TREES play an important part in the lives of all Zimbabweans.
They provide fruits, firewood, shelter for different birds and animals and above all, they are believed to be shelters of great ancestral spirits.
When explorer and missionary David Livingstone is said to have ‘discovered’ the Victoria Falls for the British Empire he did not resist the temptation to notice how this country was endowed with big trees and carved his name in 1855 onto a Baobab tree near the waterfalls.
The Big Tree – is one of the best known trees in the World.
The Big Tree is a huge baobab in Zimbabwe close to the Mosi-oa-Tunya or Victoria Falls.
It has sometimes been erroneously called Livingstone’s tree.
Unusual for a Baobab, it has both an impressive girth and is very tall, about 22 metres in circumference and about 24 metres tall.
The Big Tree is about two kilometres from the Zambezi River, the falls and the island where Livingstone arrived in a dugout canoe.
Apart from being the best known, this impressive tree is possibly the oldest and biggest known Baobab tree in Zimbabwe.
Some equally or more impressive trees were lost under the flooding further downstream that occurred after the construction of the Kariba Dam in 1956.
Unlike the animals rescued and saved by ‘Operation Noah’ during the flooding the trees had to stay where they were, many were bulldozed so they would not become underwater hazards.
The Big Tree may be about 2 000 years old using estimates from its circumference and growth ring data collected from other trees under Rhodesian rule.
However, it is deeply incised and there is speculation it may be considerably younger.
The Big Tree is protected by Museums and National Monuments of Zimbabwe under whose jurisdiction it falls.
Over the years, name-carvers have left their mark on the tree, but the tree is now protected from these acts of vandalism by a fence.
However, the future of the country’s most grotesque tree, hangs in the balance as disease and humans are threatening the survival of this respected and biggest tree and others of its kind in Southern Africa.
The BaTonga elders believe the ‘curse’ started when David Livingstone carved his name on the giant tree in 1855 and the ‘curse’ is spreading to other baobabs in the form of the disease.
They believe great ancestral spirits of the Zambezi River dwelt on the tree and when Livingstone etched his name on it, they became very angry and were never appeased therefore causing the sooty disease now threatening the survival of other baobabs in Zimbabwe.
Communities that directly benefit from the grotesque trees in Binga and Hwange are already counting the cost, as they can no longer benefit from the bark, which they traditionally used for making mats and other pieces of craft.
While the robustness and extreme longevity of these trees imply that they are generally healthy, research carried out recently by the Forestry Commission and Environment Africa’s Tree Africa has revealed that the trees are under threat from the sooty baobab disease.
A similar study was done in the late 1980s and established that the disease was a threat to the tree.
It appears the problem is continuing.
Sooty is a fungal disease that attacks the tree in the form of what looks like growths on the bark that eventually get colonised by fungi.
This blackens and thins the bark, resulting in less supply of water to the branches.
A wilted or shrunken appearance of baobabs, with unusually rough, wrinkled and dull rather than smooth and shining bark, is associated with sootiness; fallen, blackened twigs frequently litter the ground below, severely affecting trees.
Over the past 20 years, large numbers of baobab trees in Zimbabwe have been reported to be dying.
The affected trees exhibit a strikingly blackened or burnt appearance.
The condition has been referred to locally and abroad as a new disease.
Investigations by plant pathologists suggest that although the blackening is caused by growth of a sooty fungus, it is purely a secondary manifestation of a physiological disorder.
The tree, whose botanical name is Adansonia digitata, falls in the Bombacacueae family and has a thick fibrous trunk, which grows up to as much as 25 metres in diameter.
In Zimbabwe the tree is commonly found in agro-ecological regions three, four and five in the Zambezi and Limpopo belts.
A recent research document produced by the Forestry Commission and Environment Africa noted that archival evidence shows that exactly the same problem has occurred before and certain trees afflicted earlier this century have since recovered.
It attributed the phenomenon to below average rainfall patterns and the increasingly intensive land use in some communal lands.
According to the Forestry Commission, the sooty disease is associated with drought and the lack of biodiversity as contributory factors.
Overgrazing in the vicinity of the baobabs exacerbated the water deficit.
At the moment, all research that has been carried out point to drought as the major cause of the sooty disease.
Previous researchers, as early as 1951, pointed out that there has been alarming loss of baobabs that had died or collapsed through the 1940s.
The baobabs were also among the most severely affected trees during the worst drought of 1991/1992.
Zimbabwe’s rainfall over the past decade amounted to the lowest cumulative total since records started.
In some communal lands in Binga and Hwange where human population densities are high, while much of the woody vegetation has been removed and the land overused resulting in less herbaceous groundcover, the baobabs have been unable to flourish.
There are clear signs that the communities that benefit from the tree have been affected, as it is used multi purposely as a medicine and source of food by the rural communities in northern and southern parts of Zimbabwe.
The baobab tree is an important food and medicinal source.
The leaves can be used as relish in the dry and arid parts of the Zambezi Valley such as Binga.
When dissolved in water or milk, the pods of the tree makes a refreshing drink, as it can also be used as a substitute for cream of tartar in baking and also as a fermenting agent in traditional brews.
Medicinally, the pulp is consumed to treat fever, diarrhoea and malaria.
However, baobab trees in the area are slowly dying.
Could it be the hand of David Livingstone or merely an act of Mother Nature?