Packing Bunkers and Piles to Maximize Forage Preservation

Forage is a valuable commodity stored on dairy farms. Bunker and pile silos have increased in use due to increasing herd size. Losses in feed value in bunker and pile silos are frequently higher than they should be because producers are not packing them sufficiently to exclude oxygen during the storage and feed out periods. The objective of this paper was to consider the recommendation of a minimum packing density of 240 kg dry matter/m3 compared to a minimum bulk density recommendation to keep porosity low. Our conclusions are that producers should try to achieve a minimum bulk density of 700 kg as fed/m3 while harvesting forage in the recommended range of 30-40% dry matter so as to limit porosity to a maximum of 0.4. This should result in lower losses of forage dry matter (DM) over a range of DM contents than when following the recommendation of a minimum packing density of 240 kg DM/m3.