The one BIGGIE about unrolling hay is if your calving anytime during the hay feeding time .....you are way less likely to lose a calf to trampling, because they want to get somewhere dry and thats usually right next to a hay ring. Someone told me just the other day about losing several calves from trampling around a hay ring. I've never had a calf trampled where the hay was unrolled. Losing just one will offset any hay you think you might be wasting.