pink ribbon

The status of this ribbon rather mystifies me.   It's hanging in a tree at the side of the Rutgers carpark that's in front of my office - but I don't have a clue whether it's a hang-over from Breast Cancer Awareness month, or something to do with construction work, or some kind of tagging clue in a treasure hunt, or some mysterious symbol to do with some fraternity or sorority ritual (for this is Union Street, where a substantial number of these institutions maintain their houses).   There's another one a little further down the street, but that doesn't further the argument one way or another.   For that matter, the trees on Voorhees Mall all seem to have red ribbons tied round them - but is that simply a cheery demonstration of Rutgers red, or a show of strength in relation to AIDS awareness, or something else more obscure?   Enlightenment welcome.