I have to add one disclaimer to this notice:
The good folks at World Wide Hippies added a series of photos to the article (I didn't supply them).
One photo shows 2 chemtrails. One is long and one is short. There is a caption pointing to the short trail that says "contrail".
I just want to be clear that both trails in the photo are indeed chemtrails.
Contrails are extremely rare and only (very rarely) occur at altitudes too high to be seen from the ground. If you're on the ground and you see a trail coming out of a jet, it's a chemtrail.
The only exception to this rule would be at air shows where they intentionally create smoke trails to help you follow the action.
Please see this article for details about the day that all persistent chemtrails turned to non-persistent contrails:
http://urlbam.com/ha/M003p