Silage is an Option
• Drought-stressed corn that is unlikely to
resume growth should be ensiled.
• 85 to 100% of the normal net energy content.
• May contain more crude protein.
• May contain high nitrate concentrations,
especially in the lower third of the plant.
• Do not feed until at least 3 weeks after the
silo has been filled.
Corn Silage: Nitrate Caution
(NO3) in Dry
0.0 – 0.44%
Safe to feed.
0.44 – 0.88%
Limit to 50% of total dry ration for pregnant
0.88 – 1.50%
Limit to 25% of total dry ration.
Avoid feeding pregnant animals.
Toxic. Do not feed.
At high enough concentrations, nitrates are poisonous to cattle.
The ensiling process will decrease nitrates by 30 to 50%.
Corn Silage Harvesting
• Milk line is ½ to ¾ down the kernel.
• Leaves above the ear should be
• Dry matter content should be near
35%, slightly less for storage in
bunkers, trenches, or stacks.
• Silage should be chopped into
lengths of approximately 3/8 to 1/2
Corn Silage Storage
• Any structure that preserves the green and moist forage
in the absence of air and water.
Corn Silage Moisture:
Collect a representative sample of fresh plants.
Chop the plants in 1 to 2 inch pieces.
Weight a sample (about 3 to 4 oz or 100 g)
Spread the sample uniformly and thinly over a microwave safe dish and
place in oven.
Heat for 1 to 2 minutes and weigh. Heat for 30 seconds and reweigh.
Repeat until two weight recordings are similar. If the sample chars, use
the previous weight.
Calculate the percent moisture.
% moisture =
fresh wt – final wt.
Corn Silage Moisture: Grab Test
Squeeze a handful of green chop as tightly as
possible for 90 seconds to make a forage ball.
Condition of forage ball
Approx. Dry Matter
Holds shape and there is considerable free juice
Holds shape but very little free juice
25 to 30%
Falls apart slowly and there is no free juice
30 to 40%
Ball falls apart rapidly
Corn Silage: Production
• Planting Date
– April 1 to May 1 in western Kentucky
– April 15 to May 15 in eastern and central KY
– Soil temperatures should be above 50oF at a 2inch depth for 3 or 4 days
• Planting Depth
– 1 ½ - 2 inches (depending on moisture and
Corn Silage: Production
• Planting Population
– 24,000 to 30,000 seeds/acre
– increase of 2,000 seeds/acre over grain corn
• Row Width
– 30 inches
– Follow AGR-1: Lime and Fertilizer
Corn Silage vs. Grain Production
• Increase plant populations by about 2,000 seeds/A
compared to grain corn.
• Add more pounds of potash per acre compared to
grain corn (see AGR-1).
• Use a full- to late-season, high grain producing hybrid.
Silo Gases: Caution
• Lethal gases - greatest danger is between 12 to
72 hours after filling.
• Run the blower.
• Stay out of the silo for at least one week after
• Keep doors closed between silos and barns.
Any experience of the slightest throat irritation or
coughing requires immediate medical attention.
Nutrient Sampling for Feed Quality
• Collect a couple handfuls of each load of silage that
is being unloaded.
• Keep the samples out of sunlight.
• Mix the samples together.
• Keep refrigerated until sent off for analysis.
• AGR-79: Producing corn for grain and silage
• ID-139: A comprehensive guide to corn
• AGR-1: Lime and fertilizer recommendations
• AEU-41: Temporary silage storage
• ID-86: Using drought-stressed corn: harvesting,
storage, feeding, pricing
Corn Hybrid Types
– Normal corn hybrids used for grain and/or silage
– Slightly higher oil and protein content in the kernel
– 100% amylopectin (believed to be more digestible)
– Have more leaves above the ear than normal
– Lower lignin content than normal corn, making it
No-Till Silage Project
• Four hybrids
• Three Populations
• Two N Fertility
– Yield Goal
Hybrid effect on yield
Dry Matter 10
Silage Yield Ear:Stover
Note: Interactions between population, fertility and replication prevent statistical comparison of hybrids for silage yield.