This isn't a tree, is it? What example of tree abuse can this possibly represent?

Well, this is what happens to oak seedlings along the sides of Highway 113 between Woodland and Davis (in this case on the southbound side, between Willow Slough and County Road 29) when the Caltrans mowers come along.

That's the remains of the flagged stake they mowed down. Thanks for your diligence and care, Caltrans!