US farmers face plague of pests as global heating raises soil temperatures

As the climate warms in the US, agricultural pests that eat key food crops are moving northward.

The corn earworm is one of the most common farm pests in the United States. It is not known to survive in states beyond a latitude of 40 degrees north, but that is changing as soils warm and it spreads to new areas.

The University of Washington found that 2C of warming would increase the number of insects and cause them to destroy more wheat and maize than they do now. The harvests of staple crops in Europe are down this year due to heatwaves and the lack of rain.

Food security can be affected by pest invasions. The co-author of the book said that the overwintering zones are likely to shift northward. There is a canary in the coalmine.

It is important for agricultural producers to understand what is happening with the corn earworm. The fall armyworm is one of the pests that could spread northward in the US.

The southern range of the US is where corn earworms can survive winter, while the transitional zone and northern limits are where they can't.

The warmer winter soils meant that insects were more likely to survive. Researchers used four decades of soil temperatures and data to predict the distribution of pests.

New Zealand's wallaby plague is getting worse.

The southern range has grown by 3% since 1981 and is predicted to double in size by the end of the century. If the weather is good, corn earworm moths are able to spread quickly.

The model shows that this insect can expand its range into the US maize belt in Ohio, Indiana, Illinois, Missouri and Iowa. The models suggest that the whole state of Minnesota will be in the transitional zone by the end of the century, despite no corn earworms surviving its harsh winters.

Increased use of pesticides is possible. If intensive maize production does not shift north with changing climate, we expect that corn earworm will become a more frequent and important problem in these states.

He said that organic growers have a major challenge controlling this pest.

The report suggests that monitoring soil temperatures can help predict the spread of pests. Huseth wants to come up with a better forecasting tool for this pest and a risk-prediction model to give growers better information about pest spread. Both costs for farmers and pesticides could be reduced by this success.