Providing habitat for beneficial insects could help growers reduce pest control costs, according to a Michigan State University study.
Beneficials, such as ladybird beetles, eat crop pests, saving farmers an estimated $4.6 billion in insecticides, according to the study.
Some growers already plant refuge or habitat strips alongside crops to attract the beneficials.
But providing this type of habitat is only part of the answer, said Megan Woltz, a university doctoral student and co-author of the study that appears in the current issue of Agriculture, Ecosystems and Environment.
The other co-authors were university entomologists Doug Landis and Rufus Isaacs, both based in East Lansing.
In one trial, the researchers planted strips of buckwheat adjacent to soybean fields.
Although they found substantially more ladybird beetles in the buckwheat than typically in field edges, the beetles in the buckwheat did little to change populations in the soybean fields.
Ultimately, the researchers said, natural habitat proved more important.
The amount of grasslands and forests within 1.5 miles of the soybean fields influlenced ladybird beetle populations in the field.
These large expanses typically encompass multiple farms, suggesting that neighbors may need to work together to provide natural landscapes, according to the study.