pesticides and EU regulations part 2: interview with Merf on alternatives

If the EU does indeed limit the use of pesticides in farming in Europe, as is currently being proposed, there will be a number of consequences.

The positives and negatives of these consequences depend upon where you are placed in the agri-food system.

The price differential between organic and conventional may decrease. This would have the effect of leveling the playing field between organic and conventional for the ultimate recipient of food, the consumer.

Consumer confidence in the food system in general may increase, as the consumer currently dislikes pesticides, and at the same time distrusts farmers, supermarkets and food manufacturers.

One consequence that may not begin to happen in Ireland, but which should as a matter of urgency, is the development of alternative approaches to pest and weed management.

This should include not just methods similar to those used in organic farming, but methods from the broader gamut integrated pest and weed management offer.

An expert on these options is UCD�s Dr. Charles Merfield. Merfield, or Merf as he�s more often known, is an organic cropping agronomist. He has helped develop a number of innovative approaches to weed and pest control, and has some interesting ideas on how we should go forward in this area.

�Up to now, the main way to control pests and weeds has been through the use of synthetic biocides, which are more commonly referred to as chemicals. However a more integrated approach is needed. All four sciences of the natural world should be utilized, that is physical, biological, ecological as well as chemical�.

He also points out the fact that �there is an immediate and looming problem for the industry. One set of controls are being taken away, but the replacements are not in place yet.�

He suggests that an integrated approach is more effective than a chemical only approach, while also have the bonus of being more sustainable.

Merf is concerned, however, that enough research into integrated approaches is not being done for the Irish situation. Worryingly he says that well functioning integrated management systems can take between 5 to 15 years to develop (similar to chemicals) �which for poses a major problem for Irish agriculture as chemicals are being lost right now, so integrated solutions are needed now�.

There are many lessons and techniques to be learned from organic farming: �organic weed management mostly uses physical and ecological techniques. Agro-ecological approaches such as cover crops are also viable options.�

Globally, according to Merf, those investigating alternative mechanisms for pest management have made more progress than those investigating weed management.

�Fifteen years ago, weed science journals were focused on chemical solutions. That�s changed in last ten years or so. There has been a rapid increase in herbicide resistance globally, which we haven�t seen as much here in Ireland�

He cites the case of the caterpillar in New Zealand. By simply providing the catterpillar�s parasitoids with extra food in the form of buckwheat flowers, a cheap, effective, safe and certainly image friendly option has been developed for the countries� wine industry.

Along with a business partner in his native New Zealand, Merf has developed a company promoting particular machines for physical weeding. These include direct fired steam weeders, flame weeders, the Four Wheel Hoe (pedestrian hoe), and false seed bed tillers (cultivators).

The business, called PhysicalWeeding, promotes what it calls the false and stale seedbed approach. This is done by creating a planting tilth but then delaying planting. The weeds germinate and/or emerge before the crop, to then be killed either by further tillage, thermal weeding or herbicides.

While there are solutions, problems remain. �even within organic approaches, there are pests and diseases that are difficult to control or the solutions are not so easy - carrot root fly crop covers are a pain. A biological control that could be applied by spraying would be much easier, but we need to look�.

Which prompts the inevitable question: will the agri-food sector in Ireland have the vision to look for this and other solutions, or will it try to continue down the ever more fraught path of business as usual?

(Pictured: Merf flogging a hoe at an organic conference. For more on the irrepressible merf, click here)