UPDATE 2-Florida lost 1 pct of orange trees over year

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By Jane Sutton

MIAMI, Sept 18 (Reuters) - Florida has about 1 percent fewer commercial orange trees than it did a year ago, the U.S. Department of Agriculture said on Friday in a tree census that reflected the impact of tree-killing citrus greening disease.

Both the number of orange trees and the total acreage devoted to citrus groves continued to shrink, though much more slowly than in the past two years.

Florida has 64.99 million commercial orange trees, down from 65.76 million last year, the USDA said. The number reflects an increase in new plantings, which a spokesman for the state's largest growers' association called a positive development.

"The fact they there are replanting shows there is some optimism out there among the growers and that's a good thing," said Florida Citrus Mutual spokesman Andrew Meadows.

Commercial orange trees generally produce fruit after about three years of growth, and 93 percent of Florida's trees were bearing, unchanged from last year, the USDA said.

The agency will issue its first crop size forecast in October for the 2009-2010 harvest, which runs from September through June.

Florida is the world's second-largest citrus grower and produces three-quarters of U.S. oranges, most of which are processed for juice.

Florida has lost more than a fifth of its orange trees and its citrus acreage in the last five years due to disease, hurricanes and urbanization. The latter is no longer a factor, with the collapse of the real estate market, and Florida groves have been spared from hurricane damage this year.

But citrus greening, an insect-borne bacterial disease that kills trees, has spread widely since it first appeared in 2005. Florida is still battling a long-running outbreak of citrus canker, a bacterial disease that can make the fruit drop before it is ripe.

Commercial citrus acreage in Florida shrank to 568,814 acres, down 1.3 percent or 7,763 acres from last year, due in part to removal of trees infected with citrus greening or citrus canker.

Of that, 492,529 acres were planted with orange trees, the lowest number since 1986, when major freezes ravaged Florida groves. But the loss was considerably less than in the past two years, said the report from the USDA's National Agricultural Statistics Service office in Florida. (Editing by Christian Wiessner)