. >> this week in global i ideas,e asascend to the lofty heights f the andes, where deforestation of high-elevation woodland is a huge p problem. our reporterer claudia laszczk met villagers in peru who are planting tens of thousands of new trees in an effort to combat climate change. >> quena raymi is a very special festival held once a yeaear in e peruvian andes. it's a tree-planting ceremony attended by over 200 men, women , and children from various villages in the area. once the festivities are over, they begin their hike up the mountain, carrying shovels and other tools, and provisions with them. plus infants and the saplings -- even the llamas come along. their two-hour trek takes them to an altitude of over 4000 meters above sea-level. they follow anicent paths once used by their ancestors. the incas lived in harmony with their environment. for today's population, the idea is to give back what they have taken from nature. the past few centuries have seen the area almlmost completely deforested, with no effort to replenish the devastated woodlands. these people are the first g