Jonesella - NO! Not poisonous. They will bite if you pick them up wrong, and it hurts, but they have no venom. Racers eat rodents and insects and small birds. Good things to have around your landscape. Not so good around a chicken coop if you have tiny chicks, but you can use screens and keep them out until the chicks are bigger.

Appears to be an anerythristic corn snake. Quite common...who ever had the snake should know that and have further information for you.

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).

It is not a copperhead. Baby copperheads looks just like adult copperheads (and nothing like this). This is a harmless baby Racer (Coluber constrictor). It probably wandered in through some small opening somewhere. Sweep it up with a broom and release it outside and neither of you will be the worse for the experience.