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Corn Silage for Beef and Dairy Rations – Eastern US

May 21, 2026

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  • Agronomists, nutritionists, and herders all contribute to creating and determining the best rations for a given situation.
  • Several corn silage products can be grown for feed rations depending on the milk productivity and weight-gain goals of the herd.
  • Harvest conditions, storage facilities, and quality analysis influence the corn silage feed ration.

Types of Corn Products Used for Silage Production

Flex-Acre Corn Silage Products

  • Flex-acre corn products are evaluated for silage yield, whole plant digestibility, and starch, as well as the agronomic characteristics that are important for both grain corn and silage production.
  • In addition to the above silage parameters, traditional tall corn silage products are often developed with disease tolerance and insect resistance traits in mind for the corn-on-corn silage acre.
  • New, short-statured Preceon™ corn products are also being developed for silage harvest. The dry matter yields, starch content, and digestibility of these short-statured corn products are comparable to tall-statured corn.1
  • Compared to brown midrib (BMR) corn, short-statured corn is similar in dry matter yields and starch content. Digestibility comparisons vary between corn products, and short-statured corn is comparably digestible to some BMR corn products.

The initial introduction of the breeding trait technology is targeted by geography in alignment with maturities, traits packages, and available supply. Bayer Crop Science looks forward to addressing broad acre demand through market expansion across the US and North America late-decade, with the introduction of the biotechnology trait.*

*Preceon™ Smart Corn System hybrids, developed through biotechnology, are not currently available for commercial sale or commercial planting. Commercialization is dependent on multiple factors, including successful conclusion of the regulatory process. The information presented herein is provided for educational purposes only and is not and shall not be construed as an offer to sell.

Preceon Short Corn product roll-out schedule

Brown Midrib (BMR) Corn Silage Products

  • Brown midrib corn products were developed from a naturally occurring mutation discovered in dent corn in 1924.2 Insect and herbicide traits have been incorporated to modify BMR corn products.
  • These corn products are named after the midrib/vein running down the center of leaves, as it appears brown instead of white.
  • The mutation causes the leaf tissue to contain immature lignin cells, which increases digestibility and rate of passage.
  • Brown midrib corn products are grown exclusively for silage production and are used to feed high-producing dairy cattle.

Enogen® Feed Corn Silage Products

  • Enogen® Feed corn was developed for the ethanol industry.
  • The alpha-amylase enzyme in the grain portion of the plant allows complex carbohydrates, such as starches and sugars, to be converted to more available sugars for digestion.
  • The improved carbohydrate digestibility is available right away, without requiring the entire ensiling process.
  • There are additional stewardship requirements for using these corn products to ensure that the end use of this corn remains in the cattle feed or ethanol industry.

Determining Whole Plant Dry Matter and Silage Corn Harvest Timing

Silage corn should be harvested at a moisture content that ensures good storage and complete ensiling in the type of silo that will be used (Table 1), so determining whole plant dry matter at harvest is critical for putting up quality silage for beef or dairy rations. The milk line (or starch line) in the kernel is often used to estimate whole plant moisture (Figure 1) to help make this determination, but it can be an inaccurate indicator. Incorrectly estimating whole plant moisture may cause a producer to put up the silage when it is either too wet or too dry, lowering its quality.3,4 Fortunately, there are several tools to help producers take more accurate measurements of moisture content: a microwave oven, a drying oven, or a commercial forage moisture tester.

However, to use any of these tools effectively, the tested sample must be a good representative of the whole field. Any estimate is only as accurate as the samples tested. Whole plant moisture can vary depending on changing crop conditions from one side of the field to the other, or whenever a corn product change occurs. Any samples tested should account for these variations.

Table 1. Target silage moisture for different storage structures.

Corn Silage targets by silage storage structure, plant moisture and dry matter

If silage is ensiled when it is too wet, it may ferment poorly and seep, removing nutrients—particularly soluble nitrogen and carbohydrates. Silage that is harvested when it is too dry can have air pockets that prevent anaerobic fermentation and allow mold to develop. In addition, kernels with too little moisture will be hard and less digestible.

Theoretical Length of Cut for Silage

Theoretical length of cut (TLC) balances fiber for optimal rumen function, packing, and fermentation.5 Adjustments to TLC are related to silage dry matter levels at harvest (Table 2). Drier silage benefits from a shorter particle length to aid packing and fermentation. Longer particle lengths are needed to supply effective fiber for rumen function when corn silage is the main roughage of a ration.

Table 2. Theoretical length of cut based on corn silage dry matter.

Length of cut based on silage corn dry matter


Various stages of corn silage milk line.]
Figure 1. The various stages of kernel milk line.

Silage Kernel Processing

Silage corn kernels are broken open and chopped into smaller pieces during processing, a step intended to make the corn more digestible by giving the microorganisms in a cow’s rumen better access to the starch. Improving digestibility improves starch utilization, which may increase feed efficiencies and even milk production.6 If processing is successfully increasing the digestibility of the silage, herders should see a reduction in the amount of starch being passed in the cattle’s manure. Manure can be tested to evaluate the amount of starch present.

Person handling corn silage evaluating feed quality
Figure 2. Although appearance and odor can help identify spoilage, a laboratory analysis is needed to determine feed quality.

Laboratory Analyses for Silage Quality

While there are well over 30 different analyses that can be performed by commercial feed testing laboratories, there are four analyses important for comparing silage quality differences and for formulating a balanced cattle ration.

Dry Matter (DM)

  • Dry matter is every component of the silage except water, which includes the protein, fiber, fat, and minerals. In other words, DM represents the total weight of feed minus the weight of water in the silage.
  • Harvest moisture is targeted at 63 to 68% for upright silos and 60 to 70% for bags.4
  • The target DM value is between 30 to 40%, depending on the moisture recommendation for the type of storage unit.

Neutral Detergent Fiber (NDF)

  • The residue or insoluble fraction remaining after boiling a feed sample in neutral detergent solution. The NDF is composed of plant cell wall components and some pectin.
  • It is a close estimate of the total fiber constituents of the silage since it measures cellulose, hemicellulose, and lignin. As NDF rises, animals consume less silage. Neutral detergent fiber generally increases with low-grain silage, stress, or immaturity and can be an inverse predictor of intake.
  • The target value is between 41.3 and 54.1%.6 Ruminants are expected to consume a capped total NDF near 1.2% of their body weight.7

In Vitro Neutral Detergent Fiber Digestibility (IVNDFD)

  • Measures maximum potential digestion of the NDF portion. An in-vitro measurement (incubated in rumen fluid for 12, 24, 30, or 48 hours).
  • Higher values are related to greater intake and more milk. Laboratory influences analysis, but a value less than the laboratory average indicates silage should be fed in lesser amounts. A greater-than-mean value indicates the silage can be fed at higher rates (a good option for early lactation cows).
  • Target value varies depending on the average of the laboratory. A one percent unit change from the laboratory average changes dry matter intake by 0.26 lb/day.8

Starch

  • A carbohydrate that is a polysaccharide composed of many glucose subunits and is a readily available source of energy.
  • Higher levels may be better but would also require ration adjustments to avoid digestive upset and low energy intake. Silage with greater starch has lower NDF. If fiber is limited, supplementing could increase the cost of feeding this silage.
  • Target value up to 35%.9 Lower values indicate poor grain fill on ears. Higher values indicate overmature kernels.
Cows eating corn silage dairy rations
Figure 3. Feed rations may need to be adjusted based on cow productivity and silage analysis.

Minimizing Silage Losses

The most important practices for minimizing silage losses are to:

  • Harvest at an appropriate dry matter content
  • Fill the silo quickly with appropriate packing
  • Seal silage containers well
  • Feed at an appropriate rate while maintaining a firm silo face during feedout

Sources

1[@UniversityofWisconsinExtension]. Kaur, H. 2025. Agronomic fit of short corn as a BMR alternative [Video]. The Agronomic Fit of Short Corn as a BMR Alternative
2Lauer, J. and Coors, J. 1997. Brown midrib corn. University of Wisconsin-Madison, Agronomy Advice. Field Crops 28.31-11. https://corn.agronomy.wisc.edu/AA/A011.aspx
3Lauer, J. 1999. Kernel milkline: How should we use it for harvesting silage? University of Wisconsin-Madison, Agronomy Advice. Field Crops 28.47-23. https://corn.agronomy.wisc.edu/AA/A023.aspx
4Jones, C.M., Heinrichs, J., Roth, G.W., and Ishler, V.A. 2004. From harvest to feed: understanding silage management. Pennsylvania State Extension. UD016. https://guelphdhmcp.ca/wp-content/uploads/2018/03/from-harvest-to-feed-understanding-silage_PennState.pdf
5Hutjens, M. [in Silva-del-Rio, N.] Opportunities to improve corn silage in California: Kernel processing and theoretical length of cut. University of California Agriculture and Natural Resources. https://ucanr.edu/sites/default/files/2011-02/74226.pdf
6Roth, G.W. and Heinrichs, J. 2001. Corn silage production and management. Pennsylvania State University. https://extension.psu.edu/corn-silage-production-and-management
7Garcia, A., Thiex, N., Kalscheur, K., and Tjardes, K. 2003. Interpreting corn silage analysis. South Dakota State University. ExEx 4027. https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1124&context=extension_extra
8Shaver, R. 2007. Evaluating corn silage quality for dairy cattle. University of Wisconsin-Madison. https://fyi.extension.wisc.edu/forage/evaluating-corn-silage-quality-for-dairy-cattle/
9Quality and feeding. In, Corn silage. University of Wisconsin. https://corn.agronomy.wisc.edu/Silage/

Web sources verified 4/28/26. 1210_90601

Disclaimer

Always read and follow pesticide label directions, insect resistance management requirements (where applicable), and grain marketing and all other stewardship practices.