(Updates with analyst quote, prices, details)
By Mark Weinraub
WASHINGTON, May 10 (Reuters) - U.S. soybean ending stocks were seen rising to an 11-year high in the 2017/18 crop year following another bumper harvest, the U.S. Agriculture Department said on Wednesday.
Corn stocks were seen declining slightly but remaining plentiful. Wheat stocks were seen falling due to production dropping to its lowest level in 11 years.
The new-crop stock outlooks, the first issued for the 2017/18 marketing year, all came in below market expectations.
"USDA obviously is saying the demand profile is going to be strong again (for soybeans), said Jim Gerlach, president of A/C Trading in Fowler, Indiana. "Despite record crops in the U.S. and record crops in South America and record plantings in the U.S., we're not really growing surplus."
Soybean futures jumped to their highest levels since March 24 before quickly retreating to pre-report levels but remaining in positive territory. Corn futures firmed slightly while wheat turned higher.
USDA pegged 2017/18 soybean ending stocks at 480 million bushels. It also trimmed its soybean stocks outlook for the 2016/17 crop year by 10 million bushels to 435 million bushels. If realized, 2017/18 soy stocks would be the biggest since 2006/07 and the third-biggest ever.
U.S. soybean production was seen falling to 4.255 billion bushels in 2017/18 from 4.307 billion in 2016/17. Both exports and domestic usage were seen rising in the upcoming marketing year.
For corn, 2017/18 ending stocks were pegged at 2.110 billion bushels. The 2016/17 ending stocks projection was lowered to 2.295 billion bushels from 2.320 billion bushels.
Wheat ending stocks for 2017/18 were seen at 914 million bushels, down from 1.159 billion bushels in 2016/17.
Analysts had been expecting new-crop corn stocks of 2.122 billion bushels and new-crop soybean stocks of 563 million bushels, according to the average of estimates in a Reuters poll. New-crop wheat stocks had been expected to come in at 934 million bushels.
The USDA pegged the 2017/18 wheat harvest at 1.820 billion bushels, down from 2.310 billion bushels a year earlier. That would mark the smallest U.S. wheat harvest since the 2006/07 marketing year, when farmers produced 1.808 billion bushels.
Production of hard red winter wheat, the largest wheat crop, was seen falling to 737 million bushels from 1.082 billion bushels a year ago. Analysts had been expecting total wheat production of 1.859 billion bushels.
Reporting by Mark Weinraub; Additional reporting by Tom Polansek in Chicago; Editing by Paul Simao