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Short corn can be planted more densely, increasing yields per hectare (aerial view, top), although the trade-off is greater risk from dry weather. Short plants also resist strong winds better. Regardless of density, short plants enable farmers to apply fertilizer or fungicide in late summer by tractor rather than by plane (bottom), potentially reducing environmental impacts.

In U.S. field trials, the short corn benefited from nitrogen applied later in the season when it would be harder to add to tall corn, Vyn, Below and colleagues reported in Field Crops Research in May. That could have environmental benefits. Scientists have reported that water quality near farm fields can improve 15% to 20% when some of the fertilizer is applied later in the season. That s when corn plants are enlarging their kernels and need it most, reducing the excess that can leach into groundwater or run off into streams. Excess nitrogen pollutes groundwater and causes algal blooms in lakes even as far away from the Corn Belt as the Gulf of Mexico. Making better use of nitrogen fertilizer may turn out to be the biggest benefit of short corn, says Kendall Lamkey, a corn breeder at Iowa State University.

Additional environmental benefits could accrue if short stature allows farmers to spray fungicides on mature corn plants from tractors rather than airplanes, which can lead to greater drift away from the fields, potentially exposing people and wildlife. Although downsides may yet materialize, Below says he s optimistic about the potential: I m convinced it s going to be more advantages than disadvantages.

For U.S. farmers, the prospect of greater yield may be the biggest lure. Stine Seed, based in Iowa, already sells short corn in the United States. Its varieties are not planted on a large scale, in part because Stine is a relatively small producer of corn seed. But Stine says its hybrids can exceed the yield of tall corn by up to 10% in optimal conditions.

Founder Harry Stine grew up on a small Iowa farm and started breeding corn and soybeans in the 1970s. Larger companies like Monsanto licensed the improvements he made in soybeans, making Harry Stine a fortune; now in his early 80s, he is Iowa s only billionaire.

In the company s early days, however, Stine had far less to spend on R D than the big seed companies. That cost-cutting led to an unintended breakthrough with corn. The standard practice with breeding trials was to plant corn densely, then thin the plots to give plants room to grow. Stine didn t have the labor to do this weeding, so he let all the plants live, then selected the corn from the plots that performed the best.

Over the years, this led to hybrids that were about one-third shorter than conventional corn. Their leaves are angled upward more, and the tassels are smaller, letting more light reach the lower leaves. Crucially, this means more plants can be grown per hectare, potentially increasing the overall harvest. I think Harry s onto something, Lamkey says.

On his family farm in north-central Illinois, Darron Judd has been growing Stine s short corn for several years. To get the recommended density in his fields, he had to modify his tractor to plant seeds in rows 38 centimeters apart rather than the standard 76 centimeters. The change was costly, but Judd likes the sturdiness of the short corn. It just stands great. He aims for 18 tons per hectare. The Illinois average is 13 tons.

Yet Stine Seed President Myron Stine says several factors have made it hard to win new customers for short corn. For example, farmers like to compare new varieties to what they re used to growing, he says. If they do this by alternating rows of short and tall corn, the shorter hybrid will not perform as well because it s shaded by the taller corn. Lamkey says another reason many farmers have been reluctant to plant corn more densely is that it forces them to bet on the weather: in a dry year, plants packed into a rain-fed field can literally run out of water. And Seth Murray, a corn geneticist and breeder at Texas A M University, notes that farmers have to buy more seed to plant densely offsetting some of the profit from higher yield.

For Bayer and Corteva, those hurdles may prove less daunting. Those two companies account for 70% of the U.S. corn seed market, and they have more resources to promote proper planting of short corn.

In Iowa, at least, they expect to find receptive ground. Farmers there have become hyperfocused on the risk of derechos, Lamkey says. Those who turn to short corn to reduce the risk of loss may reap other benefits, in yield and environmental protection.

Decades after wheat and rice were transformed in the Green Revolution, corn is getting its turn.