November soybeans closed a penny lower at $5.73-1/2 per bushel and January was down 1-1/2 at $5.85.
Brokerage firm FC Stone said late Tuesday that it estimated the US soy crop at 3.064 billion bushels, higher than the USDA's October estimate for a 2.967 billion bushel crop. If realised, the 2005 harvest would be the second-largest US soy crop in history. The forecast reflects a yield of 43 bushels per acre.
Other estimates were expected this week, preceding USDA's November 10 supply and demand report.
Firm US cash soybean and soymeal markets helped underpin both. Soyoil was pressured by steady to weaker crude oil markets and some concerns about the use of soy-biodiesel.
Minnesota on Friday suspended for 10 days its law requiring that diesel fuel sold in the state contain 2 percent soy-based biodiesel due to quality problems with a batch of biodiesel.
"I don't think it's anything longer term but it's overhanging the market today," one CBOT cash-connected trader said.
Soymeal closed higher, gaining on soyoil as the oil/meal spread corrected, traders said.
December soymeal settled 40 cents higher at $173.90 per ton, with deferreds up 80 to down 40. December soyoil closed 0.18 cent per lb lower at 22.84 cents, with the back months 0.15 to 0.21 cent weaker.
The value of soyoil in relation to soymeal fell this week, with oil below 40 percent of the combined value of the soy products. Soyoil closed at 39.64 percent of the combined product values of the December contracts.
The oil/meal spread peaked in early October, reaching 42 percent when the energy markets rallied. Expectations for increased demand for soy-based biodiesel amid escalating crude oil prices prompted soyoil to gain on soymeal last month.
"With the energy markets coming off, it's a little bit less of a play from the spec standpoint," the CBOT trader said referring the recent sell-off in soyoil by funds.
Much of the adjustment in the spread came from outright trades as commission houses and commercials sold soyoil. Commodity funds were about even in soyoil and bought about 500 soymeal contracts.
Export business in soybeans remains routine and lagging a year ago pace despite steady Chinese interest in US soybeans, traders said. Overnight business featured Taiwan buying 57,000 tonnes of US soybeans.
Concerns remained about the future demand for soybeans and soymeal given the spread of the deadly bird flu virus in Asia and Europe.
There were heavy soy deliveries of 693 against the November contract on Wednesday. But they were met by likely commercial stopping with a Tenco customer taking 485 lots. Registrations with the CBOT were unchanged late Tuesday at 1,572 lots.
Harvest of the US soybean crop was basically done. But clear weather most of this week should help farmers trying to get in the last of their soybeans. Rain later this week in the eastern belt could stall harvest.
South American weather was generally favourable for planting soybeans. Scattered showers in the northern areas of Brazil and drier conditions in the south improved planting conditions, said Meteorlogix weather service. But there was some concern about dryness in Argentina, traders said.