Part of the problem is that geocaching recognizes "letterbox hybrids" as a cache type. Under caching's rules, it's a letterbox hybrid if it has a stamp. Neither text clues, nor a seperate listing on a letterbox site is required, although most hybrids are cross listed.

That means that some geocachers (especially new ones) believe that they are familiar with letterboxing based on what they have seen on that site as a hybrid. They may not be familar with "real" letterboxing, as seperate from geocaching. They would see a letterbox and assume that it's just another type of cache. Contrast that with letterboxing, where most of us know about caching, either through caching's publicity, or by encounters with the more numerous crowd over there.

The solution is proper labeling and communication. I would use the phrases "Do Not Trade - Leave in Box" on the back of the stamp, that's shorter and to the point. The same phrases on the baggie holding the stamp would be good too. I've left disposable cameras in my geocache (for self-potraits) with that labeling and they've stayed where they belong for three years and forty visitors.

When I find two close by (and I've chosen more than a few hikes for the chance to find some of each at the same time), I make sure to mention the letterbox in the cache log, with a reminder to treat the letterbox as they want their cache to be treated. Cachers are good people too, and that and good labeling are usually sufficent. Also, let each owner the other is nearby. In the case of newer letterboxers, point out any (lack of) labeling issues that might cause a problem.

In my most recent encounter with one of each side by side, I got a gift card (with a decent amount of value still on it) for Applebees out of the letterbox. The cache was a micro, so I didn't have to trade for it.

Thanks for all the information and tips everyone.  I appreciate it. 

I have seen trinkets in LBs and assumed that the placer added these in case a geocacher discovered the box and wanted to take a prize. Better to take the plastic bracelet than to take the stamp... I think this is a good idea just as insurance, if there is room in the box.

Well, my Ferns Too box had a plastic bracelet in it when I pulled it yesterday. I know *I* didn't put it there! There are a few caches in that park, so it might have been a geocacher who left it there.

Whoever it was, my son was thrilled with it, because it was green, and he's into some cartoon character that's green at the moment.

DebBee