How do I get squirrels to eat corn?

I bought a squirrel feeder at the Wild Bird Shop and a dozen ears of corn, because we have squirrels in our backyard, always digging up the ground burying or looking for their nuts, and I wanted to give them something else to eat (and I thought it would be amusing to watch.) The feeder is hanging from our clothesline. But the squirrels are just ignoring the corn. I even put one of the dried ears of corn on the ground, and it gets completely ignored - the squirrels run right past it. No birds seem interested in the corn either, even crows that sit in the tree. Why is this? What can I do to get the squirrels to eat my corn?