Any cut timber allowed to see full light of day will get cranky on you really fast, if your pile is staying there for some time, try and give it some cover from the sun. Maybe put some shets of tin over it and give it a good overhang. Also if teh cut timber is to be something you want to get a good return from, strap the stack with ratchet tie-down straps and keep the tight over time.

Just a few things I have found which help to keep the timber from going cranky.