Eucalyptus trees deadly for Africa – Nobel Laureate

By: Emmanuel Okella on August 27th, 2009

Eucalyptus has become one of the most planted tree species in Africa in recent years.

Globally, more than 80 countries have planted more than 4 million hectares of eucalyptus, according to Dr. Richard Matsekele of the Zimbabwe Environmental Research Institute.

The tree grows much faster than many other species, produces sizeable timber, poles for supporting electricity and telephone lines as well as scaffolding, and is rarely affected by dry spells.

It has also been credited at times for draining mosquito infested swamps, thereby reducing the risk of malaria.

But all these benefits are not worth it, according to according to Nobel Laureate Wangari Maathai, also the founder of the Green Belt Movement, who said these alien trees are “over-promoted for commercial reasons”.

Prof. Maathai told journalists on the sidelines of the second World Congress of Agroforestry in Nairobi that eucalyptus represented a dark chapter on Africa’s environment systems.

In a keynote address at the congress she expressed concern that in many parts of East Africa indigenous trees have been depleted and replaced with foreign species, including eucalyptus.

She said mitigating the effects of climate change would be even harder for the region because eucalyptus trees continue to be planted along rivers and in wetlands and watersheds.

“As long as we continue planting these trees in watershed areas and in our forests, we will continue to experience water shortage and it will even become a bigger problem as climate change hits us,” said Maathai, who won the Nobel Prize for her tree planting campaign.

She added: “These trees are good for the beauty that they offer but consume a lot of water when planted along rivers and around wetlands and watersheds.”

Maathai said apart from the negative impact on water systems, the eucalyptus, which is called the water drinker or guzzler in her native Kikuyu, is also hostile to other species and almost the entire local biodiversity.

“When you go into these monoculture plantations, they look like dead forests because it’s only them,” she said. “You don’t see birds, butterflies, other trees, animals—anything other than them because they don’t allow any other growth.”

In Maathai’s country, Kenya, eucalyptus planting is already being restricted. The country’s Environment minister, John Michuki, three months ago ordered the uprooting of eucalyptus trees from wetlands and banned their planting along rivers and watershed. He said the species was a threat to the environment especially in water catchment areas.

Similar controls have been instituted in a number of countries including Australia, Brazil, and South Africa where some of the alien tree’s species have been banned.

But a recent report by the Food and Agricultural Organization (FAO) said that despite the controversy, because of its fast growing nature, eucalyptus could remain a viable alternative, especially in developing countries where population growth is matched with the demand for wood for fuel, shelter and other needs.

The FAO forestry paper estimated that in the tropics, only one hectare is planted for every 10 hectares of natural forests cleared. The report notes that to cope with this situation, the choice is to plant fast growing, adaptable and exotic species like eucalyptus that have a multiplicity of uses.

Some environmental scientists who have defended eucalyptus argue that the tree has over 700 species that are adaptable in different environments worldwide, emphasizing that each species should be assessed separately.

But Maathai maintained that Africa’s future lies in planting indigenous species and warned that the continent would pay with lives if the current trend was not reversed.

“God had a reason to put some species somewhere so that we have appropriate habitats for particular parts of the world,” she said, “so when you bring eucalyptus from Australia, you are killing yourself.”