By Jesse Newman

CHICAGO--Soybean futures fell Thursday, sapping a days-long rally in prices for the oilseeds as forecasts for better South American weather boosted comfort over world production and supplies.

Wheat dropped while corn nudged higher.

Soybean prices declined, backing off a six-month high posted in the previous session as forecasts for drier weather in Argentina eased concerns over crop problems in that country, reducing optimism that crop shortfalls there would lead to a surge in U.S. export demand. Although heavy rains and flooding have recently drown some crops in Argentina, favorable weather is now expected to take hold until the end of the planting season, casting uncertainty over how big a bite recent wet weather may ultimately take out of the country's crop. Argentina is a major U.S. rival for soybean production and export healthy crops there can dampen demand for domestic supplies.

Profit-taking by traders after a four-day run up in soybean prices also weighed on the market, as did an increase in crop sales by farmers.

Soybean futures for March delivery slid 4 3/4 cents, or 0.4%, to $10.70 1/4 a bushel at the Chicago Board of Trade.

Corn prices edged higher, gaining to the highest level in more than six months. Prices for the grain were buoyed by commodity fund buying and speculation that U.S. farmers will cut their plantings of the crop this year while adding soybean acres.

Signs of renewed export demand also kept corn prices afloat. The U.S. Department of Agriculture on Thursday said private exporters had booked sales of 110,400 metric tons of corn for delivery to unknown destinations during the 2016-17 crop year.

CBOT March corn gained 1 1/4 cents, or 0.3%, to $3.66 1/4 a bushel, the highest closing price since June 29.

Wheat prices declined for the second consecutive session as traders booked profits after prices for the grain notched a more than six-month high earlier in the week.

CBOT March wheat fell 7 1/2 cents, or 1.7%, to $4.23 1/2 a bushel.

Write to Jesse Newman at jesse.newman@wsj.com

(END) Dow Jones Newswires

January 19, 2017 15:41 ET (20:41 GMT)

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