There was an emerging opinion among analysts and traders that the markets might have already seen their highs, with Chicago Board of Trade corn futures tumbling nearly 8 percent this week and soybeans falling about 3 percent.

For the month of October, though, corn is up 6 percent and soybeans up 6 percent. Much of the gains were fueled by the inflow of managed money, a weak dollar and harvest delays.

Two private crop forecasts next week, from FC Stone and Informa Economics, should give the markets price direction, with some traders leaning toward the two firms raising their corn and soy production estimates from their October outlook.

The U.S. Department of Agriculture will issue its November crop supply and demand report on Nov. 10.

Among those who believe the CBOT grain markets have hit their peaks is Rich Feltes, analyst with M.F. Global.

“The markets have topped out for now,” he said, adding that daily reports from the Midwest are showing “phenomenal yields”. “Our view is big increases in (production) numbers will erode these markets. They are back-tracking and working lower.”

‘Lousy Harvest’

“These markets are certainly acting like they have all the bullish implications of lousy harvest conditions fully factored into prices,” agricultural commodities advisory company Brock Associates wrote in a note to clients on Friday. “The price action has many the markings of a top,” it said.

Chicago Board of Trade corn for December delivery settled 13-1/2 cents, or 3.6 percent, lower at $3.66 per bushel. November soybeans fell 7-1/2 cents, or nearly 1 percent, to $9.78.

Futures were also weighed by a rebound in the dollar against a basket of currencies as investors exited the stock market for the safe haven of the greenback.

Traders and analysts said the grain markets will get more direction next week from harvest progress, currency and energy markets and speculative fund flows.

“Outside factors will still be present. We could see good harvest progress and some liquidation from trend-following funds...some defensive play,” said analyst Shawn McCambridge of Prudential Bache Commodities.

“Markets are down today because there is going to be a window for farmers next week to harvest their crops,” he said.

U.S. farmers are forecast to harvest the biggest ever soybean crop this year along with the second largest corn crop, but incessant rains have slowed the pace of collecting them.

“Corn has gone from heading below $3 per bushel to rallying strongly because of the harvest delays,” McCambridge said, adding that the inflow of fund money also fueled the rally.

Traders and analysts were growing concerned about U.S. corn export sales, lackluster the past two weeks due to higher prices. A bumper crop in the fields and stiff competition from cheaper feed wheat added to the concern.

Sluggish export demand for U.S. wheat has kept prices under pressure as the market continues to digest high stocks after big crops in the northern hemisphere for the second straight year.

“If economic news calls for the market to rebound, (wheat) fundamentals remain heavy as underlined by the new IGC report,” French consultancy Agritel said in a note.