Points in brief:
- A recent peer-reviewed long-term analysis of North American and Western European staple crop agriculture provides evidence of sustained higher yields and lower pesticide use in Western Europe.
- Conclusion was that Western Europe has been able to better focus its innovation strategy on the kinds of biotechnology – both germplasm and crop management – that are needed to transition to a more sustainable high yield agriculture than has North America. A notable difference between strategies is the adoption of GM in North America but not in Western Europe.
- A non-peer reviewed blog article by David Tribe challenges a subset of the findings on the period 1996-2010. Here Chris Preston and the blog author argue that North American yields in GM maize and canola were comparable or superior to non-GM in Western Europe.
- The blog analysis is flawed because it is based on too small a number of years to be statistically reliable. This is clear when one includes the newly released data for 2011-2012 in their analysis and sees the significant impact one more year has on small data set used the Preston/Tribe findings. Further, the blog author cannot from the small dataset indicate what component of the normal annual yield gain comes from GM.
- The blog has not provided a convincing counter argument on yields, has not challenged the data on germplasm contraction in the US or the findings of better pesticide use management in comparable European countries.
In a recent peer-reviewed publication, we looked at yield and pesticide use trends in staple crops from two similar modern agroecosystems, North America (US and Canada) and Western Europe (region defined by FAOSTAT).
We analysed yield data in corn/maize, rape/canola and wheat, crops that are grown in both regions at large scales. Our findings were consistent for all three crops. Over the 50 year period we found that the “biotechnology package” (which includes options in germplasm improvement and management approaches) that comes from the Western European innovation strategies in agriculture result in higher yields than those achieved in North America. The robust trends indicate that this will continue. Yield improvement was not due to higher pesticide use because countries such as France have used comparatively less of both herbicides and insecticides per area under production than countries such as the US.
An obvious difference between the two regions is that the North American innovation strategy was compatible with a switch from conventional to genetically modified (GM) crops adopted in the mid 1990s. Western Europe has and continues to raise yields and reduce the use of pesticides without GM. A recent re-examination of our results reported by “Gmopundit” (aka David Tribe) on his blog challenges our findings that GM has been either ineffective at, or unnecessary for, achieving higher yields. He has not, however, attempted to refute our findings of lower pesticide use compared to modern agriculture practiced without the use of GM.
Tribe’s article shows graphs of maize and canola yields in the US and Western Europe for the years 1996 to 2010. For these short periods the linear regressions are marginally in favour of the US. It is well known that small datasets composed of data from arbitrarily selected years can be misleading because they by chance capture runs of years that contradict long-term trend lines. That is why our analyses used the entire dataset – to avoid bias from picking and choosing years to suit our argument.
To illustrate this, by picking a choosing a small number of years we can also change the outcome of Preston and Tribe’s limited analysis. By incrementally adding newly available data on US yields for 2011-12 and Western Europe for 2011 to their small dataset, the trends change again to Western Europe’s favour (Figure 1). This is why we based our analyses on the 25 and 50 year datasets that are available.