Strictly speaking, you do not have to apply to engineering as a freshman at a lot of schools with engineering, but you may need to apply to declare the major once enrolled if you are not admitted as a freshman into the major.
For example, University of Washington was mentioned above in post #9. Yes, you can enter as an undeclared freshman and then major in engineering. However, all engineering majors require applying to declare with competitive admission, according to this list:
UW Advising - List of Majors .
