Squaring the Golden Triangle
J. Agee photo
During the 20th century several techniques have evolved for dryland cultivation. One of those is strip farming, in which a field is divided into strips of equal width, with alternate strips permitted to lie fallow--that is, plowed but unseeded--for one or two years in order to store up moisture. Windblown topsoil from the fallow strips collects in the adjacent planted strips. The result is the crisp geometry of fields throughout the northern plains in the western United States and Canada. Some of the high-tech tractors used to cultivate these mile-long strips are guided by laser-beam devices, but the experienced farmer does it by eye and by feel.