Below is a summary of common silage problems, their likely causes and recommended actions.

PROBLEM: High pH

Probable Cause:

• Slow fermentation
• Yeast growth
• Bacillus growth

Management issue:

• If silage is not heating, feedout rate needs to be increased and/or a TMR treatment should be used
• If silage is butyric, feedout rate must be carefully controlled
• Performance is likely to be compromised due to lost energy in silage

Recommended action:

• Review all silage management practices, including harvest timing, chop length, speed of fill and pack rate
• Use a forage-specific bacterial inoculant

PROBLEM: Silage heating

Probable Cause:

• Yeast growth
• Bacillus growth
• Acetobacter growth

Management Issue:

• Feedout rate needs to be increased and/or a TMR treatment should be used

Recommended Actions:

• Review all silage management practices, including harvest timing, chop length, speed of fill and pack rate
• Use a forage-specific bacterial inoculant

PROBLEM: Moldy silage

Probable Cause:

• Mold contamination from the field
• Molds allowed to grow due to presence of air (oxygen) in silage structure

Management Issue:

• Large diseased areas in the field at harvest
• Delays during filling (bands of mold, fill lines)
• Poor sealing (mold at top or on sides)
• Slow feedout (mold across silage face)

Recommended Actions:

• Discard moldy silage
• Review fill rate and packing
• Use a forage-specific bacterial inoculant to inhibit spoilage

PROBLEM: Extremely low pH

Probable Cause:

• “Wild” lactobacilli naturally present in the silage resulting in slow initial fermentation

Management Issue:

• Carefully feed silage to avoid health problems in animals

Recommended Action:

• Review fill rate and packing
• Use a forage inoculant with a good homolactic LAB

PROBLEM: High ammonia

Probable Cause:

• Some lactic bacteria (Enterococcus, Streptococcus faecium) break down protein and can cause higher ammonia levels in otherwise well-preserved silage
• Can also result from clostridial silage or from enterobacteria
• Over-application of fertilizers (signs include very high crude protein)

Management Issue:

• Carefully feed silage
• If silage is butyric, limit inclusion in the ration
• If silage is not butyric, watch the level of nonprotein nitrogen (NPN) in the ration

Recommended Actions:

• Properly apply fertilizers
• Avoid soil inclusion
• Harvest drier forage
• Use a forage inoculant with a good homolactic LAB