CHICAGO: US soyabean and corn futures climbed to fresh 6-1/2 year highs on Wednesday, with corn at times rising above the $5 threshold, as worries about dry weather hurting Argentine crops attracted speculative buyers, analysts said.

Wheat futures fell on a lack of fresh supportive news and an upturn in the dollar, which tends to make US grains less competitive globally.

As of 1:13 p.m. CST (1913 GMT), Chicago Board of Trade March soyabeans were up 15 cents at $13.62 per bushel after earlier rising to $13.78-1/4, the highest price on a continuous chart of the most-active contract since June 2014.

CBOT March corn was up 3 cents at $4.94-3/4 a bushel after reaching $5.02-3/4, the highest benchmark corn price since May 2014.

March wheat was down 6-1/2 cents at $6.47-1/2 a bushel, but stayed inside of Tuesday’s trading range.

Dry weather continues to threaten soya and corn yield prospects in Argentina, and labor issues in the South American country have added to concerns about supplies.

“A water deficit persists mainly in Argentina, leading to fears of a downward revision of corn production,” consultancy Agritel said.

The union representing Argentine port-side grain inspectors was to meet on Wednesday with agro-export companies to try to clinch a wage deal that would end a strike that started on Dec. 9, a union representative said.

Underscoring recent volatility in the grain markets, the CME Group, parent of the CBOT, said it would raise the margins to trade its soyabean, corn and wheat futures after Wednesday’s close.