In China's far west Xinjiang province, the abundance of sunlight and rich soil boosts its cotton output year after year. But while farmers in Xinjiang never have any problem with the sowing and planting of cotton, they always have a problem with labour shortage during harvest season. The Xinjiang Uighur Autonomous Region is China's largest region, covering one sixth of its national territory. Yet its population amounts to only 1.5 percent of the entire country. To help harvest and supply the cotton for China's ever-growing textile industry, hundreds of thousands migrant workers from other parts of the country flock into the province during the months of September and October. The cotton-picking season, known as the "white gold" rush, becomes source of income for many farmers coming from outside the province. Coming from one of China's poorest regions of Gansu, Zhang Jianxia has been commuting to pick cotton in Xinjiang for the past three years, where the 33-year-old could earn double the amount of money she was making back home. "I have a much better income here in Xinjiang than in Gansu. I only make about 1000RMB (125 U.S. dollars) for two months' farming work in Gansu, but I can make at the very least 2000RMB (250 U.S. dollars) here in Xinjiang," Zhang said. For every kilo of cotton Zang picks, she makes about 10 cents. "Cotton here takes up a big portion of the agricultural production. We also have other agricultural products in this area. But we need a lot of people working on the cotton field especially around this time of year," said Li Weidong, manager of Baotouhu Farm, one of Xinjiang's biggest cotton farms. Baotouhu Farm produces about 7500 tons of cotton each year and employs about 2000 migrant workers during the picking season. Small-scale cotton farms in the area also need the help of migrant workers. "I have nearly 70,000 square meters of land. I hired more than ten migrant workers to help with the harvest. If I relied on my own family members to reap the cotton, it would have been absolutely impossible to do," said Zhang Xiaoling who is in charge of a small cotton field near the Baotouhu Farm. Some 800 million of China's 1.3 billion people live in the countryside. In the past 20 years, some 120 million people have become migrant workers -- earning a living in other parts of China. "If we tried to do everything by ourselves in this big region, we wouldn't have enough people. The whole concept of labour market has been completely changed nowadays. You can never block or seal the floating of labour forces anymore, There are too much to do for the local Xinjiang people," said Wang Lequan, Party Secretary of Xinjiang. China, the world's largest producer and exporter of textile products, is expecting a 10.5 percent rise in its cotton production this year. But despite a good harvest, the domestic supply of cotton still falls far short of demand.