Les Firbank鈥榮 small-farm childhood in Yorkshire led him to a degree in animal ecology, followed by a PhD at the University of East Anglia on the population dynamics of the corncockle, a rare arable weed, and a postdoc on weed management at the University of Liverpool. Next came a teaching job, combined with research that became a still-used classic, The Ecology of Temperate Cereal Fields. Then Firbank joined the Institute of Terrestrial Ecology, working on farmland biodiversity. He has been involved in the national Countryside Survey 2000, and in studying threats to Europe鈥檚 biodiversity. His current role is as head of land use at the Centre for Ecology and Hydrology.
Does the trial tell us anything about genetic modification as a technology?
Only in the most limited sense. We were looking at one set of impacts of three crops with one particular trait, herbicide tolerance, in one particular agri-system, in one particular society with its own priorities. The results don鈥檛 translate to other traits or to other parts of the world. But what we have done is demonstrate that questions can be asked on a case-by-case basis.
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The headlines claim the results show GM crops harm the environment. Are they wrong?
They are making a political point about GM.
But isn鈥檛 GM what it鈥檚 all about?
Right from the start we have always stressed that one of our biggest concerns is that our results would be over-interpreted. Scientifically all we are saying is that we have demonstrated the risk of environmental harm of one type of GM crop on biodiversity in one particular kind of ecosystem. In recent months, people have realised that the debate should not be driven by our results. We would say 鈥� dead right! We were looking at one part of a bigger jigsaw.
What a job to have had! How did you wind up as trials coordinator?
The short answer is my director told me to apply. We were one of two teams that tendered for the research. We鈥檇 had a lot of experience in handling the logistics and data required.
And how did you hear that the job was yours?
By phone. I was in the kitchen having a cup of tea.
And how did you react?
I just thought, yes!
You obviously won鈥檛 tell us how you think government should respond to your results, but do you hold strong feelings about this?
I can remember a period when I was a kid in Yorkshire when we had cowslips all over the farm. By the time I was 10 most of them had gone. We thought it was just one of those things. We had no idea it was because of the way we were managing the land. We had put too much manure on it. As a family we didn鈥檛 want to do any harm. That issue 鈥� how to balance farming and wildlife 鈥� has always driven my research interests. Other members of the team come from very different viewpoints. Some of the statisticians, for example, see this as a unique opportunity to design an environmental experiment properly and see it through.
Was there ever a time when you thought the trials would fall apart?
We never had any doubt. In many ways this was quite an easy experiment because the pressures were so high. In normal science, if you run into difficulties with resourcing the answer is always to go back and make the best of it. Here, our organisations realised that if we needed more people at a particular time then those people simply had to be found. The price of failing was far too high. Also, we鈥檝e had incredibly little turnover of staff 鈥� nobody wanted to leave. Oddly, I think the actions of some of the protesters helped foster a spirit of togetherness and a sense of how important the project was. We were carrying a lot of public money, a lot of public interest, to deliver science that was of as high a quality as we could do regardless of what was flying in from the side.
Did you ever meet any of the campaigners who were trashing crops? Did you get any hate mail? Did it get personal?
No. And I don鈥檛 think it did against any of the scientists. It did against some of the farmers, which was very, very serious. That was the worst part of the whole exercise. But even there, you are talking about isolated incidents. We had a lot of contact with protesters, especially in the early years when we did a lot of meetings, from big regional public meetings down to parish halls.
As for the actual trial, just how big was it? And how difficult?
We ended up counting about three-quarters of a million seeds and well over a million insects. I think we had something like a million plant records. For the seeds, we had to go out to 283 fields and dig soil cores in different parts of the field. In the first year at one site, it was so wet that there was as much mud inside your wellies as outside. We had to ferry the soil samples up to Dundee, where they had built special greenhouses in which it could be laid out on small trays and kept watered. Then you look to see what germinates, so people were counting the weeds as they came up. Then they had to be identified, which is quite difficult when the plants are only small. For the beetles, we set up deep pitfall traps 鈥� plastic beakers filled with preservative. In the lab, we floated off the animals and sorted out, say, the beetles from the spiders. The skills to identify the beetles are very specialised, so we transported the sorted samples to a station where we鈥檝e got these experts.
Didn鈥檛 we already know about field ecology? How does the trial compare with other studies?
It is way out on its own, mainly because of its size. There have been a lot of studies of changes in agro-ecology, but they have tended to be very restricted in the range of animals that can be looked at properly. If you look at a lot of the other research, it鈥檚 case studies. You can get some patterns out of that, but nothing like the rigorous information base you need to really develop models and a more quantitative understanding of ecosystems. The most surprising thing with these trials was the consistency of the effects we found from year to year and from one part of the country to another. No one has done an experiment with enough replication to tell that before.
Were there any other unexpected findings?
One big surprise was this consistent result we have about insects called springtails. Nobody has really looked at their ecology before because they are not easy to study or even identify. But they have a critical role in breaking down plant material and providing the soil for future years. It turned out that they were very sensitive to how the field was managed. Nobody had looked at this before. Late in the summer we had more springtails on all the GM crops. That鈥檚 because with GM crops the herbicide is applied later, so the plants are bigger when they die and there is more stuff breaking down.
Does this go against the message that GM crops are bad for insect biodiversity?
It鈥檚 a more subtle picture, and it will change. In conventional spring oilseed rape and beet there are usually plenty of weeds there, and in the GM crops after the herbicide is applied you get plenty of stuff breaking down so you get more springtails. But we also found fewer weed seeds produced with the GM varieties. If that鈥檚 typical, then in a few years鈥� time you wouldn鈥檛 have as many weeds in the field to start with. So there鈥檒l be fewer weeds on GM plots in future, and even if they are bigger, there will be less food for the springtails.
What is the most important result?
It鈥檚 that the use of the herbicides drives the whole system. When we started we weren鈥檛 sure about that. At the start I was happy to expect differences between weather from year to year, or between different soils, to have had a much bigger influence on our results than was the case. The fact that hanging the herbicides has an impact on biodiversity is actually a key finding. Another is that the crop you choose to grow can be as important as whether or not it is a GM variety. The worst crop we looked at for biodiversity was conventional maize (See 鈥淔arming 1, wildlife 0鈥�).
People may interpret what you say in two different ways: it is OK to grow GM, or it is appalling that we have introduced all these crops without testing them thoroughly. What do you want them to think?
That鈥檚 a judgement call, and the role of scientists here is not to push people down one road or the other but to provide high-quality data for that debate. This is critical to the whole debate on wildlife, not just the question of GM or not GM. One of the reasons we are so proud of what we are doing is that this is the first time anyone has tried to make that sort of environmental assessment before the changes come in. The trials were never going to give a clear-cut 鈥測ou must go GM鈥�, or 鈥測ou must not go GM鈥�. The farm landscape is more complex than that.
People are saying that the comparison between GM maize and conventional maize is invalid because the conventional maize was treated with atrazine, which is being phased out in Europe because of the harm it does. You say this is nonsense 鈥� why?
There was an important debate at the start about what the comparisons should be. We had a clear view. We wanted to use current farm management on those farms that may potentially adopt these crops. That ruled out organic farming because their guidelines do not allow GM. But we were also aware that farmers change their management over time. Pesticides come and go, new regulations come and go. So we gave the farmers the freedom to manage the conventional crops as they would under commercial conditions and were careful to audit that. It is inevitable that farm practices will evolve. What we are seeing is part of that evolution 鈥� the herbicide is being phased out. The press are saying that this invalidates the trials 鈥� but the reason they can say that is that the farm-scale evaluations tell you how important changing a herbicide can be.
Isn鈥檛 the message here that all herbicides are bad for biodiversity and we should move towards organic?
All farming systems involve manipulating biodiversity, because in the countryside you always have competition for sunlight. The sunlight can go into crops and be used for food and fibre or energy. Or it can go into natural ecosystems. There is a conflict of interest. You can鈥檛 avoid that. Ultimately, if we were having this discussion in five years鈥� time, instead of asking what is the impact of this technology on biodiversity, I would rather it was based on what kind of share we are seeking for wildlife in the landscape. You can increase the share within the field, do conservation in field margins, or you can follow the American approach where you have a division between areas for production and areas dedicated to biodiversity.
Given the range and complexity of the trade-offs, is it rational to have one feature, GM, dominate the debate?
In the long run, no. But what the GM issue has done is raise the whole question of the balance between agriculture and biodiversity to the point where policy makers and the public are taking it seriously enough to give scientists the time and resources to look at the wider issues in detail.
If the crops had been bred conventionally to have these herbicide-resistant traits, would the results have been any different?
No. All of our results can be explained on the basis of the herbicides that were used and the times that they were used in the season.
Have you opened a Pandora鈥檚 box? Will there be calls for every new crop variety, GM or conventional, to be tested at great expense?
There is clearly a balance to be struck between the need to regulate and making development so costly that it is never allowed to happen. One reason why the evaluations were so large is that we had so little information to start with. Some of the things we simply won鈥檛 need to measure again.
Now you have reported, is that the end? Will you just file the data away?
The experiment hasn鈥檛 finished. This is only the first round of reporting. For one crop, winter oilseed rape, we are still collating the data, and we have additional information from the crops we have already reported on. We should have the database together within six months or so, but even then, we will only have presented the broad brush results. Some of the effects need more subtle analysis, and we鈥檒l be doing work on that.
You鈥檝e been in the limelight for four years. Have you enjoyed it?
We have all enjoyed it, especially the younger scientists on the team, because so many people have been interested in what we were doing. Although the programme goes on, I suspect our 15 minutes of fame is now pretty much up and we will just go back to doing the science again. One of the best experiences of the whole thing was when the key authors were presenting the science at that wonderful lecture theatre at the Royal Institution in London. It鈥檚 the equivalent of a footballer playing at an FA cup final 鈥� one of those special things that happens to only a few people in their career. And it鈥檚 great!