The Greenfudge.org site has an interesting list of various commonly trashed items and how long they take to biodegrade.  Were you aware that it takes two to five weeks for orange peels to biodegrade?  That glass jar you tossed? That takes a million years.  That itchy wool sweater from Aunt Erma?  Count on it hanging around for one to five years.  Of course, this list assumes the trash ends up in conditions where biodegradation is possible.  Unfortunately, once the trash ends up in a landfill biodegradation slows almost to a halt because of the tight packing of trash.

Typically in landfills, there’s not much dirt, very little oxygen, and few if any microorganisms,” says green consumer advocate and author Debra Lynn Dadd. She cites a landfill study conducted by University of Arizona researchers that uncovered still-recognizable 25-year-old hot dogs, corncobs and grapes in landfills, as well as 50-year-old newspapers that were still readable.

So make sure you try and recycle, reuse, or compost as much of your household waste to reduce the likelihood that your disposed items end up mummified in a landfill.