Nope, not a Corn, and definitely not a Copperhead. This is an Eastern Milk Snake(Lampropeltis triangulum triangulum), a member of the family that includes the King Snakes. The pattern on the head is different from a Corn, and these look nothing at all like a Copperhead, not even close.

I assume that is a captive snake (or an escaped captive). While the pattern and coloration might first suggest that it is a striped morph California Kingsnake (Lampropeltis getula), the head shape and pattern tells a different story. The head shape looks to me like that of a milksnake (Lampropeltis triangulum). Therefore I am pretty sure this is one of the captive hybrids between a Cal King and a Milksnake.

The only poisonous snakes in Wisconsin will have a rattle at the end of their tails. Also, those are very very rare here. Also, snakes are your friends. They will keep rodent populations under control. They are generally very shy and won't bother you unless messed with, or stepped on (do not try to pick up).

^ Not just feared...but absolute FACT! "The most severe declines in native species have occurred in the remote southernmost regions of Everglades National Park, where pythons have been established the longest. In a 2012 study, populations of raccoons had dropped 99.3 percent, opossums 98.9 percent, and bobcats 87.5 percent since 1997. Marsh rabbits, cottontail rabbits, and foxes effectively disappeared." "Bill Booth struggles to recall the last time he saw a raccoon, a fox or a rabbit on one of his frequent hunting excursions deep into the swamps of the Florida Everglades. An outdoorsman all his life, he knows as well as anyone how the native wildlife once abundant across the vast wilderness has been all but wiped out by an invasion of a deadly species he is trying his hardest to remove: the Burmese python." This invasive snake has ALREADY absolutely decimated the Florida ecosystem, consuming many native creatures there to extinction since just the 1980s!!!