CHICAGO, ILLINOIS, US — Worries about dry weather in Argentina attracted speculative buyers to soybean and corn futures, causing prices to reach 6-1/2 highs on Jan. 6, Reuters reported.

Chicago Board of Trade March soybeans were 14½¢ higher at about $13.61½ per bushel after earlier hitting $13.78¼ on a continuous chart of the most-active contract since June 2014.

CBOT March corn added 3¼¢ to $4.95 per bushel after reaching $5.02¾ in mid-session trading, the highest benchmark corn price since May 2014.

March wheat dropped 6½¢ to $6.47½ per bushel.

Along with dry weather in Argentina, labor issues are causing supply concerns, Reuters said.

The CME Group, parent of the CBOT, said it would raise the margins to trade its soybean, corn and wheat futures after the close on Jan. 6.

“We have shaken some shorts out of the market with the CME increasing their (margins) ... If we continue to see a rally in this market, margins could potentially go up again,” Terry Reilly, senior analyst with Futures International, told Reuters.