Geography isn't static. Rivers change course, mountains erode, and islands even disappear under rising seas.
The geography of farming and food changes, too.
For example, 180 years ago my home county in Illinois was the castor bean and castor oil capital of the United States.
Both titles, however, slipped into irrelevance as a new resource, crude oil, rose to dominate the lubricant business.
Today, fewer and fewer Americans have ever heard of castor beans or castor oil.
Those long-forgotten twins seem to have a modern equivalent.
Total US wheat acres peaked at 88 million (35.6m hectares) in 1981.
Last year, the most recently completed reporting year, total US wheat acres were about one-half of that, or 45.6m (18.5m hectares).
After 40 years of falling US wheat plantings and, now, fast-rising international competition for exports, don't bet on USDA's forecast.
In its just-published "Agricultural Projections to 2029," however, the US Department of Agriculture (USDA) forecasts wheat's decades-long slide will stabilize between 45m and 46.5m acres in the coming decade.
That estimate also comes with a warning: "U.S. wheat export growth is tempered by sustained price competition from Russia, Ukraine, and the European Union".
Translation: After 40 years of falling US wheat plantings and, now, fast-rising international competition for exports, don't bet on our forecast.
It's no surprise that the two biggest benefactors of wheat's decline are America's two biggest crops, corn and soybeans.
As David Widmar of Agricultural Economic Insights pointed out more than two years ago, almost 30m of wheat's lost 43m acres have been planted to corn and soybeans since 2000.
There are two critical (among other) reasons for the big switch: government ethanol blending mandates have fueled corn's rise and fast-growing soy exports, especially to China, have pushed soybean acres higher.
Both forces, however, are losing steam.
Increased use of electric cars and, and soon, trucks, has already flat-lined the once voracious US gasoline - and, in turn, ethanol - appetite and continued global competition in the soy trade is pinching US soybean margins towards break-even.
Trade war woe
The elective, sustained tariff war with America's biggest soybean customer, China, throughout 2018 and 2019 has added to that woe.
More troubling for US farmers is the unabated growth of their soy competitors, especially South America's biggest soy boy, Brazil.
Late last year, USDA's Foreign Agricultural Service noted that for the first time ever, "Brazil is forecast to overtake the United States as the leading soybean producer in the world during the 2019/20 season".
If accurate, the increase would boost Brazilian soy planting area to 112m by 2029, or about 22m acres more than the record US soy plantings in 2017.
Part of the explanation is American - our terrible weather in 2019 clipped the US soybean harvest nearly 20 per cent.
Another part, though, is Brazil's strong and steady rise in plantings.
Last July, the Brazilian Ministry of Agriculture forecast the nation's soybean acreage would balloon 25 percent in the coming decade.
If accurate, the increase of 23.5m acres would boost Brazilian soy planting area to 112m by 2029, or about 22m acres more than the record US soy plantings in 2017.
China's buys up big
A few days after that news hit global markets, Reuters reported that the chairman of China's largest food company, state-owned COFCO International, told Brazilian ag leaders that his firm wanted to increase its Brazilian soy imports by 25pc over the next five years.
More troubling, the COFCO boss added that his company would underwrite soy expansion on some or most of Brazil's undeveloped 25m hectares.
Americans don't usually talk about hectares, so when I did the math on how many acres are in 25m hectares I had to sit down.
A staggering 61.8m acres.
That number and the Chinese promise should finally dispel another myth too long at the center of US agricultural geography: Buy land because they're not making it anymore.
Well, "they" are making more of it, and many of those makers - Brazil, Ukraine, Russia, China among others - are poised to substantially alter American farm and food geography in the next 20 years.
In fact, they already are - just ask a wheat grower.
If you can find one.
- US agricultural journalist, Alan Guebert, grew up on a 300 hectare Illinois dairy farm and for three decades has written The Farm and Food File, a weekly column on US farm and food policy and politics published in 50 North American newspapers. Contact him at email@example.com, or on Twitter @AlanGuebert
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