'Only God can make a tree,' the old poem proclaims, but scientists are working to disprove that quaint notion. Timber and paper companies and their researchers are quietly, doggedly working to genetically engineer trees with traits that boost the bottom line: faster growth and stronger insect resistance, for instance. But they know that one of the biggest barriers to their biotech dreams may not be in the lab or the field but in the arena of public opinion.

Internationally, the issue already has triggered opposition. In April, delegates to the United Nations Convention on Biological Diversity in Curitiba, Brazil, passed a formal declaration urging caution on genetically engineered (GE) trees. Environmental advocates warn that engineered traits from GE trees could taint other forests, just as GE crops have contaminated other farm fields.

Industry executives, memories fresh with 'Frankenfoods' protests and agriculture trade barriers, must shudder when they hear such talk. At a 2004 North American timber industry biotech conference with the upbeat title 'New Century, New Trees,' a consistent theme was the need to avoid battles like those over genetically engineered crops. One presenter predicted that 'genetic engineering technology will become a lightning rod for controversy, much like the spotted owl did 15 years ago.' Another emphasized the need to obtain a 'social license' for GE trees.

Such a license may be hard to get, if events in Europe are any indication. In 2004 activists destroyed 400 GE birch trees in Finland, and public opinion pressured paper giant Stora Enso, among other firms, to curtail introduction of the GE trees. The European Union requires that GE trees be proven to present zero social or environmental risks before they're introduced outdoors.

That's a tougher standard than in the U.S., where regulators tolerate 'low-risk' GE tree biotechnology. The Agriculture Department's Animal and Plant Health Inspection Service, or APHIS, must approve any outdoor introduction of GE trees, from initial field trials to full-scale 'deregulation' allowing commercial growing and marketing.

So far, only one tree, a Hawaiian papaya, has cleared all hurdles to achieve deregulated status. But the tree, which was genetically engineered to resist the ringspot virus that decimated Hawaii's papaya industry, hasn't exactly been a success story.

The Environment News Service (Sept. 10, 2004) reports that genes from the virus-resistant tree, introduced in 1998, have spread to organic farms and wild papaya stands. Farmers who grow organic papayas say they've lost access to foreign markets that are tough on GE imports and have incurred higher testing costs, while environmental advocates and backyard growers worry that traditional papayas may be obliterated. To boot, the Honolulu Advertiser (March 19, 2006) reports that genetically engineered fruit commands a lower price, and that Hawaiian papaya production has tumbled anyway since 2002 due to myriad forces.