One question that often comes up in any silage production discussion is whether or not to use a silage inoculant. There are 2 main types of inoculants; homofermenters and heterofermenters. Homofermenters contain Lactobacillus bacteria that produce lactic acid and heterofermenters contain Lactobacillus buchneri that produce lactic and acetic acid. The lactic acid promoting inoculants are used to increase silage quality by driving the silage pH down quickly and reducing DM loss during the fermentation process. Dry matter loss during fermentation is higher with the buchneri type inoculants but feed out losses can be reduced. The buchneri inoculants are used to increase the aerobic stability of silage during feed out. The acetic acid produced prevents yeast growth. Bill Weiss, OSU dairy nutritionist located at the OARDC in Wooster says that his standard recommendation regarding inoculant choice is that if you have historically had problems with moldy silage during feed out or if the TMR ration gets hot in the bunk, then use the buchneri type. If neither of these is an issue, then use the lactic acid promoting type of inoculant. Regardless of which inoculant type is used, the key is to purchase high quality inoculants and to apply them correctly.
After DM content, the next critical step is the rapid removal of air by packing. As layers of forage are added to the silo or pile, they need to be driven over multiple times by heavy machinery. The goal is to achieve a silage density of 15 lbs. of DM/ft3 or higher. The density is directly correlated with oxygen exclusion within the silage pack and generally high silage density results in lower DM losses. The guideline for packing is that 800 pounds of packing weight is needed for each ton of silage delivered to the silo or pack. For example, if the harvest rate is 50 tons/hr. then the packing weight needed is 50 x 800 = 40,000 lbs. or 20 tons. In addition to the packing weight, the thickness of the layer packed should be monitored. The optimum condition is to pack layers of 6 inches or less. Another piece of advice from Bill Weiss regarding packing is: If you think you have packed enough; pack some more.
The final important step is covering the bunker or silage pile. This should be done as soon as the bunker is filled and the final packing had been done. Covering prevents oxygen, weather and animals from getting into the silage pack. Covering reduces DM and spoilage losses. The recommendation is to cover with plastic of 6 to 8 mil thickness and weigh that plastic down, sealing the edges as well. University research trials have demonstrated that the oxygen barrier 2-step products have reduced losses more than covering with the 6 to 8 mil plastic.
Source: Rory Lewandowski, Extension Educator Wayne County