Yes it does make a sound. If you can't hear it, it still makes a sound. Not to mention in a forest something always hears it.
That's where things start to get tricky. Sound is vibrations that someone receives, but if no one is there to receive them it's just vibrations and nothing more.
Let's consider that nothing with a sense of hearing was nearby.
Sound consists of the vibrations in the air causing your eardrums to vibrate, no? Technically, no, there couldn't be (Assuming I'm right, which I never am. ;_
It depends. Do quantum physics include trees? If so, the tree is both fallen and standing at the same time, thus making both sound - and not making sound at the same time. In whch case the answer is clear.
If not however:
Sound is the mechanical vibrations transmitted by an elastic medium. In this case, yes of course sound is produced.
Sound is the subjective case of hearing something. In this case, no nothing experienced that sensation.
If think this scientifically it will make a sound which nobody will hear. If we think it philosophically it won't make a sound, because there is nobody who can hear it there.