By the BBC's Joan Baxter Segou, central Mali

For centuries, even millennia, farmers in the dry Sahel, south of the Sahara desert, have farmed with trees, which provide them with many of their needs and nourish the soil at the same time.

Farming fields in Mali are dotted with trees that farmers have always protected and used for food, medicine and other valuable products - trees so important to their survival that in some cases, they are worshipped.

It is a symbol of woman and without a woman there is no life

Hasshim Sow Scholar and elder

March is the peak of the dry season in Mali. And on the outskirts of Segou, the country's second largest city, the fields are brown, awaiting rains.

However, farmers during this season harvest important crops that grow not on the ground, but on the only green trees that dot the dry fields of this harsh Sahelian landscape.

These tall majestic tree are known here as Balanzan.

Enriches the soil

Gajuma Coulibaly was lopping branches off one of the trees when I visited his farm.

Balanzan leaves are food for livestock during the dry season

He told me that Balanzan is a very special tree in Mali and nowhere more so than in the region of Segou, which is known as the City of Balanzan.

Mr Coulibaly said that the Balanzan tree is a big part of his farm.

It enriches the soil in his farmland giving good millet yields.

He also harvests the Balanzan leaves to feed his cows and sheep.

A Malian researcher working in Segou, Bocary Khaya, knows all about the value of Balanzan, known to scientists as Faiderherbia albida.

Firewood

"In the Sahel, where fodder is not always available, this tree is special because it sheds its leaves during the rainy season and bears leaves during the dry season", he said.

Mr Khaya explained that people have learned that the crops grown beneath the tree always yield better than the one far from the tree.

"So it is really a fertilizer tree," he said.

However, the Balanzan is on the verge of disappearing because people cut down the big trees to use as firewood.

According to Mr Khaya, very few trees are now left standing on Segou fields, compared to about 50 to 60 trees per hectare a few years ago.

Ancient tradition

Researchers say it is difficult to convince the government, and all those involved in agricultural development in Mali, that ancient farming traditions that involve trees are key to human welfare and even survival.

Hasshim Sow, Bambara elder and philosopher

But for local people it is common knowledge that trees such as Balanzan are not only essential, they are very much a part of the local Bambara culture.

A scholar and Bambara elder in Segou, Hasshim Sow said there could be no life without the Balanzan trees.

"It is a symbol of woman and without a woman there is no life. The Balanzan does not die because it is a symbol of our eternity", he said.