The Washington-based group is announcing its plans Sunday. Cameron planted the first of 1 million trees in April in Brazil.
In the U.S., trees will be planted in New York, San Francisco and Los Angeles to improve air quality and urban animal habitats.
Tree plantings in such places as Mexico, Canada and Spain will be focused on reforestation of depleted areas.
Other efforts tie in with both development and environmental improvements. In Haiti, the U.S.-based Trees for the Future will work with farmers to plant about 500,000 fruit trees and other native species to provide economic benefits. That makes Haitione of the largest sites.
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