Corn Silage

Background

• Importance of Corn Silage to Wisconsin
  • Largest acreage and production among U.S. States
  • Used extensively in forage base for state dairy herds
• Changing Wisconsin dairy production ‘climate’
• Wisconsin Corn Silage Consortium (Coors et al.)
  • Range for NDF and digestibility among commercial hybrids sold in Wisconsin is narrow.
  • Yield and quality differences among corn hybrids are repeatable.
  • Corn silage quality can be predicted using NIR

Corn Silage Compared to Other Forages

Advantages

• Palatable forage
• High dry matter yield and energy content
• Consistent quality
• Less labor and machinery (one harvest). Lower cost per ton of dry matter
• Manure management
• Flexibility, dual purpose

Disadvantages

• Few established markets
• Relatively low in protein
• High transportation costs
• Must be fed on or near farm
• Expensive storage facilities
• Limited production on erodible soils due to conservation requirements

What makes a good forage? (Carter et al., 1991)

• High yield

• High energy (high digestibility)

• High intake potential (low fiber)

• High protein

• Proper moisture at harvest for storage

• Ultimate test is animal performance

  • Milk2000 is our best predictor for performance (Schwab - Shaver equation)

Hybrid Selection

Criteria for Selecting Silage Hybrids

• Grain yield: allows flexibility (dual purpose)
• Whole plant silage yield
• Relative maturity: 5-10 days later than grain hybrids
• Standability: allows flexibility
• Pest resistance
• Silage quality

“Variation for silage yield and quality exists among commercial hybrids in Wisconsin.”

"Dual Purpose" Hybrids versus Silage Specific

Other silage Hybrids

• High sugar
• Waxy
• High-oil
• Leafy Corn
• Bmr Corn
• Tropical
• Sweet corn

Silage Quality

Bt versus Conventional hybrids 

Management Guidelines for Corn Silage

Silage yield and quality changes during corn growth and development

Planting date response

Plant density response

Row spacing response

Cutting height response

When to Harvest

Harvest timing depends upon storage structure

Environment drydown rate average = 0.5% per day

Kernel milkline: use as a guide

Predicting corn silage harvest date

• Planting date
• Hybrid Relative Maturity
• Silking date: add 42 to 47 days
• Once kernel milkline begins to move measure whole-plant moisture and use drydown rate = 0.5% per day
• Final check

Harvesting Stressed Corn

• Frosted corn
• Drought-stressed corn

Fermentation

Silage additives

Silage Preservation--The Role of Additives (A3544)

Storage structures

Further Reading

From Harvest to Feed: Understanding Silage Management Penn State University Circular (2003)