India, Sept. 28 -- When the Dust Bowl choked the American prairies in the 1930s, the US government tried something nobody had attempted at that scale before: planting rows of trees across the Great Plains to hold the soil down. According to a study published in Built Heritage, the Prairie States Forestry Project saw more than 200 million trees planted across 33,000 shelterbelts between 1935 and 1942. Roughly 80 years later, many of those same tree lines are still standing on working farms today.

The Dust Bowl was more than just bad weather. Decades of plowing up the native prairie grass had loosened the topsoil, and when the drought came, the wind blew it away in dark, choking clouds. President Franklin D. Roosevelt backed the plan to pl...