Corn is the input to US animal feed and ethanol, so its price connects grain, livestock and energy markets. Listed months are March, May, July, September and December, with December the new-crop contract that prices the harvest still in the ground.
The old-crop to new-crop spread — July against December — is the classic agricultural intramarket-spread, expressing how tight supplies are before the harvest arrives. Weather markets in June and July can move the front contract 5% in a session on a forecast change.
Daily price limits and expanded-limits apply, and lock-limit days do happen on major wasde surprises.
Example: corn at 445'0 is $22,250 a contract. A 25-cent limit move is $1,250. A farmer with 250,000 bushels of production hedges with 50 contracts.
Related: bushel, wheat-futures, soybean-futures, wasde, cattle-crush-spread