Global Project Aims to Plant 5.5 Billion Trees on Poor Farms

By John Roach
for National Geographic News

August 23, 2001
Money doesn't grow on trees. But growing trees on farms can enrich the
lives of the world's rural poor, says an international research center
that aims to help farmers in developing countries plant 5.5 billion
trees by the end of this decade.

The tree-planting campaign, if successful, will create the equivalent of another major tropical forest while improving the livelihood of as many as 80 million people, according to the International Center for Research in Agroforestry (ICRAF), which is spearheading the project.

Scientists at ICRAF and other organizations study ways of encouraging poor farmers around the world to incorporate trees into their land holdings—a practice known as agroforestry—because of the many benefits trees can provide.

Agroforestry "is not trying to convert agricultural land to forestry land," said Greg Ruark, director of the National Agroforestry Center in Lincoln, Nebraska. "Instead, what it tries to do is integrate trees and shrubs into ongoing agricultural operations, trying to get at conservation benefits and economic diversification for the land owner."

Planting trees on farms reduces erosion, improves plant nutrition for food crops, and replenishes the fertility of poor soil, says ICRAF. Trees also provide critical shade in the tropics and help regulate the microclimate of farms.

"These benefits in themselves improve the welfare of farmers and improve the production of crops," said Anne-Marie Izac, director of research for ICRAF, which is based in Nairobi, Kenya.

But in addition, trees and shrubs are a major source of products for trade and household use, she explained. They provide edible fruits, firewood, timber poles needed to build houses and other buildings, and in some cases bark or other products of high commercial value.

On a much bigger scale, trees provide habitat for a wider range of biological diversity, and they mitigate global warming by sequestering carbon.

ICRAF sees agroforestry as a strategy for simultaneously reducing poverty in the tropics and taking carbon out of the atmosphere and putting it back into soil and vegetation.

Planting 5.5 billion trees would increase the incomes and assets of people in the developing world by U.S. $3 billion and remove more than 100 tons of carbon from the air, according to ICRAF's estimates.

Ancient Practice

Agroforestry is hardly new. Farmers have grown trees on their farms and pasture lands for millions of years. About 25 years ago, researchers at the International Institute for Tropical Agriculture in Kano, Nigeria, coined the word "agroforestry" in reference to that ancient practice.

ICRAF works with many local organizations to make agroforestry viable and economically beneficial to poor families in tropical regions. Researchers have studied agroforestry in a number of countries to find out what methods work best. In Indonesia, for example, trees have been an integral part of farms for centuries.

By combining traditional farming practices with elements of modern ecology and social science, ICRAF develops agroforestry approaches suitable for a variety of local conditions.

Acquiring a better understanding of how trees interact with soil and crops, for example, helps scientists develop agroforestry methods that minimize competition between various plant species. That kind of knowledge is especially useful in places such as Africa, where the soil is often poor and its nutrients minimal.

At the same time, social scientists look at socio-economic factors that are likely to affect whether poor farmers adopt agroforestry practices. These considerations are incorporated into model agroforestry systems to provide incentives and ensure broader acceptance.

"Our understanding of the scientific basis of agroforestry and its potentials has increased substantially during the past two decades," said P.K. Nair, director of the Center for Subtropical Agroforestry at the University of Florida in Gainesville and editor-in-chief of the journal Agroforestry Systems.

Seeing Results

The potential benefits of agroforestry are evident in the re-greening of the Shinyanga region of Tanzania, which has been deforested and overgrazed.

Most of the trees in the region were cut down in the 1970s in an effort to halt infestation by tsetse flies, which carry a parasite that spreads the sleeping disorder trypanosomiasis to people and livestock. In the decades that followed, the remaining trees were cleared for cattle grazing and cotton plantations.

In 1986 ICRAF established a partnership with a local development agency, Hifadhi Ardhi Shinyanga (HASHI), to promote agroforestry in the area. The government later joined the efforts.

Farmers in the region became enthusiastic about agroforestry. Local people now grow trees that provide much-needed wood for fuel and construction. The trees have curbed soil erosion and helped preserve precious watersheds.

Today the project is considered a success in part because agroforestry practices were widely adopted without coercion.

At their own initiative, Anthony Paulo and his wife, Agnes Saidi Shabane, planted 100 trees on their farm in 1997 to provide fuelwood.

After their neighbors told them about the ICRAF-HASHI project, the couple joined the local efforts. They have trained more than 1,000 farmers in 14 villages in how to implement agroforestry techniques.

ICRAF does not pay the couple, but gives them starter seeds and the knowledge they share with others. They were also given bicycles on which to travel from village to village.

Through similar partnerships and "multiplier" efforts in many other countries, ICRAF is working to expand agroforestry in other parts of Africa and in South Asia, China, and Latin America.

If this networking effort is successful, farmers in tropical countries could help ICRAF meet its goal of planting 5.5 billion trees—a figure that Izac said is a rough "back of the envelope" calculation.

Although the campaign is ambitious, Nair said it's highly promising. "If the right types of trees could be planted in the right manner at the right places at the right times," he said, "and if the trees are taken care of properly—if the enthusiasm does not stop with planting, as is usually the case—it will certainly be a good thing."

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