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By Marcy Nicholson
SAN CARLOS, Colombia, Oct 19 (Reuters) - Farmers who fled war in the Colombian Andes are returning to revive their abandoned land, cultivating coffee trees that are boosting global supplies of the highest-quality beans.
Colombia's five-decade civil war, the longest in the Americas, displaced millions and disrupted farming for decades in areas that produce coffee for the most exacting consumer.
The revival of coffee farming in the former conflict zones could help boost Colombia's coffee output by 40 percent, according to government estimates. That would raise global supplies of mild arabica beans by about 13 percent.
The additional supply could reduce the cost of the raw material for the world's top roasters, many of whom are seeking to secure increased supply from Colombia.
About 950 coffee-growing families have returned to the San Carlos area, representing about 60 percent of the 1,600 families who left during the war, according to data from the Colombian Coffee Growers Federation (FNC). The supply from this region, about 330 kilometers (205 miles) north west of the Colombian capital of Bogota, could expand further as farmers plant more of their land and more people return to the region to provide the needed labor.
The area now has about 800 hectares of coffee farms, double the low of 400 hectares during the war. That's still only about half of the 1,500 hectares prior to the conflict, according to FNC data.
Among those who returned was Libardo Garcia, who lost two brothers in the conflict - one was shot and the other killed by a landmine. He and his family moved back to their 12-hectare (30 acres) farm in 2015 after fleeing in 2001.
"All the coffee trees were dead when we came back," said Garcia, who has since planted 8,000 trees on two hectares of steeply sloped land.
Arabica is the highest quality coffee bean, and Colombia is the world's top producer of mild arabica. To make that variety, beans are separated from the cherry then dried to increase quality.
Arabica makes up about 60 percent of global coffee supplies, with lower-quality robusta beans accounting for the rest. While some coffee roasters add robusta to their highly secretive blends, premium brands are typically 100 percent mild arabica.
A peace deal between the government and the rebel Revolutionary Armed Forces of Colombia (FARC) in late 2016 paved the way for many to return to their homes and farms, including thousands of coffee growers.
About 220,000 people died and millions were displaced in decades of fighting among leftist guerillas, paramilitary groups, criminal organizations and government forces. The conflict impacted large areas of the country, and the government struggled to exert control over highlands and remote jungle areas in the west and south of the country.
Some farmers who stayed through the violence have also switched to coffee from growing coca and other illegal crops that they cultivated during the conflict. Coca is used for cocaine production, and the cash from growing it helped finance armed groups during the war.
The combination of farmers returning to their abandoned land and others switching to coffee could help boost the country's total output to a record 20 million 60-kg bags by 2020, the government estimates, up from 14.2 million bags in 2016.
In the Andean region of San Carlos, the revival in coffee production has advanced quickly since conflict in the region abated around 2014, when the peace deal was still being negotiated. The country's conflict with rebels began in 1964 and peaked in this region around 2000.
After fleeing his farm, Garcia spent time in the city of Medellin and then in the town of San Carlos.
"We came back because we love the land," he said, leaning against the fence outside his home, a brick house adorned with baskets of flowers.
Wearing a wide-brimmed hat, Garcia pointed out a former FARC stronghold in the distance, in tree-covered mountains about an hour's walk from his farm.
Most of his neighbors have yet to return, he said, either because they are skeptical the peace will last or because they have made lives elsewhere.
Before moving his family back, Garcia traveled the 13 kilometers from nearby San Carlos every weekend for three years to plant new coffee trees and remove the dead ones.
Garcia has plenty of land to expand his farm further but cannot yet find the labor because too few people have returned to surrounding communities.
New high-yielding trees have helped boost harvests, but the region is still far from reaching its potential because of the labor shortage, said Rosa Velasques, manager of the local cooperative where about 1,000 local farmers sell their beans.
International roasters have jumped at the opportunity to buy more beans from Colombia, the world's third-largest coffee producer and the source of a third of the world's mild arabica supplies.
Italian roaster illycaffe has expanded its buying to parts of the country that were unreachable during the violence.
"Now they've opened up," said illycaffe Chairman Andrea Illy.
The firm had increased purchases from the region by double digit percentages for the last two to three years, Illy said, and it expects growth to continue at similar rates.
In 2016, Nestle Nespresso bought its first coffee from a post-conflict region of Colombia and launched it this year as a limited edition.
"A lot of these regions, nobody had even been in and tasted the coffee until recently," said Katherine Graham, Nestle Nespresso's corporate communications manager.
"There are some areas with strong potential," Graham said. "But it needs a lot of development, a lot of work."
Starbucks Co expanded its partnership with the United States Agency for International Development to give 1,000 farmers in post-conflict zones agricultural training. It also partnered with the Inter-American Development Bank to support 2,000 farmers in Colombia - mainly women - with a loan initiative.
Colombian entrepreneur Gonzalo Navarro launched a roasting company called Piccolo Piacere in Medellin earlier this year, focusing on sourcing from small coffee growers, many in former conflict zones.
"We have access to farmers who in the past were growing other things, such as coca," he said.
Back near San Carlos, farmer Rubiela Cuervo works a remote farm with her family. She fled to Medellin to escape the violence in 2005 but struggled to make a living and returned a year later despite the ongoing violence.
She has expanded the farm as peace returned to the area in recent years.
"We hope that peace will bring us more employment, more income for our work," she said. "I'm hoping not to be displaced again."
Editing by Simon Webb and Brian Thevenot