The January contract closed 3 cents up at $5.88-1/2 per bushel and November was 4 cents firmer at $5.78-1/4. Trade see-sawed as the January initially fell 5 cents, finding support at $5.80-1/2 per bushel.
Light speculative buying surfaced at that level until the lead month surpassed its 50-day moving average of $5.89-1/2, climbing to $5.92.
Funds bought about 2,500 contracts; Tenneco and Fimat Futures each bought 1,000-1,500 January. Commercials were net buyers.
"It seemed it was just evening up ahead of the report. Everyone is wondering if we'll see 11 (billion bushels) in corn and 3 (billion) in beans," said one CBOT floor broker.
Both estimates would be higher than USDA's October projections. An average of analysts' estimates pegged this year's US soyabean crop at 3.024 billion bushels, above the USDA's forecast in October for 2.967 billion.
If realised, that would be the second largest soya harvest in US history. An analyst average for US 2005/05 soya ending stocks was 317 million bushels, up from the USDA's October forecast for 260 million.
Firm cash markets were supportive. Cash prices on the southern portion of the Illinois River reached a point where they were stronger than the futures delivery equivalent, CBOT traders said.
In fact, November deliveries lightened to 37 contracts on Wednesday. A RJ O'Brien customer was the key stopper of 36 lots. CBOT soya registrations were unchanged at 1,790 lots late on Tuesday.
Pressure stemmed from concerns about a lagging export pace. US soya exports are behind a year ago; and with the spread of bird flu in Asia and Europe, concerns are mounting that global soya demand could be off as farmers cull flocks.
But there's also hope US meat exports could increase, thus increasing domestic soya use for pork and poultry feed. There was floor talk that China bought two cargoes of US soyabeans overnight.
The market was turning its attention to South American weather, now that the US soyabean harvest was virtually complete. Southern Brazil was forecast to be mostly dry this week, which will benefit fieldwork and planting as that area has been too wet, according to private US forecaster Meteorlogix.
However, northern Brazil and Argentina were on the dry side and in need of rain, it added. The soya products followed the fall and rise in soyabeans.
CBOT soyameal closed 40 cents higher to $1 lower, with December up 40 at $174.30. Soyaoil was 0.15 to 0.20 higher, with December up 0.15 at 22.96 cents per lb.
Soyaoil was supported by strong commercial buying, a trend for the past week or so. "But curiously, ADM, Dreyfus and Cargill all sold a couple hundred contracts late," said one CBOT soyaoil pit broker referring to late commercial sales.
The rebound in soyameal was contained amid worries about global feed demand due to the spread of bird flu. Commercials were net buyers of soyaoil.
Funds sold about 500 to 1,000 soyaoil and soyameal contracts. Malaysian palm oil futures closed weak overnight as dealers squared positions before November 1-10 export data, which may show a decline in shipments, traders said.