We've seen numerous comments regarding low humidity relating to this
subject. Some of them suggest steps to control the humidity in the
house. I would like to point out that there are devices which mount
up inside a piano to control humidity very locally.  The one I have is
called a Dampp Chaser, since I live in the northwest, where humidity is
never too low for anything.  Check it out: http://www.pianolifesaver.com/ 

Lee Rothrock