Americans should be proud of their accomplishments in soil conservation: A tale of two regions

Abstract

Over the past 30 or so years, Americans have been subjected to dire assessments of current soil erosion (Trimble and Crosson 2000). Dirt, an interesting new book by David Montgomery, is more objective and moderate, but it still leaves a somewhat negative slant in that one would not know just how much improvements have occurred in the United States. For example, the book includes a map of the Southern Piedmont showing that it lost an average of 18 cm (7 in) of soil to historical erosion. While that's true, what he doesn't tell us is that most of that soil had eroded by the early 20th century and that erosion there has been arrested relative to the 19th century. Another region barely mentioned in passing by Montgomery is the Northern Mississippi Valley Loess Hills (Driftless Area). Settled in the1850s, erosion there was so rampant in the early 20th century that some stream valleys were being buried at rates averaging 15 cm (6 in) per year. Roads, bridges, mills, houses, farms, even villages, were sometimes buried or made unusable within a few years. Tributary stream channels were often eroded to several times their original cross-sectional area, furnishing even more sediment to …