farming methods necessitate early fall breaking in order to prepare the land to receive and store as much as possible of the hoped-for fall and winter rains. During periods of drought these rains fail 15 wholly or in part to materialize, in their stead appearing sweeping dry northers which pick up the loose soil, filling the atmosphere with a choking cloud of dust which is spread southward, some of it far out over the Gulf of Mexico. The winters of 1933-34, 1934-35, and 1935-36, particularly the second, saw a dry phase of the weather cycle during which the soil of ploughed ground was blown away down to the shear-plane of the plow point; and the region became popularly known as the "Dust Bowl." Restoration of its native buffalo- and grama-grass cover seems the only logical hope of pre venting disastrous recurrences of these dust storms; continued cultivation seems certainly to assure such recurrences.
15 Thornthwaite, C. W., 1936, "The Great Plains," in "Migration and Economic Opportunity," University of Pennsylvania Press, Chap. ?, pp. 202 -250, 11 figs., 1 pi.
Benjamin Carroll Tharp