Ask the right experts
A book review titled "Redefining 'natural' in agriculture" makes some interesting points. I haven't read the book, which is about organic farming and transgenic crops, although I know both authors slightly from my years as a professor at UC Davis. The review notes that many people have strong opinions about agricultural issues even though they lack relevant expertise. Anthony Trewavas, the author of the review, suggests that even "being a scientist doesn't qualify you to advise on any subject except your specialty."
So what is his own specialty?
A quick check of Web of Science finds he has published substantial scientific papers on "Dynamic localization of calmodulin domain protein kinase (CDPK) and its relationship to calcium signaling in growing pollen tubes" and so on, so if I ever want advice on those topics, I'll know where to turn.
When he wanders from his field of expertise things get interesting, but not necessarily credible. For example, his recent paper on "Green plants as intelligent organisms" claims that
When provided with water only once a year, young trees learn to predict when water will be provided in the future and synchronize their growth and metabolism with this period only
How exciting! Learning in plants! Except that I looked up the cited book chapter and it doesn't show that. All of the trees in the experiment described were
watered to field capacity (27% vb/v) once per year, at the beginning of the growing season, to simulate natural patterns of water availability
In other words, the trees got water at the same time of year as their ancestors, so they didn't have to learn anything new. Instead, they just executed their DNA-based programs, shaped by past natural selection.
What is missing from Trewavas impressive publication list is original field research on environmental risks or benefits of biotechnology, pesticides, etc. If we want to know which pesticides cause cancer, we need to consult cancer researchers, not chemical engineers. Similarly, if we want to know about ecological and evolutionary risks of biotechnology, we need to consult ecologists and evolutionary biologists, not genetic engineers.
Fortunately, the Ecological Society of America, a stellar group of 8000 scientists who collectively publish a significant fraction of ecological research papers worldwide, has issued a public statement on risks and benefits of transgenic crops. Individual ecologists and evolutionary biologists have published on particular biotechnology related topics, but this statement is a balanced expert overview of issues that should be considered. They make a good case for a "cautious approach" while supporting "judicious use of biotechnology."
Trewavas suggests that risks of pesticides should be compared to risks from the natural chemicals plants make to defend themselves against insects, that wider use of organic methods could worsen food shortages, and that reduced tillage methods using herbicides can reduce erosion. I agree with each of these points, to some extent, but in each case there are other factors to consider. Watch for my book on Darwinian Agriculture, sometime in 2009. Go ahead, ask whether I have published papers with original data on both evolutionary biology and agricultural field experiments.