Our local friends groups for dog owners: FIDOS (Friends Interested in Dogs on Open Space http://fidos.org/) instituted a program a couple of years ago, encouraging its members to take an extra poop bag on the Boulder trails. They asked everyone to pick up, not only their own dog's poop, but an extra one as well, in an effort to greatly reduce the dog poop on Open Space trails.
A Boulder County Open Space and Mountain Parks representative questioned the program's positive impact because it didn't change the behavior of the original culprits.
What's your opinion of the the FIDOS program?