While it seems a little early in the season for us, today is the much anticipated National Corn on the Cob Day! And what better way to celebrate the number one crop in the U.S. than by brushing up on where you might find your sweet corn of choice. But before we do that, it’s important to remember that sweet corn is different than field corn. And though that might seem like a trivial distinction, it’s a pretty fundamental difference.
For starters, field corn has a higher starch content while sweet corn has higher sugar content. They are also harvested at different maturity levels–sweet corn is harvested when the kernels are immature and field corn is harvested after it has dried out and the kernels have shriveled a bit, creating a dented appearance. It’s for this dented appearance that field corn is sometimes referred to as “dent” corn. If that isn’t enough for you, the U.S. Department of Agriculture (USDA) counts field corn as a grain and sweet corn as a vegetable. Confused yet? The fine folks at Kansas Farm Food Connection have provided a useful breakdown of the different types of corn for your reading pleasure.
Owing to its versatility, corn has a multitude of everyday uses, which might help explain why it is the top crop in the United States. In addition to ethanol and livestock feed, the Iowa Corn Growers Association notes that corn and its derivatives can be found in over 4,000 items sold at your local grocery store. Personally, we find corn on the cob to be the best use of sweet corn.
Another key difference between field corn and sweet corn? Only about 1% of all corn grown in the U.S. is sweet corn. So even though corn is a huge crop in the United States, sweet corn only makes up a tiny sliver of it. In fact, whereas corn is (or can be) grown in all 50 states, the National Agricultural Statistics Service at USDA reports 2019 sweet corn production in only nine states totaling 6.3 million hundredweight (cwt, or 100 lbs). By the way, field corn is measured in bushels–another difference! As an additional aside, we’re pretty sure that sweet corn is grown in far more than nine states. What’s more, much of the U.S. sweet corn is destined for processing–either canning or freezing. So the corn on the cob that consumers see in grocery stores nationwide is but a fraction of what is produced each year.
Before we let you go to enjoy an ear of your favorite ear of sweet corn on the cob to celebrate this special day, we should offer a final note about corn breeding. We’ll leave it to the Smithsonian Magazine to get you up to speed on modern corn’s beginnings as a grass called teosinte–just know that farmers started domesticating it about 9,000 years ago in Mexico.
In more modern times, early public investments in corn breeding gave way to what is now largely a privatized process. In an interview with Nature in 2016, Dr. William Tracy at the University of Wisconsin-Madison noted that at that time he was one of only two sweet corn breeders remaining in the public sector in the entire U.S., which we found somewhat surprising. This is down from around 30 breeders in the 1980s. Regardless, the results have been seriously impressive. In U.S. agriculture, the trajectory of (field) corn yields over time is oftentimes seen as the gold standard by other commodities. In a brief yet informative summary, Dr. Bob Neilsen at Purdue University examines the Historical Corn Grain Yields in the U.S. which is nicely encapsulated in this graph.
So whether you fire up the grill, boil some water, use the microwave, or have some other trusted preparation method, make sure you take some time today to cook up your summertime favorite corn on the cob, garnish it to your preference, and enjoy this underrated food holiday!