By Mark Kinver
Science and environment reporter, BBC News
"In the absence of trees, our communities would simply collapse," states Andrew Dokurugu, a project officer for Tree Aid.
Speaking from the charity's West Africa offices in Burkina Faso, he explains how trees are vital for poor rural villages to survive in the long-term.
"We are looking at ways to promote sustainable agriculture and agroforestry," he tells BBC News.
Fruits, leaves, wood and bark provide the vital resources for rural life
"This will help ensure that the remaining trees are well looked after and that communities have access to the trees they require."
Using the Family Trees and Land Use scheme in northern Ghana, one of Tree Aid-led projects that have helped 600,000 villagers, Mr Dokurgu outlines why so many communities in West Africa are facing tough times.
"Rural settlements located close to big cities have particularly difficult challenges," he says.
"Urban developments damage the environment and remove trees for use in the cities.
"This quickly deprives rural areas of their sources of food, fuel and other tree products."
Rising urban populations and expanding cities makes life tougher both inside and outside the city boundaries.
Seeds of growth
Tree Aid was set up in 1987 by a small group of foresters who were keen to use their expertise to help people in Africa, explained programme director Tony Hill.
Growing demands means natural regeneration is no longer enough
"They saw that trees, potentially, were a way for poor rural families to help themselves in the long-term," he told BBC News.
And in 1997, the charity established a permanent office in Ouagadougou, the capital of Burkina Faso.
Mr Hill described this development as a "step change" for Tree Aid, which has now planted more than 6.5 million trees.
"We were then able to work directly with local partners," he said.
"Projects always have a beginning and an end, but the needs of the villagers do not end when the scheme finishes - particularly when you are dealing with trees.
"You need to have the continuity of attention, care and protection if you are going to deliver the benefits long-term."
Planting trees offers a better outlook for future generations
The need to plant and manage the region's tree stocks is becoming increasingly important, Mr Hill says.
"If you go back several decades, the wild tree resources were rich enough for villagers to get more or less all of the products they needed without having to plant trees.
"Now, growing populations and an erratic climate means that villages have to invest in trees, rather than letting nature do its own thing."
However, it is not simply the case of telling people to plant saplings and sitting back and waiting for them to grow.
Some cultures, Mr Hill reveals, have traditionally considered planting fruit trees as taboo: "People believed that if you planted a tree, you were bound to die before it bore fruit."
But he says one of the biggest challenges is the issue of land tenure.
"For farmers, it is like a declaration of ownership. Planting trees says 'this is my land and it is going to be mine for a long time'.
Tree produce is the sole source of income for many people
"For many people, it is difficult to negotiate adequate secure tenure and get permission from all of the relevant authorities."
This is one area where Tree Aid has been focusing its efforts, especially for women, who generally are not allowed to own land.
"In the drylands of Africa, where Tree Aid operates, the real value of trees is the products that they can take: fruits, leaves, bark and roots, firewood, building materials," Mr Hill says.
He adds that healthy trees also help maintain the area's ecosystems.
"People rely on trees to recycle nutrients, prevent erosion and maintain moderate water flows.
"Without trees in the landscape, you cannot have a sustainable farming system.
"Without farming, you do not have any life in these communities."