Why climate change matters to pest and disease management
President Donald Trump probably heard their buzz from his podium at the Rose Garden last week when he announced the United States’ withdrawal from the Paris Climate Accords. He may have seen a few scattered exoskeletons around the White House. And in a few weeks, he may even be subject to their stench.
They are the 17-year cicadas that have emerged around Washington, D.C. this year – four years earlier than their natural incubation period. Many entomologists are pointing the finger at climate change, believing that higher ground temperatures have sped up the cicadas’ underground development.
Luckily these cicadas do not present a real threat to agriculture, but many of their fellow insects do. And the development and distribution of those insects, as well as myriad diseases, fungi, and weeds, will also be significantly altered by climate change. Expect more of them, in more places, and for longer periods. Here is why:
Pests will develop faster: As a cold-blooded animal, insects’ growth and development is highly affected by temperature. With increased temperatures, insects will develop faster and emerge earlier in the season (like the cicada). And, with faster development, some pests will even have time to produce an extra generation of offspring each growing season.
More areas will become hospitable to pests and disease: With increased temperatures, areas previously too cold to support many pests and diseases will become hospitable to them. Researchers have shown that since 1960, hundreds of pests and pathogens are moving poleward (away from the Equator) at a rate of about 2 miles per year.
Diseases travel with extreme weather: Many plant pathogens can become windborne and travel over long distances via wind, hurricanes, or other natural phenomena. An expected uptick in extreme weather due to climate change will increase both the quantity and geographic reach of these pathogen carriers, potentially emulating Asian soybean rust’s arrival in the United States from Venezuela after hitching a ride with Hurricane Ivan.
Growers worldwide are already losing 20% to 40% of their crops to pest and disease despite spending more than $60 billion on pest and disease management. Their challenge will only get more difficult with the changes brought about by climate change – more pest and disease, in more places, and for longer periods.