It's actually more than a property crime. The professor is an employee of a state institution. She is therefore an agent of the state, who in that capacity incited others to suppress the speech of those who planted the crosses in the first place. If that isn't state action in violation of the First Amendment, I don't know what is. How about a civil action against the professor, the university, and the State for this civil rights violation?
Incidentally, this "professor" probably supports Planned Parenthood counseling that is based on the premise that a fetus is not a human being while at the same time she believes that a visible statement that a fetus is a human being is worthy of suppression.