could be used to signal at a distance. Without television or fireworks, torching a tree or patch of woods could be dramatic entertainment.
How much and how often and where did Indians burn? Pyne (p 79):
... the modification of the American continent by fire at the hands of Asian immigrants [now called American Indians, Native Americans, or First Nations/People] was the result of repeated, controlled, surface burns on a cycle of one to three years, broken by occasional holocausts from escape fires and periodic conflagrations during times of drought. Even under ideal circumstances, accidents occurred: signal fires escaped and campfires spread, with the result that valuable range was untimely scorched, buffalo driven away, and villages threatened. Burned corpses on the prairie were far from rare. So extensive were the cumulative effects of these modifications that it may be said that the general consequence of the Indian occupation of the New World was to replace forested land with grassland or savannah, or, where the forest persisted, to open it up and free it from underbrush. Most of the impenetrable woods encountered by explorers were in bogs or swamps from which fire was excluded; naturally drained landscape was nearly everywhere burned. Conversely, almost wherever the European went, forests followed. The Great American Forest may be more a product of settlement than a victim of it.
(emphasis added)
Yet the last two sentences make it appear that Europeans built North American forests, not Indians. In reality, the European contribution has been more that of Eurotrash tenants, who occupied the structure built by the original crew, and proceeded to modify and trash it, building shoddy additions in violation of the building and fire codes.
The proof is in the answer to Pinchot's question in the intro to this diary. Who saved the Sequoia over three to four thousand years? The Sequoia did.
As the Indians applied their fire regime - in northern climes, possibly before forests even appeared - the plant community reacted. Some species were obliterated by fire early on, but other species were already adapted to fire and even loved it.
The Sequoia (giant sequoia - Sequoiadendron giganteum) is an interesting example of both of the major types of fire adaptation. You could probably (but don't try this at home) build a campfire of good size right next to a mature Sequoia and not harm it, beyond scorching the bark. The Sequoia has extremely thick bark which insulates and protects the rest of the tree from low intensity fires - the kind that occur when an area burns frequently and fuel doesn't have a chance to accumulate. In the most common ecosystem in the west, Ponderosa pine have thick bark too, from a very young age. The next most common species - Douglas Fir - develops thick bark as it matures. In the east, oaks and elms have similar adaptations, and dominated prairie/savannah/woodland interfaces that burned often.
The other feature of Sequoia's fire adaptation is its reproduction. Sequoia is one of a number of species whose seeds don't open without fire and who opportunistically take advantage of fire's aftermath:
The Giant Sequoias are having difficulty reproducing in their original habitat (and very rarely reproduce in cultivation) due to the seeds only being able to grow successfully in mineral soils in full sunlight, free from competing vegetation. Although the seeds can germinate in moist needle humus in the spring, these seedlings will die as the duff dries in the summer. They therefore require periodic wildfire to clear competing vegetation and soil humus before successful regeneration can occur. Without fire, shade-loving species will crowd out young sequoia seedlings, and sequoia seeds will not germinate.
Lodgepole pine in the west, jack pine in the east and even some shrubs like snowbrush (ceanothus velutins) have the same or similar adaptations.
Some woody shrubs - vine maple, willow, ocean spray (holodiscus discolor) - seem to invite fire. They grow in clumps of many stems, and as the older stems die off, they fall to the outside in a radial pattern producing a leader that acts like a fuse to draw fire into the center of the plant. This spring we cut one willow clump to about 6 inches in height, built a fire over the stumps, and it's now about 6 feet tall and 8 feet wide.
The thick, dense forests we associate with wild lands and a natual state are almost certainly a European creation. You build a healthy forested ecosystem by burning frequently, because the species that populate such an ecosystem have been naturally selected by years of human-induced burning. Alternatively, you can use a surrogate for fire like thinning - a process any successful gardener is familiar with. Forests are gardens writ large.
The way to not build a forest is to begin by excluding fire, or when fire occurs, suppress it as completely and quickly as possible. It might be necessary to remove the indigenous inhabitants - ethnic cleansing or genocide aren't out of the question - to foster the illusion of a pristine, untouched-by-humans realm. Better still, exclude all human intervention. (For example, consider how much firewood Native Americans had to collect from forests to satisfy their heating, cooking and manufacturing needs. Even if they never burned except in campfires, that activity would have removed a huge number of tons of fuel from forests annually.)
As these things usually go, we've invented a name for these tracts of poorly built, poorly maintained, thoroughly trashed forest lands: we call them "wilderness" and have even enshrined their degraded state in legislation - the Wilderness Act of 1964. It precludes any restoration, improvement or maintainance of designated wild lands by human agency. The error is not in setting aside wild lands for habitat or forest to be free of permanent human development - the error is in excluding any human activity at all, even beneficial, necessary activity. That's, as in William Cronon's essay, The Trouble with Wilderness
So while activity increases to restore private lands in intermix (wildland-urban interface) areas and state and National Forests (what Pyne, in Tending Fire: Coping with America's Wildland Fires calls "the Land Between") to their pre-Eurosettlement condition and health, designated wilderness areas go untended and regularly burn in thousands-of-acres chunks annually - not in the beneficial low intensity fires they evolved with and adapted to, but in destructive high intensity fires. Wilderness areas are a grand experiment in ecosystems that never were and may not be for long - they're a departure from what was the 'natural' state between the retreat of the glaciers and the arrival of Europeans, the natural state being a human constructed and maintained ecosystem of remarkable sustainability. And as Pyne notes:
Let the restorationists savor the irony if, years hence, the legally wild has lost much of its biodiversity or melted into a biotic lump, while the unremarkable Land Between blooms with ecological splendor.
(Pyne, Tending Fire, p 163)
and parenthetically:
(So fixated are some critics on hindering misuse that they would ban legitimate uses as well. Fearful, for example, that good forest thinning and burning might lead to bad, they would rather ban the practice altogether)
(Pyne, Tending Fire, p 171)
It's something to think about the next you time you celebrate or advocate wilderness. There are two essential questions: What is the acceptable range of conditions for this place 50 or 100 years from now? And what's the science behind achieving and maintaining those conditions?