Short-stature corn could give dairy farmers another option for producing forage without sacrificing milk production.
Researchers at Michigan State University are studying corn hybrids bred to grow shorter than conventional corn while maintaining competitive yields and forage quality. Early feeding work has found promising results — cows fed a short-stature hybrid had greater dry matter intake, energy-corrected milk yield and milk protein yield than cows fed conventional corn.
Efstathios Sarmikasoglou, a research associate at Michigan State University, has been part of the research evaluating how these hybrids perform in both the field and the ration.
“Those hybrids have been bred just to be shorter,” Sarmikasoglou says. “They have not been bred to produce less lignin, so they are not comparable to BMR in this concept.”
The research is still developing, but short-stature corn is giving researchers another hybrid type to evaluate for dairy forage, particularly as they look at yield, fiber digestibility, cow performance and methane emissions.
What is Short-Stature Corn?
Short-stature, reduced-stature and dwarf corn all describe corn genetics resulting in a shorter plant. The MSU research has focused on hybrids carrying a naturally selected mutation known as brachytic 2, or br2.
The hybrids evaluated by Sarmikasoglou and his colleagues have a target height of about 7 feet, compared with 9 to 12 feet for conventional corn. The shorter plants also have several other physical differences, including smaller tassels, shorter distances between leaves, lower ear placement and thicker stalks.
The shorter plants also have several other physical differences, including smaller tassels, shorter distances between leaves, lower ear placement and thicker stalks. Sarmikasoglou says those traits can be useful in the field.
“These characteristics give [the plants] greater standability and more resistance to bending when high-wind gusts cross the plots,” Sarmikasoglou says. “They can also be planted at greater densities, and they are easier to access with ground equipment.”
The question for producers is whether those differences in plant structure also translate into differences in feed value and cow performance.
Short Corn Performs Differently in the Ration
Short-stature corn is not designed to be a BMR hybrid. BMR corn is specifically bred for lower lignin content and improved fiber digestibility, while short-stature hybrids are selected primarily for reduced plant height. Still, the short hybrids studied at MSU had lower lignin content than the conventional corn used in their trials.
Sarmikasoglou’s team first evaluated three short-stature hybrids in a 2023 feeding study, comparing them with conventional tall corn and BMR corn. The corn was planted in May and harvested in September at about 35% dry matter before being ensiled under similar conditions.
The first study was designed to identify the strongest-performing short hybrid. Cows received diets containing silage from one of the three short hybrids, conventional tall corn or BMR corn. Researchers formulated the diets at about 24% forage NDF and fed the cows through three-week periods.
The short hybrids increased dry matter intake and milk production compared with conventional tall corn, although the researchers did not see a difference in feed efficiency. BMR produced a different response. Cows fed BMR had lower intake and milk production but greater milk production per unit of feed.
Sarmikasoglou says several factors could have contributed to the unexpected BMR response, including the cows’ stage of lactation, potential mycotoxin differences and growing conditions.
“We didn’t test for mycotoxins, but that was one of our suspicions,” Sarmikasoglou says.
Growing conditions also may have played a role. Michigan experienced a relatively dry spring and growing season in 2023.
“We thought the dry conditions may have been one other reason we didn’t see the full potential of the BMR,” he says.
Fiber Level Influences Methane
After the first study, researchers selected the short hybrid with the strongest combination of animal performance and field yield for a follow-up trial. This time, the team compared the short hybrid with conventional tall corn in diets formulated with different NDF and starch levels.
The study included diets with either 25% or 31% NDF and different starch concentrations. As expected, higher-starch diets increased dry matter intake, milk yield and milk protein content.
The short hybrid also performed well.
“We found the short hybrid increased dry matter intake, energy-corrected milk yield and milk protein yield compared with the tall corn,” Sarmikasoglou says.
Researchers also measured methane emissions. The hybrid type did not affect methane emissions, but dietary fiber did.
“We didn’t see an effect between the hybrids,” Sarmikasoglou says. “As expected, the high-fiber diets resulted in greater methane emissions, methane intensity and methane yield.”
Sarmikasoglou notes the finding fits with previous research showing a relationship between higher dietary fiber and methane production. For farmers and nutritionists, the lack of a methane difference between the corn hybrids adds another piece to the evaluation. Short-stature corn did not appear to increase methane emissions compared with the conventional tall hybrid in the study, while diet formulation continued to influence emissions.
“It seems promising to use short-stature corn for grain and forage on dairy farms. However, we still need more data before we can make recommendations.”
Yield Still Needs More Study
Positive cow performance only goes so far if a corn hybrid does not produce enough feed per acre.
In the MSU animal trials, the short hybrids produced between 7.5 and 9.3 dry matter tons per acre. Researchers had one plot per hybrid, so Sarmikasoglou cautions against using those numbers as a broad yield recommendation.
Other MSU agronomy researchers are also evaluating hybrids carrying the same mutation. In comparisons with conventional tall hybrids, they have observed similar yields, with no significant yield response from increasing seeding rates.
The early results are encouraging, but more field data is needed across different environments and growing seasons.
“It seems promising to use short-stature corn for grain and forage on dairy farms,” Sarmikasoglou says. “However, we still need more data before we can make recommendations.”
Weather is one reason more research is needed. Temperature, precipitation and soil conditions can all influence corn performance, making multiple years of data important when comparing short and conventional hybrids.
What Should Producers Consider?
For dairy farmers interested in trying short-stature corn, Sarmikasoglou says the first consideration should be yield.
“First, producers should check yields,” he says. “If the quality [of short stature corn] is better, a 10% drop in yield may still be worth it.”
The decision also depends on the rest of the farm’s cropping and feeding system. Farmers should consider weather and soil conditions, how much land is available for growing corn and the availability of other fiber sources when deciding which hybrid fits their operation.
More Data Could Put a Higher Value on Short Corn
The next step for the MSU research is moving beyond animal performance and yield comparisons to determine the economic value of short-stature corn.
Researchers want more information on how consistently the hybrids perform across growing environments, how yields compare with conventional tall corn and whether the animal performance results can be repeated.
“We want to generate more data on these hybrids, including yield per acre compared with tall corn and the repeatability of the hybrids in dairy cow performance,” Sarmikasoglou says.
Ultimately, researchers want to put an economic value behind the decision to plant short-stature corn.
For now, the research gives dairy producers another corn hybrid to watch. Short-stature corn has shown promising results for intake, energy-corrected milk and milk protein yield, while field researchers continue to evaluate whether the hybrids can consistently deliver competitive yields.
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