The U.S. Has One Crop to Rule Them All, and That’s a Big Problem
Farmers in the United States are growing fewer kinds of crops today than they were 35 years ago, which could reduce their ability to weather drought, pests, diseases, and other environment alchallenges, according to a new report.
Crop diversity has fallen as farmers across a large swath of the Midwest have switched to corn and soybean. Elsewhere, growing conditions and demand have dictated the emergence of a few dominant crops.
“When an area is low in diversity, or if you only have one crop, it’s almost like a garden,” said Jonathan Aguilar, water resource engineer at Kansas State University and lead researcher on the crop diversity study. “If a worm attacks the crop, it’s easy for it to spread. But if you have a different crop close by, you can defend against some of those pests.”
The crop study, published in the journal PLOS One, examined crop diversity from 1978 to 2012 and was a joint collaboration between Kansas State University, North Dakota State University, and the United States Department of Agriculture.
The study ranked crop diversity based on an index value for the number of crop species that were predominant. So if a region went from five dominant crops to three crops across most of the area and several minor crops in a small portion of the area, the researchers assigned an index value of three, counting only the major crops.
As advances in biotechnology led to more cold-tolerant varieties of corn and soybean, farmers in parts of North Dakota abandoned a variety of small grains, such as barley and spring wheat, that they had grown before.
Crop diversity in the heartland region—Illinois, Indiana, Iowa, Kentucky, Minnesota, Missouri, Ohio, and South Dakota—shrank to an index value of 3.06, meaning just three major crops are now raised.
Corn and soy are two dominant crops in the Midwest; they’re grown primarily to feed livestock and to make ethanol.
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“The heartland region had the worst shrinkage in biodiversity, because corn and soybean are very profitable,” said Aguilar.
On the other hand, in eastern Montana, severe cold weather has driven the choice of crops grown today, primarily wheat, barley, canola, and sugar beets.
The decline in crop diversity has made farmers more vulnerable to drought, heat waves, flooding, and other climate-change-related disasters, according to the report.
If, for instance, a farmer grows sorghum and corn and a drought hits, the sorghum will be more likely to survive because it consumes less water. But if only corn is grown, the farmer will risk losing an entire crop and the sole source of income.
The lack of crop diversity also harms soil health.
“When you’re growing only one or two crops, you will deplete the nutrients in that soil, which could lead to drastic crop failures within the area,” Aguilar said.
But the researchers had some good news. The Mississippi region has higher crop diversity today than it did in 1978—four major crops, compared with three before. California and Florida fared better overall compared with the rest of the country, with five dominant crops, even if they did drop from a peak of seven dominant crops during the 1980s.
What’s the next step?
“We need to assess crop management to see if it’s diverse enough to defend our food supply from pest attacks and danger,” Aguilar said.
Related stories on TakePart:
• Holy Cow! Crops That Use Even More Water Than Almonds
• How One Farm Is Growing Food and Biofuels While Helping to Save the Environment
Original article from TakePart
