Built to Burn - Design with the Desert: Conservation and Sustainable Development - page 213

Breadth of fire in the Southwest (1700-1993)

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FIGURE 11.2
Until the end of the nineteenth century, fires ebbed and flowed with climatic tides. Then, overgrazing,
the removal of indigenous burners, and active fire suppression—all a product of settlement powered by
industrialization—caused a full-blown recession. The graph shows the breadth of sites holding fire-scarred
trees. (Data from Laboratory of Tree-Ring Research, University of Arizona.)

This pyric geography bent when Europeans and their American offspring arrived, and
by the 1870s it was breaking. The newcomers reintroduced megafauna in the form of sheep,
cattle, and horses, which slow-combusted with their metabolism what open burning had
fast-combusted. Once overgrazing set in, they stripped the primary fuels that had carried
flame (see Chapter 10). The newcomers also removed the aboriginal fire-starters through
war, relocation, and introduced disease; a prominent source of chronic ignition vanished
with them. Beginning in the 1890s, they then set aside vast chunks of the land as forest
reserves that had as a primary charge to remove fire of all sorts. This change in fire's regime
changed also the regimes of earth, water, and air. As Aldo Leopold wrote in 1924, “When
the cattle came, the grass went, the fires diminished, and erosion began”. 4
Fire receded, then collapsed, paradoxically creating an ecological insurgency that has
grown uncontrollably over the past few decades (Figure 11.2). Fire's ecological power was
as great withdrawn as it was applied. Initially this was not obvious: observers saw only an
ebb of flame, which for them measured the success of their ecological stewardship. They
did not appreciate that humanity's role as keep of the flame applied to landscapes as well
as to hearths. They converted their technology and combustion economy to one based on
burning fossil biomass, and used those internal-combustion fire engines to help hold the
line against free-burning flame.
And for decades the consequences remained unseen. Then, stoked by combustibles that
were no longer routinely flushed away by frequent burning, big fires returned (Figure 11.3).
But both feral fire and lost fire were a phenomenon of distant wildlands. Then people
decided to move their cities against and into those wildlands. The result has created a
visible fire crisis to match the invisible one sequestered in the woods and brush.
The big picture is easy enough to grasp. For several decades Americans have been
recolonizing their once rural lands. Satellite photos of settlement in Breckenridge,
Colorado, look surprisingly like those from Rhondonia in southwestern Amazonia. The
American newcomers, however, do not live off the land, only on it. They do not graze,
prune, plow, slash, plant, or burn. They come from cities and carve small exurban enclaves
out of abandoned farmland or platted ranchettes (see Chapter 10). In the eastern United
States, the outcome dapples the countryside with patches of subdivisions and woods,
cloying perhaps but not intrinsically volatile. They are routinely blasted by wind and
water, with vast damages—the ice storms of 2003, for example, acting like a kind of frozen