Hi!  We've been using crib halt for years on our plywood panels that line our pipe corrals, and act as a windbreak.  The horses don't touch them.  We just paint the upper edges. Every now and then after about 6 months, they will dry up a little and our pony may sample a bite, but I just paint a little more and they stop chewing.  They have never harmed any of the animals or my skin, except it's impossible to scrub off, so I wear a real long sleeved old shirt.  We used to use creosote back in the 70's, the stuff they used to put on telephone poles, but it's illegal now in California.  I don't want them eating wood, I've hear conjecture, that it is possible  that splinters can cause intestinal problems, even contribute to the formation of enteroliths, I heard this from the local equine Hospital.   Maybe someone can think of something better, but if not, you can know we've done okay with the stuff.  Beth