Unidentified Growth in Forest Preserve Mystery Solved

It was yet another beautiful day in the mid-forties in Chicago the 8th of January, 2012. We came across an odd growth when we were walking in a forest preserve nearby. I have never seen anything like it. So I put several pictures together in this collage.

If anyone has any idea what this could be let me know. It was a yellowy-sienna with a burnt umber linear mark in each nodule. Each individual one was shaped like a tooth with the depth of it being below the surface; coned there in a cluster. It was fibrous inside and the fibers were much more dense than any mushroom I've ever seen. At first I thought maybe it was an orange. But as we looked at others we found along the trail it was clear that these were not rotting oranges. I've never seen anything like it. So there's that.

And here's this.

Thank you!!! It is a Maclura Pomifera or an Osage Orange.

Here is a cool link.