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Page 232


The fact remains, however, that the Bonitians lived a long while
in Chaco Canyon and that farming was their livelihood. Lacking a
living stream, they necessarily depended upon floodwaters for irrigation.
Bryan believed that the best agricultural lands available to them
were the alluvial fans at the mouths of the rincons. But scattered
areas in midvalley were also favorable—the sandy borders of discontinuous
channels and places where water temporarily ponded.
Experience dictates the selection of such places.

Inherited knowledge and understanding of soils and drainage are
prerequisites in the choice of areas suitable for floodwater farming.
Those overflowed by slow-moving floodwaters are everywhere preferred
areas. The flow must wet the ground without uprooting plants
or smothering them under washed-in sand. It is the freshly deposited
film of sandy silt that renews these floodwater fields. Hence the
operator must know how to gage the amount of runoff and check
erosion; he must anticipate the muddy onrush and stay on the job
until it has passed, according to the most successful Navaho farmer
we visited in the Chaco area (Judd, 1954, p. 55).

As a result of his study of local topography and following observations
among the Pima, Papago, and other desert tribes, Bryan (1929,
1941, 1954) believed that Chaco Canyon in Bonitian times was eminently
suited for floodwater farming and that it would be equally
suitable today if annual precipitation were what it was formerly and
if there were no modern arroyo.

This present-day arroyo, now 30 feet deep and 100 to 300 feet
wide, presumably began about 1850 and has proved more destructive
than either of its predecessors. If it follows a like cycle it, too,
eventually will fill with transplanted alluvium; additional soil will
blanket the refill and a new ground cover will take root. Indeed, as I
write these lines, those very processes are being expedited by the
National Park Service in a studied program of erosion control that
includes introduction of check dams and the replanting of willows
and cottonwoods. Since stockmen have moved their herds elsewhere
and Navaho sheep and goats are restricted, it should be possible once
again to reestablish a green carpet lengthwise of Chaco Canyon, but
the pine forests that furnished timbers for Pueblo Bonito and its
neighbors cannot be reclaimed.