Supertrees to the rescue?
By Clive Chan

OTTAWA — What’s green, can grow in months, and can be harvested quickly for our use? With that description, chances are you didn't guess trees. In fact, scientists are working on trees with just those attributes.

A typical hybrid poplar plantation.

In light of the heightened social controversy over genetically modified foods, the bioengineering of trees is not a topic one often sees in the media. However, its potential to improve or harm life on this planet can be just as great.

The demand for the super tree

The paperless office the computing age promised has not materialized.Instead, affordable consumer printing technology has led to a torrent of paper use.

Although recycling has helped the situation somewhat, each office worker still uses an average of one kilo of paper a week.

Between 1970 and 1994 alone, consumption of paper products has increased 50 per cent in developed countries, and 300 per cent in developing countries.

Keeping up with our increased demand means harvesting our natural forests. Forestry in Canada is heavily regulated to be sustainable — designed to allow replanted trees sufficient time for natural regrowth.

Many forestry companies have adopted comprehensive codes of ethics and employ the newest methods in logging. Even so, environmental groups like Greenpeace and the World Wildlife Fund continue to urge the government to be more stringent on its harvest limits.

Enter the “super tree.” Geneticists propose that the key to many of humankind’s environmental problems lies in the tree’s genetic code. In their vision, the ideal tree would grow as fast as a weed, take in more than its share of carbon dioxide from the atmosphere, and produce desirable wood products, all while protecting our natural forests.

Can it leap over tall buildings as well?

Biotechnology – 10,000 years of history

The genetic manipulation of trees has existed for almost ten thousand years. Selecting trees with good traits and breeding them with others is a practice that has been common. Scientists can combine two plants to breed a third, but only with similar plants. This process, commonly known as genetic selection, is non-intrusive and natural.

Today's biotechnology can be quicker and even more selective. It allows scientists to combine multiple genes from multiple sources to create entirely new organisms.

In nature, it is highly unlikely that two similar species breed with one another; the process would take years, if it happened at all. Using genetic engineering, we can permanently insert genes into another organism.

Mapping the genome

Last September, an international team of scientists mapped the genome of the Populus trichocarpa, or the more commonly known Black Cottonwood. This poplar, being one of the more valuable trees sought by the pulp paper industry, also has a relatively simple genome. Regardless, the genome had more than 500 million characters and took two years and tens of millions of dollars to decode. Scientists hope that by unlocking the genome, we can modify characteristics of a tree to our liking.

Malcolm Campbell, a biologist at the University of Toronto, is part of the team that unraveled the genome for the Populus trichocarpa. The genome for the Black Cottonwood is not unlike a roadmap for future genetic research.

“Developing an understanding of the genome of Populus trichocarpa, and how that genome functions to give rise to a tree, will form the foundation of research for many tens of scientists for decades,” he says. “Having said this, there is already enough information available on individual genes to be able to make very precise changes to tree development.”

One area that Campbell looks at is the lignin in poplars. Lignin is a chemical compound that is an integral part of the cell walls of some cells. It is also what gives untreated paper that slightly yellow colouring. The bleaching process used to whiten paper to office standards is costly and harmful to the environment. Removing or reducing lignin in paper can remove or reduce the bleaching step. Lignin, however, also gives trees their strength and vitality. Without it, trees would bend and snap in stronger winds or become highly susceptible to pests.

Another area that is well understood is growth and reproduction. By making trees sterile, the spread of transgenic material to natural trees is curtailed, but can also cause trees to grow 30 per cent faster using energy diverted from reproduction.

Tree farming – the new agricultural frontier

Right now, in the Northwestern United States and British Columbia, there are farms that are cultivating poplar trees that takes up to 15 years to mature. These trees, while not genetically modified, are hybrid trees: produced through traditional breeding methods. The Canadian Food Inspection Agency (CFIA), under the Seed’s Act, regulates all genetically modified plants, including trees. Until recently, no genetically modified trees grew outside on Canadian soil. Armand Seguin’s pilot project in Quebec is the first to get approval to do so, albeit, under the strictest control.

Elsewhere in the world, tree plantations have sprung up since 1988, with a sharp increase in the last 10 years. In general, transgenic tree plantation trials in first world nations are conducted by university or government researchers while trials in Latin America, Africa and South-east Asia are conducted by the private sector.

Plantations with genetically modified trees were not seen as feasible before the end of the 20th century. Commercial use was curtailed by the inability of biotech companies to mass produce copies of genetically modified stock. Corporations such as Monsanto and Shell pulled out of their forestry ventures because they viewed it as unprofitable.

Early stages of transgenic poplars

The mechanization of a cloning technique called somatic embryogenesis has overcome this challenge. The Canadian Forestry Service played a significant role in discovering somatic embryogenesis.

This process differs from traditional cloning techniques in that it allows very large quantities of seedlings to be produced from very small amounts of plant tissue. The original specimen can be safely preserved in cryogenic freezers for reuse. In essence, scientists have created a photocopier for plant genes. Such a process is not limited to genetically engineered trees, but could also be applied to preserve tree species created through traditional breeding methods.

Jim Richardson of the Poplar Council of Canada says tree plantations are becoming more common as the technology matures. Hybrid-poplar (produced through traditional breeding) plantations in British Columbia are already gaining popularity, even though a lot of investment is needed initially.

Richardson says he has no problem with seeing genetically modified poplars produced in plantations.

“I prefer to see it as another agricultural crop, but it just takes a little bit longer to grow.”

Further recent mechanization of the process now allows corporations to create mass quantities of essentially cloned copies of trees. Diving costs and growing predictability will no doubt bring more corporations back onto the field of GM trees.

Looming concerns

Critics of genetically manipulated tree plantations say the danger of genes escaping into the environment is too great. In the past, introducing foreign species into a biosphere has had devastating results. As well, foreign species often thrive too well in new environments, causing the existing species to die out.

The destruction of biodiversity is the chief complaint made by environmentalists. They fear that the genetically modified trees would muscle its way into natural forests and replace a diverse environment with one of uniformity. They say this change could wreak havoc on food chains and ecosystems even beyond human comprehension or prediction.

Campbell disagrees with this assessment. He says people that make the argument that genetically modified trees will become invasive are basing their logic on food crop plants.

“[Crops] are bred to make seeds at the expense of making the woody part of the plant, and are therefore more likely to become weedy or invasive,” he says. “Trees aren’t like this.”

Campbell explains that genetic modification can control the speed of growth so that wood production precedes the flowering stage, effectively inhibiting reproduction. Trees may someday grow as fast as a weed, but that is where the two’s similarities end.

“The idea of a silenced forest, or a forest that is full of trees that will invade natural forests is based on a poor understanding of genetics, of tree biology, and of how trees are grown for the purposes of wood production.”

This distinction between food crops and trees is also indicative of why genetic engineering of trees is often misunderstood by the public. Since the alarm on genetically modified food was sounded in the late 1990s, other genetic research has been given a black eye, even though they are only minimally related.

In Canada, the biggest and most vocal critic of anything genetically modified is David Suzuki. The renowned environmentalist is also a geneticist, but he says scientists do not yet have a strong enough grasp on genetics to be making changes.

“Scientists ought to reflect a lot more deeply about the nature of their activity and be a helluva lot more humble,” Suzuki said in a recent interview. “What the hell is the rush to apply these half-cocked ideas based on very, very simple-minded notions of the way nature works?”

Conservationist David Suzuki doesn't think transgenic trees are ready for prime-time.

The David Suzuki Foundation is concerned about the unknown ramifications of exposing transgenic trees. Trees with built in herbicide tolerance, pest resistance and modified growth rates (the most common transgenic modifications), could have unknown effects if bred with wild trees. The Foundation does not think the scientists’ safeguards are sufficient in preventing the spreading and mutating of transgenic genes, known as genetic pollution.

A joint report by the World Rainforest Movement and the Friends of the Earth International in 2004 criticizes the effect of transgenic tree growth on soil. Increasing the speed of growth of a tree means greater demand on the soil and water in the earth, which means more area is required to service the new hungrier and thirstier. The report says geneticists are ignoring this factor when conducting their trials.

Stephen Nottingham, biologist and author of Genescapes: The Ecology of Genetic Engineering, agrees that not enough research about the impact on ecology has been done by scientists.

“Fast-growing transgenic trees will make additional demands on soil nutrients and water, with consequences for long-term fertility of the soils,” he says.

Some critics go further, saying GM trees will simply make keeping natural trees unprofitable and undesirable.

"The idea that intensively-managed plantations take pressure off natural forests is a myth,” said Sarah Tyack, of Friends of the Earth, in a press release. “What is happening is that natural forest is being cleared to make way for intensive plantations. GM trees will accelerate that process."

In May 2001, militant environmental activists caused $3 million U.S. damage to the University of Washington’s Botany department. The attack targeted the work of Toby Bradshaw, a geneticist creating genetically modified poplars. Although the research data was saved elsewhere, damage was also done to research into highly endangered species.

In the March of 2000, eco-terrorists destroyed more than 1,600 young trees in a provincial seed operation near Victoria B.C. A group calling themselves the Ministry of Forest Defense claimed responsibility, but it turned out that none of the destroyed trees and seedlings were genetically modified.

In the past six years, eco-terrorists have destroyed at least ten other GM tree trials in Britain, Canada and the United States. The Earth Liberation Front, a self-proclaimed “underground movement with no leadership, membership or official spokesperson,” has burned down offices and research laboratories in protest of genetic research.

While denounced by many other environmental groups, these actions have nevertheless attracted attention to the issue. Critics of genetically modified trees do not always have ecology in mind: many reject the idea based simply on moral, or theological ideals.

Are super trees our future?

Although the genetically modified tree industry is very much in its infancy, it is also growing at an alarming rate. In the north-western United States, field trials are currently underway with GM tree technology. The troubling factor is that other trials around the world, especially in Asia, are not held to high safety standards and are far less transparent. In China, a bold project that involved planting transgenic trees to stop the desertification of the Xinjiang region meant over a million transgenic poplars were planted. A further 400,000 were planted along the Yellow and Yangtze Rivers to reduce erosion. In 2003, due to the lack of controls and regulations, Chinese scientists reported to the UN that these trees are “lost” in the wilderness, its transgenic code flowing freely throughout the environment.

Industry insiders such as Campbell and Nottingham say they believe technologies are close to consumer use, with some aspects available now and some appearing within five years. The major hurdle is gaining public support for the projects and setting regulatory standards for the industry.

Campbell says though he sees much potential in genetic engineering, he does not see the use of such technology as a fix-all solution to environmental problems. He says each technology within the wide field of genetic engineering should be looked at for its own merit.

“Just as some medicines have different amounts of risk associated with them, the same is true for different applications of GM technology,” he says. “I am confident that when intelligent, open-minded individuals are presented with the facts, most will see the logic, the benefits and the lack of substantive risks associated with the deployment of GM trees.”

The genetic modification of trees sits in the grey area between good and evil. Right now, it is hard to say whether these genetically modified trees are the Superman or the Lex Luther for our world’s environment.