When Americans think about the causes of the Great Depression, they tend to gaze back to the stock market crash, imagining panic on Wall Street and apocryphal tales of traders leaping from office windows. But reckless investing was only one factor in the historic downturn. The Depression is also a story of environmental collapse and, in the years that followed, one of healing and renewal.

In the years leading up the Great Depression, farmers on the Great Plains plowed their lands too deeply, leaving themselves vulnerable to punishing droughts and powerful winds that would wither their crops, sweep away their fields and steal their livelihoods. Thus, as President Franklin Delano Roosevelt worked to repair and restrain the banking sector, he also sought to make amends with the land. In his first weeks in office, Roosevelt created the Civilian Conservation Corps, a force of more than 250,000 unemployed, unmarried young men tasked with restoring soil, planting trees, fighting forest fires, building roads and blazing trails.

Between 1933 and 1942, “Roosevelt’s Tree Army,” as the Corps was known, planted an estimated 3 billion trees across the United States. Though Roosevelt couldn’t have foreseen it, that effort would have a sizable impact on climate change. As Americans face worsening droughts, floods and storms fueled by rising temperatures, they might look to resurrect the Corps.

Source: Works Progress Administration

Dollar for dollar, planting trees is one of the best ways to tackle climate change. A tree soaks up heat-trapping carbon pollution and stores it in its leaves and branches. How much carbon pollution varies based on its size, location and species, but according to one estimate, a mature tree of average size can absorb around 50 pounds of carbon dioxide per year. That means the 3 billion trees planted by the Civilian Conservation Corps would have offset the carbon output of roughly 15 million motor vehicles— more than every car, truck and bus currently registered in the state of Florida.

Trees also strengthen the environment in the short term. As Roosevelt explained in a 1935 address, forests are “needed for mitigating extreme climatic fluctuations, holding the soil on the slopes, retaining the moisture in the ground and controlling the equable flow of water in our streams. The forests are the ‘lungs’ of our land, purifying the air and giving fresh strength to our people. Truly, they make the country more livable.”

Men in the Corps could see the results of their handiwork. Newly planted trees slowed soil erosion, expanded tree cover and nourished grazing lands. For workers who came of age during the Dust Bowl, the effect was profound.

“I remember the time growing up in North Carolina, looking up and watching Kansas blow by, the Dust Bowl reaching North Carolina, of course. I also remember fires, floods, drought, erosion, soil gone,” Corps alumnus Harley Jones said in the PBS documentary The Civilian Conservation Corps. “We got to see basically a change, not only in us, but also in the total environment, an improvement, not a deterioration, but a major improvement. No more looking up and watching Kansas pass by.”

Dust storm in Stratford, Texas, 1935. Source: George E. Marsh, NOAA

In addition to reviving U.S. lands, the Corps was a tremendous opportunity for those who enlisted. Workers were paid $30 a month, in addition to receiving food, clothing, medical care and vocational training. Roosevelt was determined to prepare men for jobs in the military or the private sector.

“Most of us, first time to have a toothbrush, first time to have a vaccination, first time to have a daily bath, all these firsts,” Jones said. “Many of our boys couldn’t read or write. So one of the first things that FDR said, ‘They will be taught to read and write. Nobody, no boy will leave our camps illiterate.’”

A modern-day Civilian Conservation Corps could achieve these same goals, reviving nature while preparing workers for jobs in government, the military or clean energy. The Corps would guard against climate change by planting forests to soak up carbon pollution, restoring wetlands to protect coastlines against rising seas, and clearing roads to prevent the spread of wildfires.

A Civilian Conservation Corps crew clears a road in the Boise National Forest, Idaho. Source: United States Forest Service via Oregon State University

The group might also train young Americans for jobs in renewable energy. Solar installer and wind technician are the fastest-growing jobs in the United States. A modern-day Conservation Corps might install solar panels and wind turbines on public lands and government buildings, training young Americans for jobs in clean energy. Workers could be recruited from parts of the country hardest hit by the decline of manufacturing.

In recent years, there have been calls for Congress to revive the Civilian Conservation Corps both to reinvigorate the economy and prepare for climate change. The group was disbanded in 1942 to free up money and manpower for the war effort, but its legacy lives on in forests, farms and national parks, and in the men who grew up in the Corps. For Roosevelt, the health of the land and the health of people were bound together. His ideas haven’t lost a shred of relevance.

“We slashed our forests. We used our soils. We encouraged floods. We over-concentrated our wealth. We disregarded our unemployed — all of this so greatly that we were brought rather suddenly to face the fact that unless we gave thought to the lives of our children and grandchildren, they would no longer be able to live and to improve upon our American way of life,” he said in a 1940 address. “We are at last definitely engaged in the task of conserving the bounties of nature, thinking in the terms of the whole of nature. We are trying at least to attain employment for all who would work and can work, and to provide a greater assurance of security throughout the life of the family.”

Jeremy Deaton writes for Nexus Media, a syndicated newswire covering climate, energy, policy, art and culture. You can follow him @deaton_jeremy.