Yes, the OED includes these two usage notes under corn n.1:
As a general term the word includes all the cereals, wheat, rye, barley, oats, maize, rice, etc., and, with qualification (as black corn, pulse corn), is extended to leguminous plants, as pease, beans, etc., cultivated for food. Locally, the word, when not otherwise qualified, is often understood to denote that kind of cereal which is the leading crop of the district; hence in the greater part of England ‘corn’ is = wheat n., in North Britain and Ireland = oats; in the U.S. the word, as short for Indian corn n., is restricted to maize.
Wheat, rye, barley, oats, etc. are in U.S. called collectively grain. Corn- in combinations, in American usage, must therefore be understood to mean maize, whereas in English usage it may mean any cereal; e.g. a cornfield in England is a field of any cereal that is grown in the country, in U.S. one of maize.