Many countries are wasting millions of dollars planting trees because of myths that forests always help improve water flows and offset erosion, a British-led study says.
Many trees, especially fast-growing species like pines and eucalyptus favoured by the paper industry, suck more water from the ground than other crops, it said. The water transpires from the leaves and so the trees dry out the land. ?Trees on the whole are not a good thing in dry areas if you want to manage water resources,? said John Palmer, manager of the tropical Forestry Research Programme run by the British Department for International Development.
Planting trees may create deserts (New Scientist)
In South Africa, the spread of foreign pine and eucalyptus trees across the country has cut river flow by an estimated 3%. The country is currently employing some 40,000 people to uproot many foreign trees. And it taxes plantation owners for their hydrological damage.
