Silage: Why Didn't the Inoculant Work?

Many nutritionists and labs will use testing to find out why didn't an inoculant work. An good inoculant is an investment and can create problems if it doesn't get used correctly.

Even the best inoculant won’t help if air gets in. Ensiling is an anaerobic process, so be sure to:

• Pack silage tightly to eliminate air pockets

• Seal the bunker or silo as quickly and securely as possible

Silage inoculants work best when forage is ensiled at the correct moisture content:

• Haylage: 30–40% dry matter

• Corn silage: 30–35% dry matter

Too wet and you risk seepage and clostridial fermentation; too dry and compaction becomes a problem, reducing anaerobic conditions.

Another reason would be the ash or dirt content. Bacteria thrive on sugars and any dirt content will inhibit that access. Some beneficial ash from plants provide calcium, potassium, or/and magnesium, but detrimental ash from soil can contaminate the feed, cut nutritional value and reduce digestibility. The best ash content is under 10%

Apply the inoculant immediately after chopping. Delays between chopping and ensiling can reduce the inoculant’s effectiveness, especially if undesirable microbes have time to establish themselves. Bacterial inoculants start working the moment they are applied.

The inoculant was not stored properly. Bacteria in water soluble inoculants are living organisms and are activated by moisture. Once activated, they have enough food to live for about 48 hours. Multi-Sile II inoculant has a green dye in it. If the white powder has turned green, then the bacteria have been activated and are dead. The best practice is to keep inoculant in the fridge or freezer between seasons. Definitely don't leave an opened package in the cab of equipment during hot weather.

Another issue is human error, either by not mixing it correctly or not applying enough. The calculations for the correct dose will be different with every method of applying, either while chopping, bagging, baling or other storage options. Be sure to follow the rate on the package instructions. As long as the correct grams per ton are applied, it will not matter how much water you add. This is where calibration of tonnage, speed and pump rate will need to be calculated. Make sure to clean the hoses, nozzles and applicators so they won't clog up.