Rainy Days Wash Pests Away

October 26, 2009

WORLD WAR II was raging around The Netherlands from 1941 to 1944. But in Zeeland province entomologist D.J. Kuenen slogged on with his solitary, long-term studies of climate and rainfall effects on fruit tree red spider mites in apple and plum orchards. Even under the best conditions in peacetime, long-term ecological field studies that could aid in natural pest control are few and far between. The reason is simple: longterm ecological field studies are an expensive, labor-intensive, problematic way to advance a career in academia. The more-assured path to tenure and gainful employment is a series of quick, narrowly-focused lab studies yielding a plethora of speedily published papers in scholarly journals.

DDT and the synthetic pesticide era, along with high-yield chemical farming, exploded in the years immediately after World War II. The tedious years of meticulously gathered data on natural pest control from wind and rainfall (a form of overhead irrigation) was consigned to languish for decades under layers of library dust in tiny articles in obscure journals. Kuenen and his predecessors studying the pest control efficacy of wind and high-pressure water sprays were several decades ahead of their time. Much like the monk Gregor Mendel’s now-celebrated genetic experiments growing wrinkly and smooth garden peas.

Today, the pendulum is swinging back to more natural forms of pest control. Kuenen and his Roaring Twenties predecessors studying wind and rain as natural forms of pest control would be warmly welcomed at sustainable agriculture gatherings today. Ecological field studies showing that heavy rain showers and wind storms blasted away 90% of pesky spider mites would be spurring graduate students and inventive farmers to simulate the natural pest control benefits with artificial wind and water blasts from hoses, sprinklers, and other devices.