Hey guys I was shooting one of my maple self bows yesterday and it was warm and really humid. My bow seemed to be lacking power and when I checked the poundage it was at least five pounds lower than last time I checked. Have you guys noticed anything like this before or do I have a faulty scale?

White wood bows do tend to lose cast in hot humid weather, sinew backed bows can suffer from this also.

It's noticable but I don't think it has been much researched or documented.  Some of the books which describe the working properties of wood cite the moisture content, but not very specifically, neither do they compare properties at various moisture levels.  This is perhaps the single most important consideration when building and using all wood bows, imho.  

Also I think at the root of the contraversy over the years wrt to which species make the "best" bows.  Lessons from antiquity, where performance was judged across a variety of conditions, casts a much different picture than the neo-dogma, which laudes the utility of most any species without as much regard for this consideration.  Perhaps because, contrary to older times, given our modern lifestyles one can pretty much dictate and control the moisture content of one's bows without too much effort.

Unfortunately finishes and sealants are not very effective at combatting uptake of moisture.  Wood "breathes" regardless of what you do.  But some coatings are better than other, simple parafin wax for example can be very helpful.  I use it on top of several coats of polyurethane.  Modern catalyzed varnishes and epoxy finishes are also said to be more effective.

Lee, I agree that is typical of some whitewoods when left out in humid conditions for long periods. Hickory has a reputation for that. Then again I took a  white mulberry bow to Mojam in 2003 and that took on limp noodle like qualities pretty quickly. My bows stay in AC in the summer. Jawge

Thanks guys! Yeah pretty interesting stuff kinda frustrating too when you go to shoot past twenty yards and can't figure out why you're hitting 6" low

If your house is air conditioned and you keep your bows inside, humidity shouldn't be a factor. If no a/c store them in a hot box at lower temps(90 to 100deg) while not in use.

agree with DCM, have your moisture content down to where its supposed to be for your climate, i put several coats of true oil (3-5) then wax it periodically, n.h. summers get pretty humid but i have yet to notice any problems. good luck

Of the bows that I've tested under those conditions that didn't lose weight was a bamboo backed Ipe. But in cold conditions that type of wood seems to tighten up a bit. Having the right bow for the right day really helps. Hickory for those really dry days, and Osage for everything in between. ART