is it the acid preservative?? if so, I think you pay for the weight, because that acid will sit in the bale for over 30 days forcing out any stem moisture, and creating a better bale for long term storage.
we try to bale at 15-18 % moisture, but in a pinch with weather moving in, we will bale up to 25% moisture.... only time the acid don't work is if we bale consistently over 34% moisture.