* Wheat, soybeans at 2013 peak (Updates with closing prices)
CHICAGO, April 26 (Reuters) - Chicago corn futures climbed on Monday to their highest since June 2013 as concerns about South American supplies buoyed the market.
Strength in corn pulled wheat and soybeans to eight-year highs.
Chicago Board of Trade most-active July corn ended limit up at $6.57-1/2 per bushel.
July soybeans gained 23-1/4 cents to $15.39-1/4 per bushel after reaching $15.44-3/4 per bushel, their highest since June 2013. Wheat added 27-1/4 cents to $7.39-1/2 per bushel after reaching $7.46 per bushel, its highest since February 2013.
Dryness in Brazil threatens developing second-crop corn as late planting has left the crop vulnerable to drought damage.