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Take precautions before feeding drought-stressed forage

Be sure to take steps to manage forage against nitrate toxicity in cattle.

Jennifer M. Latzke, Editor

August 16, 2023

3 Min Read
close-up of rows of corn
AVOID DROUGHT-BASED TOXINS: Before you chop that field of drought-stressed corn, make sure you take steps to avoid nitrate toxicity.fusaromike/Getty Images

According to the U.S. Drought Monitor, drought has moved into much of central and eastern Kansas through the later parts of July and August. And the corn and sorghum crops are feeling it.

That has many farmers considering harvesting their drought-stressed corn for silage. But before you fire up the chopper, you’ll need a plan to manage the crop safely for your livestock.

Bruce Ziegler is the Dairy Nutrition and Tech Services Manager for Hubbard Feeds, an Alltech company. He warns producers that drought-stressed corn silages may include elevated nitrates as well as molds and mycotoxins. And they require precautions.


Topping the list is the potential for nitrate toxicity. Ziegler explains that nitrates convert into nitrites in the rumen and blend with hemoglobin to form methemoglobin, which cannot carry oxygen in the blood.

To reduce the risk to your livestock, he suggests these tips:

  1. Wait to harvest 10 to 14 days after a significant rainfall since drought-stressed forages recently exposed to rain are more likely to have high nitrate levels.

  2. Harvest at 62% to 68% moisture content for adequate fermentation. Don’t be fooled, Ziegler advises; plant stalks can be deceptively high in moisture.

  3. Plan to ensile high-nitrate forages for at least 21 days. The ensilage process converts more than half of nitrates to ammonia, which can be safely used by the rumen. Ziegler reminded cattle producers that high-nitrate forage silages can produce higher levels of “silo gas” or nitrogen dioxide, so extra safety measures must be taken near storage facilities.

  4. Since nitrates accumulate heavily in the lower third of the plant, plan to chop the forage higher on the stalk and leave more standing in the field.

  5. Test your forages before feeding and adjust your rations accordingly.


Dorivar Ruiz Diaz, Kansas State University nutrient management specialist, along with Sandy Johnson, Extension beef specialist and John Holman, cropping systems specialist, also advise growers of considerations for baling and feeding high-nitrate forages in the Aug. 3 Agronomy eUpdate.

Again, test the crop before you cut the forage. Your aim is to provide a whole-plant sample to more accurately represent what the cattle will eat. You may want to mark areas of the field where there’s more stress and differing nitrate concentrations. Then, you can mark bales from that part of the field and segregate them in storage.

They advise grinding and mixing the feed with either prairie hay or brome, in order to dilute the total nitrates in the animal’s ration. And resampling and testing for nitrates and forage quality before you feed those bales is time and money well spent.

“While the nitrate concentration does not change after hay harvest, the variability of nitrates across a field and the challenge of collecting a truly representative sample preharvest make a thorough postharvest sample imperative,” Ruiz Diaz writes.

Cattle producers may be considering grazing high-nitrate forages, but the K-State experts warn that that can be a dangerous practice.

“Grazing pressure should be limited so that animals do not consume the parts of the plant forage testing shown to be dangerous,” Ruiz Diaz writes. “Although animals tend to consume the leaves and the top portions of the plant, which contain less nitrates, the risk of [animals] consuming a high-nitrate portion of the plant still exists. In addition, the longer the animal is left on a field and the more that animal is forced to eat the remaining forage at the lower portions of the plant, the greater risk of nitrate poisoning.”

To learn more, read the K-State Research and Extension publication "Nitrate Toxicity" online. Or visit hubbardfeeds.com/blog/drought-stressed-corn-silage to learn more.

Source: Kansas State Agronomy eUpdate and Hubbard Feeds contributed to this article.

About the Author(s)

Jennifer M. Latzke

Editor, Kansas Farmer

Through all her travels, Jennifer M. Latzke knows that there is no place like Kansas.

Jennifer grew up on her family’s multigenerational registered Angus seedstock ranch and diversified farm just north of Woodbine, Kan., about 30 minutes south of Junction City on the edge of the Kansas Flint Hills. Rock Springs Ranch State 4-H Center was in her family’s backyard.

While at Kansas State University, Jennifer was a member of the Sigma Kappa Sorority and a national officer for the Agricultural Communicators of Tomorrow. She graduated in May 2000 with a bachelor’s degree in agricultural communications and a minor in animal science. In August 2000 Jennifer started her 20-year agricultural writing career in Dodge City, Kan., on the far southwest corner of the state.

She’s traveled across the U.S. writing on wheat, sorghum, corn, cotton, dairy and beef stories as well as breaking news and policy at the local, state and national levels. Latzke has traveled across Mexico and South America with the U.S. Wheat Associates and toured Vietnam as a member of KARL Class X. She’s traveled to Argentina as one of 10 IFAJ-Alltech Young Leaders in Agricultural Journalism. And she was part of a delegation of AAEA: The Ag Communicators Network members invited to Cuba.

Jennifer’s an award-winning writer, columnist, and podcaster, recognized by the Kansas Professional Communicators, Kansas Press Association, the National Federation of Presswomen, Livestock Publications Council, and AAEA. In 2019, Jennifer reached the pinnacle of achievements, earning the title of “Writer of Merit” from AAEA.

Trips and accolades are lovely, but Jennifer says she is happiest on the road talking to farmers and ranchers and gathering stories and photos to share with readers.

“It’s an honor and a great responsibility to be able to tell someone’s story and bring them recognition for their work on the land,” Jennifer says. “But my role is also evolving to help our more urban neighbors understand the issues our Kansas farmers face in bringing the food and fiber to their store shelves.”

She spends her time gardening, crafting, watching K-State football, and cheering on her nephews and niece in their 4-H projects. She can be found on Twitter at @Latzke.

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