BEIJING May 15 (Xinhuanet)--China embarked Tuesday on a 20-billion-yuan (US$2.4 billion), 10-year program to plant 170,000 square miles of trees - an area roughly the size of California, China Daily reported.

   It is the largest reforestation project ever, forestry officials said, suggesting only an unprecedented effort can stop the expanding deserts, chronic droughts and deadly flooding blamed on wholesale logging.

   Lei Jiafu, deputy administrator of the State Administration of Forestry, acknowledged that a smaller - but still substantial - tree-planting program under way since the 1980s was not enough to stop the degradation of China's forests.

   "China has not fundamentally reversed the trend of a deteriorating ecosystem," Lei said at a news conference to announce the plans.

   Throughout much of the last century, China, the world's most populous country, thought little of cutting down its forests. With 1.3 billion mouths to feed and a burgeoning economy, it needed both the land and the timber.

   The numbers reveal the damage. Now only a few percent of the country's original forests still stand, despite the millions of trees planted since the 1980s in the smaller-scale effort.

   The plans unveiled Tuesday embrace six separate projects that range from reforesting hillsides to creating protected grasslands and nature reserves for pandas, Tibetan antelopes and rare orchids.

   One problem facing the new, bigger effort will be finding the trees. China has a thriving tree-farming industry but whether it can produce all the seedlings required remains to be seen, Lei said.

   In the 1950s hills were stripped of trees to fuel steel furnaces and to clear farmland. That has left hillsides unable to trap rainfall, worsening summer floods that often kill hundreds of people along the Yangtze River in central China, and in the northeast.

   In the '90s, efforts to expand grain output led to the clearing of more hillsides and farming in areas with fragile soil that quickly gave out and turned to wasteland. That has led to the spread of deserts in the north and sandstorms that scour Beijing and other major cities

   Officials plan to create barriers to shield Beijing and other cities from sandstorms by planting trees on 10,500 square miles of farmland, Lei said.

   Beijing already has planted such barriers on a smaller scale, cutting the size of gritty dust storms that smother the Chinese capital each spring.

   China banned logging in 1998 in large areas of the vast western province of Sichuan, where forests had been turned into fields of stumps. Experiments began that year with planting trees on farmland.

   To replace logging in forests, China plans to start commercial tree farms this year, financed by private investors, Lei said.

   Plans call for 82 million acres of tree plantations to be created over the next 10-15 years, Lei said. He said officials also hope to reduce demand for timber by boosting efficiency in China's lumber and paper industries.

   Lei said the nationwide effort still faces serious obstacles, including a shortage of money and uncertainty about the best species of trees to plant in many areas.

   Nevertheless, he said, "We believe that we can achieve our goals in these programs." Enditem