Patrick Desir of Poussieres de Vie with Ba Na friends at a festival in Kon Tum
The Ba Na people toiled all day in the fields yet had little to show for their efforts and often went hungry.
The situation troubled and intrigued Patrick Desir, whose charity organization helps six orphanages in Gia Lai - Kon Tum for parentless children of the central highland tribe.
Orphanage staff would travel up to a dozen kilometers to get to the fields where they grew the traditional cassava as the closer land was so degraded it was useless for cultivation.
The yield from their distant crops was typically one fifth of what cassava growers elsewhere were achieving.
"They have land but some of them are very hungry and have no food to eat," said Desir, who co-founded Poussieres de Vie in Ho Chi Minh City 15 years ago, initially to run English and computer classes for poor children.
The problem was soil degradation, so Desir brought in a French agriculture specialist and together they worked out a plan of action.
After a year's preparation, Desir began his soil improvement program early in 2011 to benefit the 700 children in the orphanages as well as some household farmers.
"Because of the worsening soil situation, the nuns at the orphanages have to go farther and farther to find arable land for cultivation. Some of them must travel up to a dozen kilometers every day just to get to the fields," he explained at the time.
"As they have been growing only cassava for many years without change, the soil has become degraded and the crop yield is barely one fifth that achieved elsewhere."
The most important change was to switch from cassava to ground nuts and beans, both of which nourish the soil, and begin cultivating industrial plants such as rubber and bloi trees for their long-term benefit.
To further improve the soil, Poussieres de Vie supplied the growers with different types of fertilizer. It also provided the seeds and seedlings.
"We chose new crop varieties after analyzing the soil models. The situation won't change overnight but the idea is sound," said Desir.
"Now they're mixing long-term trees such as bloi and rubber with short-term nuts and beans so they can have some money for their daily living expenses while they wait for the industrial trees to start producing.
"The first harvest of the new program will be in December or January. Already at this stage the results are encouraging."
Poussieres de Vie has even lent money to one of its local employees to take care of her own farm while fixing the land.
"She keeps a detailed diary of our land-improvement efforts so that we can have a permanent record for the benefit of others," said Desir.
"My hope is that, thanks to the land-improvement program, their incomes will be higher and their children will have a better and more balanced diet.
"It means that the sisters at the orphanages can spend more time taking care of the children instead of toiling away on the farm for little result."
At the beginning, the nuns couldn't understand why he was doing so much for the Ba Na people.
In fact, Patrick Desir has done a lot more in the years that he's been traveling to Gia Lai - Kon Tum.
One of these is his home-stay project where Ba Na families accommodate overnight tourists to boost their income.
Desir has also built a Ba Na-style guest house in Kon Tum, and arranged a home-nursing service for which he brought out a French nurse to train the local nurses.
Preserving Ba Na culture is important to him as well, and to this end he has established a library and encouraged the Ba Na people to write down their tribal stories and history.
"Theirs is an oral tradition. That's how everything is passed down from generation to generation, and that's why the Ba Na people are at risk of losing their culture. Getting it all down on paper is vital", Desir said.
It's easy to see why the Ba Na revere this man of Vietnamese, Chinese and Indian descent who moved from Vietnam to Paris with his family when he was 15 years old and returned in 1997 to start a software company exporting its wares to France.
As time passes and his involvement deepens, Patrick Desir is growing ever closer to the Ba Na people.
"Some even say that I look like a Ba Na man," he said with a warm smile.