Corn Sinks, Wheat Holds as USDA Stocks Rattle Grains
Key Facts
- Corn slid to a five-week low on Wednesday, September 30, as the USDA’s grain-stocks report showed old-crop supplies above market expectations, with December futures dropping 21¼ cents to US$5.00¾ a bushel.
- The corn-tracking fund CORN settled at US$18.98, a decline of 0.32% for the Thursday session.
- Soybean inventories offered support after the USDA pegged US stocks at 315 million bushels, below the 323 million expected, but China’s tariff kept a lid on gains.
- The soybean tracker SOYB closed at US$27.20, down 1.13%, reflecting the drag from China excluding soybeans from tariff reductions.
- Wheat bucked the trend with the WEAT fund rising 0.61% to US$24.72, helped by European prices reaching a one-week high.
- Argentina’s corn crop faces stress with 70% of the core planting region short of water, while Brazilian soybean planting at 3.4% runs slightly ahead of last year.
Today’s Focus
The grain complex split on Thursday, October 1, 2026, a day after corn futures sank to a five-week low. The USDA’s grain-stocks report on Wednesday, September 30 revealed more old-crop corn in storage than traders had expected, just as the US harvest accelerates.
Soybeans fell more modestly. The market found some support from a tighter-than-expected inventory number, but China’s decision to keep a 10% duty on American beans while cutting tariffs on corn and wheat reminded buyers that Brazil remains the preferred supplier to the world’s largest soybean importer.
Wheat was the outlier, edging higher as European prices touched a one-week high and the market digested the same USDA report with less urgency. The Chicago wheat tracker closed in positive territory even as corn and soybeans slipped.
What matters today. The USDA stocks report has reset expectations for US supply, but the bigger question for Latin American exporters is whether China’s tariff stance will keep Brazilian soybeans at a premium and sustain Argentina’s corn and wheat flows.
01 The session in one read
Thursday, October 1, 2026, extended the corn pullback that followed Wednesday’s USDA stocks report, but the grain complex was far from uniform. The corn-tracking fund CORN settled at US$18.98, a drop of 0.32%, while the soybean tracker SOYB fell 1.13% to US$27.20.
Wheat moved the other way. The WEAT fund rose 0.61% to US$24.72, supported by firmer European prices and a late session turn in Chicago wheat futures.
The session confirmed that US harvest pressure is real, but the deeper story is China’s selective tariff policy. By excluding soybeans from its latest round of tariff cuts, Beijing has kept a structural advantage for Brazilian beans just as the South American planting season begins. The variable to watch is whether Chinese state buyers resume active soybean purchases after Golden Week ends on October 7.
02 The board
The pressure on corn and soybeans came from the USDA grain-stocks report of Wednesday, September 30, which landed above market expectations for old-crop corn. December corn futures dropped 21¼ cents to US$5.00¾ a bushel that day, a five-week low, as traders reassessed just how much grain remains in US bins.
November soybean futures slipped 4¾ cents to US$12.93 a bushel on Wednesday. The decline was smaller because US soybean inventories came in at 315 million bushels, below the 323 million expected and down 3% from a year earlier.
| Asset | Level | Change |
|---|---|---|
| Soybeans (SOYB) | US$27.20 | -1.13% |
| Corn (CORN) | US$18.98 | -0.32% |
| Wheat (WEAT) | US$24.72 | +0.61% |
Source: RT close, 2026-10-01. Where a commodity has no spot feed, an exchange-traded tracker or leading producer is shown as a labelled proxy.
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03 What moved it
The USDA report set the tone. Corn stocks above forecasts caught the market leaning bullish, and the approaching US harvest added to the downward push.
China was the other major driver. Beijing excluded soybeans from tariff reductions announced on September 28, leaving US beans subject to an additional 10% duty while corn and wheat received relief.
That distinction matters enormously. Chinese state buyers Sinograin and COFCO had bought more than 12 million tonnes of US soybeans, but the tariff preserves Brazil’s price advantage in China, the world’s largest soybean market.
04 The Latin American read
For Brazil and Argentina, the session reinforced their structural position as the world’s export engine. Brazilian soybean planting reached 3.4% of expected area by September 24, slightly ahead of the 3.2% pace a year earlier, according to AgRural.
Argentina’s corn story is more difficult. Planting in the core region reached 55% of intended area, down from 60% a year earlier, while about 70% of the region faced water shortage or drought, according to the Rosario Board of Trade.
Argentine corn shipments to China have expanded rapidly, helped by export prices averaging US$10–15 per metric ton below competitors. Argentina’s 2026/27 corn exports are forecast at 39.5 million tonnes, with wheat exports seen at 14.5 million tonnes.
05 The names to watch
The three grain tracker funds are the cleanest way for foreign investors to follow this market. SOYB, CORN and WEAT each trade in US dollars and move with the underlying Chicago futures contracts.
The China holiday calendar is also a factor. Mainland markets were closed from October 1 through October 7 for Golden Week, reducing immediate visibility on Chinese buying activity for the next several sessions.
06 The outlook
The path for corn depends on whether the US harvest continues to reveal larger old-crop supplies. For soybeans, the next signal will come when Chinese buyers return from Golden Week and show whether the 10% tariff is actually steering demand toward Brazil.
Wheat is likely to remain the most independent of the three, with European price action and Black Sea flows setting the near-term direction. Argentina’s dry corn belt and Brazil’s early soybean progress are the Southern Hemisphere wildcards.
07 What to watch
- China’s post-holiday buying: Whether Sinograin and COFCO resume active US soybean purchases after October 7 will set the tone for the next leg of the soybean market.
- US harvest pace: Faster-than-expected corn harvesting could deepen the five-week low in corn futures and test the resolve of the corn bulls.
- Argentina weather: Drought across 70% of the core corn region threatens planting completion and could tighten Argentine exportable supplies later in the season.
- Brazil soybean planting: The slight lead over last year’s pace suggests a normal start, but uneven rains could slow the advance and affect the safrinha corn window.
Frequently Asked Questions
Why did corn fall so sharply this week?
The USDA grain-stocks report showed old-crop corn supplies above market expectations, sending December futures to a five-week low of US$5.00¾ a bushel on Wednesday, September 30.
Why did soybeans fall less than corn?
US soybean inventories came in at 315 million bushels, below the 323 million expected and down 3% from a year earlier, giving the market a cushion.
What is China’s tariff position on US grains?
China excluded soybeans from tariff reductions announced on September 28, keeping a 10% duty on US beans while granting relief to corn and wheat.
How are Brazil and Argentina positioned?
Brazilian soybean planting is slightly ahead of last year, while Argentina’s corn region faces drought and a slower planting pace, with 70% of the core area short of water.
Market data: RT
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