Inoculant Mixing & Application Critical Steps in Silage-Making Process

By: Farm Journal Content Services, Previously posted on Drovers Online

It’s a three-step process with silage inoculants. First, decide where you need the help – up-front fermentation, improved aerobic stability at feed-out or both. Next, pick a research-proven and tested product. Lastly, be sure to manage the application. Professor and head of the Silage Fermentation Laboratory at Delaware University Dr. Limin Kung Jr. explains that details matter when it comes to choosing your inoculant, and especially in preparation and application.

Inoculants fall into one of three categories. Be sure to choose the one that fits your crop’s needs:

1. Inoculants designed to improve the initial fermentation process
   1. Microorganisms include Lactobacillus plantarum, Enterococcus faecium and variousPediococcus species.
   2. Mainly used on alfalfa and grass silage.
   3. Benefits
      1. Quickly lowers the pH level of the silage and helps inhibit undesirable fermentation of microorganisms like Clostridia and Enterobacteria.
      2. Helps create a more efficient fermentation that provides better dry matter energy recovery.
      3. Can reduce proteolysis (breakdown of proteins).
2. Inoculants designed to improve the aerobic stability of silages
   1. The primary organism in this category is Lactobacillus buchneri.
   2. Designed for use on high-moisture corn, snaplage, earlage and high-dry-matter silages.
   3. Benefit
      1. Improved aerobic stability reduces dry matter and energy losses from aerobic deterioration.
3. Combination
   1. Used to improve both the front-end fermentation and also to be a back-end stabilizer.
   2. Designed for use with corn silage because it tends to be drier at 35 to 40 percent dry matter and have problems with aerobic stability.
   3. Benefit
      1. Maximizes dry matter and energy recovery during the entire process.

Inoculant Mixing and Application Tips

“Preparation and application are so important with all inoculants, but especially inoculants that are being mixed with water,” says Kung. “Don’t use hot water to make a liquid inoculate mix, because the hot water will kill the bugs.”

Distribution of the inoculant within the harvested crop is critical. Producers should ensure applicators are calibrated correctly. Kung recommends checking the calibration several times throughout the day to make sure spray nozzles aren’t plugged and the application rate is correct based on the tonnage being brought in.

“Based on studies, if a grower is going into a bunker or pile, it is more efficient to put the inoculate on at the chopper in the field than trying to pour the inoculate on the top of a silage wagon and hope the inoculant gets mixed in when it’s pushed into the bunker or pile and packed,” he says.

If silage is being packed into a bag or tower silo, good distribution is still possible because the inoculant can be easily metered onto the forage at the blower. However, if the forage being chopped is several hours away from the tower silo or bag where it will be stored, then in that scenario, Kung recommends applying the inoculant at the chopper in the field.

“When you’re putting on a liquid inoculant, the mix is usually good for 24 to 48 hours, which is not typically a problem with big operators, but for smaller operators it can sit in the tank too long and it’ll start to go foul,” he says. “Producers also want to make sure the liquid in the application tank does not get above 95°F to 100°F because it will start to kill the bacteria. This usually occurs because the tanks are too close to the engine of the chopper.”

When storing an inoculate between cuttings, be sure to read and follow the manufacturer’s recommendations, Kung says.