The planting of exotic trees is more harmful to the biodiversity of Argentina's Patagonia region than the presence of livestock or even the damage caused by forest fires, warns Estela Raffaele, of the National Council for Scientific and Technical Research. Raffaele pointed to the rise in the area planted with pines outside the city of San Martín de los Andes, near the Chilean border, replacing the 'aracucaria,' a tree native to this mountainous area.

The shade of the non-native trees prevents the growth of bushes and the pine needles collect on the ground in a layer that prevents the germination of seeds from other plants.

The case of pines in Patagonia will be debated by logging business leaders, lawmakers and researchers from Argentina and Chile at the first Bi-National Conference on Ecology, to take place later this month.