June 7, 2010

Genetically Altered Trees To Help Other Trees

The commercial paper industry's plans to plant forests of genetically altered eucalyptus trees in seven Southern states have worried critics that a large introduction of a bioengineered nonnative plants could throw natural ecosystems out of whack.

ArborGen got U.S. Department of Agriculture approval last month for field trials involving 250,000 trees planted in 29 sites during the next few years.  Much smaller lots of the genetically altered eucalyptus trees have been growing in some of the states for years.

Australian eucalyptus trees grow faster than native hardwoods and they also produce high-quality pulp perfect for paper production.  However, they have been able to only survive in very warm climates. 

Test sites will cover about 300 acres in Florida, South Carolina, Texas, Alabama, Mississippi, Georgia and Louisiana.

ArborGen's experiment marks the first large planting of designer trees in the U.S.  The biotechnology venture company says plantations of hearty, faster-growing eucalyptus could produce more timber in a smaller area and allow conservation of natural forests.

However, critics say that not enough is known about their effect on natural surroundings.

"We have many reservations about it," Neil J. Carman, a biologist who serves on the Sierra Club's genetic engineering committee, told The Associated Press AP). "We don't think the scientific evidence is in yet that says this is a good idea."

Executive director of the activist group Global Justice Ecology Project, Anne Petermann, said eucalyptus trees are invasive, require vast amounts of water that could reduce groundwater levels, and increase the wildfire risk because they are so flammable.

"This is quite a dangerous tree to be mass planting," Petermann told AP.

However, ArborGen CEO Barbara Wells said the trees have not proven invasive in dozens of tropical countries where they are widely grown on plantations.  Also, the company genetically modified the trees to limit their ability to disperse seed and spread.

"The total is 300 acres, but when you're doing tree research, that really is very small acreage," she said, noting that about 20,000 acres of genetically unaltered eucalyptus trees are already grown in central and southern Florida for production of wood chips and mulch. The new test forests will show whether the genetically altered trees can thrive farther north in Florida, where freezing temperatures can occur in the winter.

Donald Rockwood, a professor emeritus in the University of Florida's School of Forest Resources and Conservation, worked for about 30 years on developing eucalyptus trees that thrive in Florida.  He uses traditional breeding techniques, not genetic modification.

Rockwood said the genetically unaltered trees growing in controlled plantations in Florida have not proven invasive, are relatively efficient users of water and are no more flammable than other hardwoods.  Rockwood was hired by ArborGen to do a report on eucalyptus trees' invasiveness because of his experience working with them at the university.

He said introduction of any genetically altered species poses a risk.  For example, the gene that makes the trees resistant to cold could be transferred to surrounding plants, allowing them to spread farther north than nature instead.

"It certainly needs to be done carefully, it needs to be regulated and there needs to be a period of well-defined observations," Rockwood told AP.

The ArborGen trees will be planted in seven counties throughout Florida, four counties in South Carolina and Texas, two in Alabama and Mississippi and a single county in both Georgia and Louisiana.  Rockwood said the trees can grow about 25 feet per year and be ready to harvest in less than three years.


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