ANKENY, Iowa (DTN) -- Dippy the farm cat and her offspring patrol Brock and Robin Hansen's farm near Baxter, Iowa, with one mission: Keep hungry, chew-happy rodents away from grain and equipment.

While Dippy is smart -- the calico was aptly named because of her white-tipped tail that looks like it was dipped in paint -- and a good mouser, Robin Hansen said even a good feline security force needs backup.

With harvest wrapping up and winter fast approaching, the Hansens will deploy a myriad of defense measures -- bait stations, scented repellent, sticky traps and live traps using peanut butter as bait -- near and in grain bins and machine sheds to keep mice and rats at bay as they find places to nest near food sources. The couple will also conduct reconnaissance missions to find and seal up holes that rodents use to get into places they don't belong.

If they didn't, Robin said the results can be costly in lost grain, expensive repair bills due to destroyed wiring and lost productivity if equipment is down as a result in the spring.

"Dippy definitely helps with rodent control, that's for sure, but we have to do more," she said. "Rats and mice can be big problems that you have to keep on top of."

Despite the best efforts of Dippy and the Hansens, rodents find a way. The blower for an air conditioner on a tractor stopped working in the field recently. After taking off a panel to investigate, they found a mouse nest with babies in the unit. The infestation wasn't the cause of the problem, but it reinforced that rodent defense is important.

"There's a lot of wiring to other components nearby that one mouse could have wreaked havoc on," Robin said.

Rodents cause millions of dollars in damage to field crops, stored grain and farm equipment each year, according to USDA. In addition, they are the major carrier for more than 60 diseases that are transmissible to humans, companion animals and livestock.

Stephen Kells, an entomology professor at the University of Minnesota who specializes in pest control on farms, industrial sites and homes, said a rodents' drive to survive makes them a costly nuisance for farmers.

"The teeth of mice and rats are always growing, so they need to gnaw on things to keep them in condition so they can eat," Kells said. "Rodents will chew wires as a result. They will also chew on wires going through a knockout on equipment to get into it to nest.

"Combines and tractors have a lot of wiring and fly-by-wire technology that can be costly to replace," he continued. "You want equipment that is going to start and run when you need it."

Grain is often an easy meal. According to the University of Nebraska-Lincoln research, adult rats consume about three ounces of food per day or about 50 pounds of grain per year. While stored grain does not provide the complete nutritional balance they require, it can make up a significant portion of the diet. Mice consume about 2 pounds of grain per year, which is roughly 2,600 kernels of corn. Severe rodent infestations can result in substantial profit loss. Feces and urine left by rodents can contaminate grain, introducing harmful microorganisms that can be harmful to humans and livestock, according to research published in the International Journal of Research in Agronomy.

Here are four tips to rodent-proof your farm:

-- Seal up openings. A rat can enter a grain bin through a space as small as a 1/2 inch, while a mouse just needs a 1/4-inch hole. "Take something like a pencil and go around looking for cracks and crevices," said Kells, noting if a pencil fits through the hole, a rodent can likely squeeze through it. "Seal it up using a combination of rodent exclusion mesh and black urethane foam that can by layered."

-- Keep the farm and equipment clean. Promptly cleaning up grain spills near bins and thoroughly cleaning machinery, removing debris and grain prior to storage, eliminates food sources.

-- Take a holistic approach. Use a variety of registered, labeled rodenticides in bait stations and traps to protect the farm from rodents.

-- Be proactive. "I know things are stressful at harvest, but by making a rodent protection plan early and taking steps throughout the year, you will be ahead of the game protecting the farm from unwanted pests," Kells said.

Learn more at https://www.dtnpf.com/… and https://www.dtnpf.com/…

More tips about minimizing grain losses at https://extension.umn.edu/…

Find a book about rodent management at https://www.usda.gov/…

Matthew Wilde can be reached at matt.wilde@dtn.com

Follow him on social media platform X @wildeagwriter

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