Diabrotica virgifera virgifera beetle larvae (known as western corn rootworm) wreak havoc on maize, causing an estimated $1 billion of damage every year to US agriculture. Knowing that Heterorhabditis bacteriophora nematodes kill the pest, researchers in Switzerland have successfully improved the nematode’s response to a chemical, (E)-beta-caryophyllene, released by damaged maize roots, to attract the nematodes directly to the pest in a bid to produce an environmentally safe pesticide.