I got my new longbow this wednesday - a T-Hawk Diamond 'SS'. Yesterday, after a shooting session, I took a slightly moist ragcloth (and I litterally mean slightly moist, not wet), and gently cleaned the bow limbs.
And then... I noticed that the bamboo on the back started looking darker. The yew on the belly didn't change color at all. My first thought was: "Oh hell no, don't tell me that I ruined the wood now?" - so my question is... did I? I mean, the wood is covered with fiberglass laminations, so how is it even possible?
Note that I quickly grabbed a dry ragcloth to fix any possible damage, and then waxed the limbs afterwards.