Lots of good advice has been given already. I find that smoking "similar blends" in a pipe will generally not result in unwanted ghosts! The real trick is to define "similar blends"! I suggest that you let your nose decide before you pack the tobacco in your pipe. I do separate my pipes into four categories:
1. Non-Aromatic blends containing no Latakia.
2. Mild Aromatic blends.
3. Specific Aromatic blend to specific dedicated pipes (as in Captain Bob's Blend).
4. Blends containing significant Latakia.
Keeping a clean, reamed and dry pipe will speed up the process of getting rid of the unwanted ghost flavor of most blends without having to take drastic measures. Most "ghosting" problems seem to emanate from over-smoked pipes. The more pipes you have, the better. Even if you only smoke one favorite blend. Pipes will sour if too saturated with tobacco juice. Rotate your pipes and give those pipes a rest!
By the way, Captain Bob's Blend should be smoked in a clean, dry, dedicated pipe as it will ghost the pipe for a while. It is a blend containg 1/16th Latakia (very light). But, it is the Aromatic that is reponsible for ghosting pipes and I much prefer dedicating pipes just for my Captain Bob's Blend. Those ten pipes have never smoked any other blend. And, the reward is significant. If you really like a blend, I always recommend dedicating pipes to it. You will not be sorry that you did.
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