<P> In many regions, more than 75% of the topsoil was blown away by the end of the 1930s . Land degradation varied widely . Aside from the short - term economic consequences caused by erosion, there were severe long - term economic consequences caused by the Dust Bowl . </P> <P> By 1940, counties that had experienced the most significant levels of erosion had a greater decline in agricultural land values . The per - acre value of farmland declined by 28% in high - erosion counties and 17% in medium - erosion counties, relative to land value changes in low - erosion counties . Even over the long - term, the agricultural value of the land often failed to recover to pre-Dust Bowl levels . In highly eroded areas, less than 25% of the original agricultural losses were recovered . The economy adjusted predominantly through large relative population declines in more - eroded counties, both during the 1930s and through the 1950s . </P> <P> The economic effects persisted, in part, because of farmers' failure to switch to more appropriate crops for highly eroded areas . Because the amount of topsoil had been reduced, it would have been more productive to shift from crops and wheat to animals and hay . During the Depression and through at least the 1950s, there was limited relative adjustment of farmland away from activities that became less productive in more - eroded counties . </P> <P> Some of the failure to shift to more productive agricultural products may be related to ignorance about the benefits of changing land use . A second explanation is a lack of availability of credit, caused by the high rate of failure of banks in the Plains states . Because banks failed in the Dust Bowl region at a higher rate than elsewhere, farmers could not get the credit they needed to buy capital to shift crop production . In addition, profit margins in either animals or hay were still minimal, and farmers had little incentive in the beginning to change their crops . </P>

What did the dust bowl cause farmers and land owners to do