Iowa Farmer Battles Today's Pests While Eyeing Tomorrow's 'Mean Sixteen' Threats

Fri, 12 Dec 2025 19:31:41 GMT

For Worth County, Iowa, farmer Sarah Tweeten, the list of high-priority agronomic threats isn’t a political abstract — it’s a harsh reality she deals with every season.

Farming with her parents, Brian and Julie, and her uncle Roger, Tweeten has been steering the partnership toward more resilient cropping practices since joining the operation in 2021. This includes shifting from conventional tillage to strip tillage and splitting nitrogen applications.

The changes are part of a broader mindset: Protecting yields today from weeds, disease and insects while aggressively preparing for the next generation of agronomic threats. This forward-thinking approach is what led Tweeten to Washington, D.C., earlier this week as a Farm Journal Foundation farmer ambassador to help introduce a new report: “ The Mean Sixteen: Major Biosecurity Threats Facing U.S. Agriculture and How Policy Solutions Can Help. ”

Today’s Battles and Tomorrow’s Warnings
Researched and developed by Stephanie Mercier, PhD, the report takes an in-depth look at 16 significant pest issues U.S. farmers face now or could realistically in the future.

Tweeten is already battling a couple of the problems that underpin the urgency behind the research. For example, Palmer amaranth (pigweed) is gaining ground in her fields and across Iowa. The pervasive broadleaf weed can drastically reduce yields, with studies showing corn yield reductions between 11% and 91% and soybean yield reductions of 17% to 68%.

“We’ve struggled with pigweed as it continues to establish more resistance to our herbicides in our toolkit,” Tweeten says.

Two additional agronomic issues the report details include:

1. Asian Soybean Rust. First detected in the U.S. in Louisiana in 2004, this fungal disease has spread to southern states like Georgia and Mississippi. Scientists warn that warming winters could enable its migration to the Midwest, adding to existing disease pressures.

2. Corn Ear Rot. It can lead to aflatoxin production, making corn unmarketable and posing risks to humans and livestock. Aflatoxin is an issue Pickens County, Ala., farmer Annie Dee says is an ongoing problem for corn growers in her area.

“If we have aflatoxin, it can be impossible to sell the corn,” says Dee, also a Farm Journal Foundation Farmer ambassador.

A more recent threat she references is the impact of Highly Pathogenic Avian Influenza (bird flu) on local poultry farms.

Since January 2022, HPAI has been confirmed in a commercial or backyard poultry flock in all 50 states.

(USDA)

“An important market for us is poultry feed meal, so that’s a constant worry. The trickle-down effect is if we can’t move our corn then we can’t meet our financial obligations,” Dee adds.

Despite agricultural R&D offering a high ROI — $20 in benefits for every $1 spent — the Farm Journal Foundation report notes public funding for ag research has been declining over the past two decades.

“Farmers urgently need sustained support for aflatoxin research and prevention because these risks threaten our yields, our markets and the trust consumers place in American agriculture,” Dee says.

U.S. public spending on ag research and development has been falling for two decades.

(USDA-ERS)

African Swine Fever Has ‘Devastating Potential’
Looking to the future, Tweeten says she is concerned about African swine fever (ASF) and its potential to impact crop farmers as well as hog producers. The highly contagious swine disease hasn’t been detected in the U.S. mainland, but it isn’t far away. ASF has been confirmed in the Caribbean countries of Haiti and the Dominican Republic, roughly 700 miles from Miami, Fla.

“Being a farmer from Iowa, where we have probably eight times the amount of pigs as we do people, an outbreak of ASF would be just devastating to our state,” Tweeten says.

Hogs are among the biggest customers for the corn and soybeans Tweeten and her family grow. If African swine fever were to shut down hog production or exports, it wouldn’t just be a blow to livestock producers – it would hurt the entire agricultural community, she contends.

Read about 5 livestock diseases that could impact U.S. food security and economic stability.

Food Security Is National Security
When it comes to justifying funding for ag research, Tweeten knows there’s competition for every federal dollar. But she believes agriculture deserves a front-row seat — not only because of its economic weight and impact on farmers, but because of its role in national security.

“There’s that argument that food security is national security,” she says. “If there’s one thing COVID made us aware of, it’s that a disruption to our food chain can be terrifying, quite frankly.”

The pandemic made consumers and policymakers more aware of supply chain vulnerability. In 2020, the shock to the supply chain came from a human disease and logistical bottlenecks.

(Sarah Williams Photography)

Next time, Tweeten says, the disruption could just as easily come from animal or plant disease — whether African swine fever in hogs, Asian soybean rust or some other pathogen in crops. She worries about scenarios where farmers could face a fast-moving disease or crop pest while critical tools are still hung up in regulatory delays.

Her message: Farmers need a full toolbox, not one that’s half-built by the time a threat arrives.

“Ag needs to be in a good position when these sorts of emerging diseases and pests come into the country,” she says, “to have the tools in our toolbox ready for farmers to pull out.”

About the Farm Journal Foundation
The Farm Journal Foundation is a farmer-centered, non-profit, nonpartisan organization established in 2010. It works to advance agricultural innovation, food and nutrition security, conservation, and rural economic development.

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Iowa Farmer Battles Today's Pests While Eyeing Tomorrow's 'Mean Sixteen' Threats