The shea tree has many uses, both economic and environmental to the people of the Northern and Upper regions, and Ghana as a whole.
The shea tree, was scientifically known in the past as ‘Butryospermum paradoxum’, but is now called ‘Vitellaria paradoxa’. The oldest specimen of the shea tree, according to existing literature was first collected by Mungo Park on May 26, 1797.
Many vernacular names are used for the shea tree, and this shows how widely it is spread across parts of Africa – nearly 5,000km from Senegal to Uganda across the African Continent.
The shea tree grows very well on a wide range of soils, including highly degraded, arid, semi-arid and rocky soil.
It usually grows to an average height of about 15 meters and girths of about 175 meters with profuse branches and a thick waxy and deeply fissured bark that makes it fire resistant. The shea tree grows naturally in the wild in the dry Savannah belt of West Africa from Senegal in the west to Sudan in the east, and onto the foothills of the Ethiopian highlands.
It occurs in 19 countries across the African continent, namely Benin, Ghana, Chad, Burkina Faso, Cameroon, Central African Republic, Ethiopia, Guinea Bissau, Cote D’Ivoire, Mali, Niger, Nigeria, Senegal, Sierra Leone, Sudan, Togo Uganda, Zaire and Guinea. In Ghana (FAO, 1988a), it occurs extensively in the Guinea Savannah and less abundantly in the Sudan Savannah.
The shea tree grows mostly in the wild state. In Ghana, it grows in almost half of the country. It occurs over almost the entire area of Northern Ghana, covering land area of over 77,670 square kilometers in Western Dagomba, Southern Mamprusi, Western Gonja, Lawra, Tumu, Wa and Nanumba with Eastern Gonja having the densest stands. There is sparse shea tree cover found in Brong-Ahafo, Ashanti, and the Eastern and Volta regions in the south of the country.
And according to legend among local people no one owns the shea tree, because it germinates and grows on its own.
The shea tree, when it passes the germination stage in about three to five years becomes fire resistant. It is also not known to have natural enemies such as pests.
Once it survives the first five years of its early stages of germination and growth, it grows slowly and takes about 30 years to reach maturity and from here, it can live for up to three hundred years. In the absence of any hazards, including tree felling, it can bear fruit for two hundred years.
The shea tree has no capacity for vegetative regeneration, and therefore, can only be propagated through its seed.
Economic and cultural importance of the shea tree
The economic importance of the shea tree can not be over emphasized, in the face of the unstable world market price for cocoa and the need to find suitable substitutes for cocoa in the confectionery and cocoa butter industry. This importance became even more significant since the early 1970s.
The shea tree also has a great, untapped capacity for producing copious amounts of sap that can constitute an important source of raw material for the gum and rubber industry.
The mature kernel contains about 61% fat which when extracted is edible, and can serve medicinal as well as industrial purposes.
The trees begin to bear fruits at maturity and start flowering by early November, with picking or gathering lasting for five months from April to August every year. When the shea fruits ripen, they fall under their own weight to the floor and are gathered by hand.
It is estimated that about 9.4 million shea trees are in Ghana, and these can potentially yield one hundred tons of shea nuts worth about 100 million US dollars per year.