NAPERVILLE, Illinois, May 27 (Reuters) - Speculators earlier this month were heavily dumping short positions in Chicago corn as wet weather held back U.S. planting, but the corn sowing pace returned to near-normal levels last week and funds reverted to selling.

However, shrinking Russian wheat crop estimates and troubles with Brazil’s soybean harvest kept speculators chipping away at bearish bets in those crops.

In the week ended May 21, money managers expanded their net short position in CBOT corn by about 50,000 contracts to 121,162 futures and options contracts. Nearly 80% of that move came from the reentry of gross shorts, the most for any week in almost a year.

Money managers in the same week reduced their net short in CBOT soybean futures and options to 26,426 contracts from 42,665 a week earlier, establishing their least bearish view since early January.

They also trimmed their net short in CBOT wheat futures and options to 24,593 contracts, the smallest since October 2022, versus a net short of 28,251 a week earlier.

During the week ended May 21, most-active CBOT corn futures slid 2% but soybeans were up 1.8% and wheat jumped 3.7%. Soymeal was down fractionally though soybean oil surged 5.6%.

Despite the easing in futures, money managers were net buyers of CBOT soybean meal futures and options for a seventh straight week in the week ended May 21. Their net long rose to 100,944 contracts, the largest since December, from 99,210 in the prior week.

Money managers through May 21 slashed their net short in CBOT soybean oil futures and options to a six-week low of 46,521 contracts, down more than 15,000 on the week.

Across CBOT corn, wheat, soybeans and products, and including Kansas City and Minneapolis wheat, the combined managed money net short is around 130,000 futures and options contracts, a little smaller than a year ago but relatively similar in context.

The biggest difference is in wheat, as money managers’ CBOT net short was about 120,000 contracts a year ago versus around 25,000 now. Their net short in K.C. wheat of about 17,000 contracts compares with the year-ago net long of 17,000.

Between Wednesday and Friday, moves in most-active CBOT futures were as follows: corn up 1.5%, soybeans up 1%, wheat unchanged, soymeal up 3.8% and soyoil down 1.9%. Soybeans made near-five-month highs during the period and wheat notched its highest price since July.

U.S. markets were closed on Monday for the Memorial Day holiday, but traders will be looking for the U.S. Department of Agriculture’s weekly progress report after Tuesday’s close to ensure corn and soybean planting is still on track after widespread wet weather in western areas last week. Karen Braun is a market analyst for Reuters. Views expressed above are her own.

(Editing by Rod Nickel)