The GGW Didn’t Stop Desertification


Photo credit: Smithsonian Magazine

A farmer in southern Zinder, Niger, collects leaves that will feed his sheep. (Chris Reij)

The “Great Green Wall” Didn’t Stop Desertification, but it Evolved Into Something That Might

The multibillion-dollar effort to plant a 4,000-mile-long wall of trees hit some snags along the way, but there’s still hope

It was a simple plan to combat a complex problem. The plan: plant a Great Green Wall of trees 10 miles wide and 4,350 miles long, bisecting a dozen countries from Senegal in the west to Djibouti in the east. The problem: the creeping desertification across Africa.

“The desert is a spreading cancer,” Abdoulaye Wade, Senegal’s president and the wall’s standard bearer, said. “We must fight it. That is why we have decided to join in this titanic battle.”

There were just a few problems.

Planting trees across the Sahel, the arid savanna on the south border of the Sahara Desert, had no chance to succeed. There was little funding. There was no science suggesting it would work. Moreover, the desert was not actually moving south; instead, overuse was denuding the land. Large chunks of the proposed “wall” were uninhabited, meaning no one would be there to care for the saplings.

Soon after Wade began touting the tree planting plan, scientists began dissenting.

“This was a stupid way of restoring land in the Sahel,” says Dennis Garrity, a senior research fellow at the World Agroforestry Centre.

“If all the trees that had been planted in the Sahara since the early 1980s had survived, it would look like Amazonia,” adds Chris Reij, a sustainable land management specialist and senior fellow at the World Resources Institutewho has been working in Africa since 1978. “Essentially 80 percent or more of planted trees have died.”

Reij, Garrity and other scientists working on the ground knew what Wade and other political leaders did not: that farmers in Niger and Burkina Faso, in particular, had discovered a cheap, effective way to regreen the Sahel. They did so by using simple water harvesting techniques and protecting trees that emerged naturally on their farms.

Read the full article: Smithsonian Magazine

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.