National Geographic : 2014 Oct
54 national geographic • october 2014 it also helps cut down on pests. The farmers here are learning to plant strategically, setting out rows of Tithonia diversifolia, a wild sunflower that whiteflies prefer, to draw the pests away from the cassavas. The use of compost instead of synthetic fertilizers has improved the soil so much that one of the farmers, Pius Paulini, has doubled his spinach production. Runoff from his fields no longer contaminates streams that supply Morogoro’s water. Perhaps the most life-altering result of or- ganic farming has been the liberation from debt. Even with government subsidies, it costs 500,000 Tanzanian shillings, more than $300, to buy enough fertilizer and pesticide to treat a single acre—a crippling expense in a country where the annual per capita income is less than $1,600. “Before, when we had to buy fertilizer, we had no money left over to send our children to school,” says Kibwana. Her oldest daughter has now finished high school. And the farms are more productive too. “Most of the food in our markets is from small farmers,” says Maro. “ They feed our nation.” When I ask Maro if genetically modified seeds might also help those farmers, she’s skeptical. “It’s not realistic,” she says. How could they af- ford the seeds when they can’t even afford fer- tilizer? How likely is it, she asks, in a country where few farmers ever see a government ag- ricultural adviser, or are even aware of the dis- eases threatening their crops, that they’ll get the support they need to grow GM crops properly? From Kibwana’s porch we have sweeping views of richly cultivated terraced slopes—but also of slopes scarred by the brown, eroded fields of nonorganic farmers, most of whom don’t build terraces to retain their precious soil. Kibwana and Paulini say their own success has attracted the attention of their neighbors. Organic farm- ing is spreading here. But it’s spreading slowly. That’s the central problem, I thought as I left Tanzania: getting knowledge that works from organizations like SAT or IRRI to people like Juma. It’s not choosing one type of knowledge— low-tech versus high-tech, organic versus GM— once and for all. There’s more than one way to increase yields or to stop a whitefly. “Organic farming can be the right approach in some areas,” says Monsanto executive Mark Edge. “By no means do we think that GM crops are the solution for all the problems in Africa.” Since the first green revolution, says Robert Zeigler, eco- logical science has advanced along with genetics. IRRI uses those advances too. “You see the egrets flying out there?” he asks toward the end of our conversation. Outside his office a flock is descending on the green paddies; the mountains beyond glow with evening light. “In the early ’90s you didn’t see birds here. The pesticides we used killed the birds and snails and everything else. Then we invested a lot to understand the ecological structures of rice paddies. You have these complex webs, and if you disrupt them, you have pest outbreaks. We learned that in the vast majority of cases, you don’t need pesticides. Rice is a tough plant. You can build resistance into it. We now have a rich ecology here, and our yields haven’t dropped. “At certain times of the day we get a hundred or so of those egrets. It’s really uplifting to see. Things can get better.” j The central problem isn’t choosing low-tech or high-tech. It’s getting knowledge that works to people like Juma. The End of the Florida Orange? This year’s Florida orange crop may be 20 percent smaller than last year’s. The culprit is citrus greening, a fatal bacterial infection spread by invasive Asian psyllids to almost all of the state’s groves. One way to combat the problem involves heating the trees in tents (right). MORE ONLINE ngm.com/more INTERVIEW “Unless you have a concept behind the picture, you’re not going to remember it.” —P hotographer CRAIG CUTLER shows the detailed drawings he made before shooting this story.