Seeds of Change

With genetically engineered \ntrees already in the environment, \nwho is keeping an eye on their progress?



There are trees along Lolo Creek that were growing strong when Lewis and Clark made their way towards Idaho. You can still picnic under the same Ponderosas that already smelled sweet in 1805. These massive trees have spread across much of the western half of the continent, producing abundant amounts of cones and endless supplies of pollen.

Ponderosa cones are appropriately large, and unless the tree is on a slope, the tree’s “egg” will come to rest near the trunk. The pollen, however, is unloaded into the air, scattered through the valley on summer winds and blown across the valley to drift across the Sapphires and beyond.

Doing their part in this age-old process, these trees once received their genetic code in this same way—a fertile, seed-laden cone was pollinated by another, fell to the ground and sprouted. Tens of millions of years of evolution have produced a family of organisms so successful that trees blanket nearly every corner of the planet.
The most poplar tree around

To survive floods and droughts, cold and heat, plagues and hailstorms, trees have evolved effective strategies, and their genomes are appropriately impressive. Although not yet fully mapped, some conifers may contain genomes more elaborate than our own. Because of this vast microscopic complexity, genetic tree research has been conducted primarily on one of the tree world’s simplest constituents: the poplar.

The poplar is ground zero for arboreal genetic manipulation. DNA is removed from donors ranging from chickens to humans in an effort to breed into a genetically engineered (GE) tree a wide range of characteristics. For example, certain poplars that were genetically engineered to absorb high levels of mercury were planted at the site of a chemical spill in Oregon to leech toxins out of the soil through their roots. The results of this experiment are not yet in, but “phytoremediation” has become a highly touted function in pro-GE circles as they stump for practical applications in their field.

Proponents of this emerging technology see impressive and unlimited potential. Scientists are designing trees that can be processed into pulp with fewer toxins, as well as those that create the bacterial pesticide Bacillus thuringiensis, or Bt, in their cells. They are also attempting to make trees grow faster to allow for more harvests, and make the process of turning trees into pulp less labor intensive and thus more economical. GE advocates argue that turning native forests into cloned tree plantations will allow the nation to meet its ever-growing paper demands and at the same time prevent the cutting of our last remaining old growth forests.

Such efforts come at a critical time, as Americans’ annual paper consumption has reached a level three times the global average—enough to fill two million train cars that would circle the planet—and it is still growing. By 2010 our seemingly insatiable demand for wood-based products will exceed production, leaving the timber industry scrambling for biotech solutions to increase the productivity of their lands.

Meanwhile, conservationists are eyeing ways to reduce demand and are looking towards alternative cellulose in plants such as hemp or kenaf. This year the Montana Legislature recognized hemp’s value as a tried-and-true fiber, passing legislation to allow Montana’s farmers to grow the traditional plant—assuming the federal government repeals the nationwide ban on hemp.

American demand for paper products has resulted in the clear-cutting of nearly all of our nation’s accessible large trees, and the industry’s pipeline of federally-subsidized cellulose fiber is running at historically low levels. With all but a few sizable trees off limits to chainsaws, the Northwest’s timber industry is looking for new ways to be profitable, leading Big Timber to enter into mergers with biotech and chemical firms.

These may well prove to be mutually beneficial relationships: Timber companies provide the land, biotech firms provide the GE tree stock, and the chemical industry creates the herbicide and insecticide applications. Creating more productive and faster growing trees, proponents say, could relieve pressures to log native forests.
Sterile vs. virile

Researchers are also attempting to create trees that are unable to reproduce. If a GE tree matures at a test plot in Washington, its pollen can be blown on the jet stream for hundreds of miles across Washington, Idaho, and Montana. (Currently, there are no federally-registered GE tree test sites in Montana.) Tens of millions of years were required to create the arboreal diversity that functions so successfully on our planet, significantly longer than the few decades that human genetic knowledge has allowed for DNA-level reconstruction.

The science of genetically engineering trees is very young—if it were a human, it would not yet be able to drink a beer—and critics aren’t convinced the technology is safe. The majority of GE research has been agriculture-based, not ecosystem-based, and the effects on surrounding populations of similar species have not been adequately studied. Most GE crops, like corn, soy and canola, live for a single growing season before they are harvested, allowing the plant’s entire life cycle to be studied. Trees, however, with their more complex genomes, may contain dormant strategies to override introduced traits. Extensive, long-term studies have yet to be conducted to determine with any certainty that the technology can be trusted, and critics warn that test sites should be closely monitored to prevent unintentional cross-pollination.

Like native trees, non-sterilized GE trees will spread their pollen vigorously, potentially creating widespread and unaccountable genetic “pollution” as their DNA wafts through our planet’s forests. GE critics fear that trees that create their own insecticide, for instance, may create toxic soils as well, after their leaves or needles shed and decompose on the ground.

Trees genetically altered to contain less of their woody lignin are more easily converted to pulp, but a low-lignin gene released into a forest may also cause trees to be insufficiently rigid and prone to blow over. Likewise, a GE tree producing the Bt insecticide could potentially spawn GE supertrees, another name for non-native, tree-like weeds.

“Genetic drift and contamination is a great concern,” says Native Forest Network GE tree specialist Brad Hash. “Given this drift and the fact that no researcher has ever guaranteed 100 percent sterility, there’s a significant contamination risk of patented trees taking the place of native trees in the forests.”

One way to prevent genetic drift associated with migrating tree pollen is to engineer sterile trees. But even sterile GE tree farms are not without concerns. A forest devoid of pollen lacks dependent insects, beneficial or otherwise. A forest devoid of pine nuts may provide housing, but not food for squirrels. Likewise, the mill-ability of a tree is not a trait nature selects for, and trees across the globe have been highly successful at co-evolving with the fungi, birds, insects and mammals that live in their branches, eat their roots and peck at their bark.

The Animal and Plant Health Inspection Service, or APHIS, is entrusted by the U.S. Department of Agriculture (USDA) to determine the environmental and human safety of bioengineered crops prior to their release. Thus far APHIS has received 140 applications to field test genetically modified trees, the majority of which have been received in the last five years. Despite the fact that field trials of GE trees require an environmental assessment (EA), the USDA has approved 108 of the tests without requiring an EA. Only seven requests were denied.

Critics say this is a problem, citing how many GMOs slip through the cracks without governmental regulation. Numerous agencies have guidelines controlling the release of GMOs, but no single agency is responsible for regulating their release. This is especially relevant to trees, as a pine engineered to contain less lignin is not an obvious health hazard to humans (FDA), nor to livestock (USDA), nor an obvious threat to the environment (EPA). These altered trees can, and have, come into being without regulation.

Lack of federal oversight notwithstanding, critics say that because tree pollen ignores political borders, an international regulatory system might be more appropriate. For even if the United States were to strictly regulate the release of GE trees, test plots or plantations in Mexico or Canada could easily pollute native forests on this side of the border.
Genetic revolution?

Earlier this year, arsonists torched two nurseries, one in Oregon, the other in Washington, that were believed to harbor GE trees. While one nursery denied that it was conducting such research, the other admitted involvement in genetic manipulation of trees. These aren’t isolated cases, as tree plantations around the world have been reduced to rubble by people who believe that altering the building blocks of life is unacceptable. Europeans in particular have united against this budding technology, and the European Union has enacted strict guidelines requiring that all GE releases be registered with a central body.

The industry has responded to public pressure. International outcry against genetic tampering has forced the industry to stop referring to its work as the “genetic revolution,” and adopted the less ominous moniker, “biotechnology.” When concerns were raised about this name as well, the industry switched to the more ambiguous and less caustic term, “life sciences.”

Predictions from both pro- and anti-GE camps are that commercial planting of GE trees won’t begin before 2005, and perhaps as late as 2010. In the coming years, both camps will likely begin building their cases before the government and in the court of world opinion. Only time will tell if native trees will continue their unaltered evolutionary path. In the meantime, the remaining ancient trees will stand, as they have for millennia.


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