Is That Corn Crop Worth More as Silage or Grain?

Aaron Berger, Nebraska Extension Beef EducatorGalen Erickson, Nebraska Extension Beef Feedlot Specialist

Corn plant
There are three points in time where corn silage is often priced: standing in the field, packed in the silo, and delivered in the bunk. Photo credit Troy Walz.

Ongoing dry and drought conditions in many parts of the state are supporting hay and forage prices as we look towards this fall. Perennial dryland hay production in many parts of Nebraska has been less than average and annual forages planted for hay in the western third of the state look to be significantly below the long term average in terms of production.  Forage production on rangeland and pasture in southwest Nebraska as well as the Panhandle are in many situations significantly less than average.  This diminished production is going to result in less fall and winter grazing.   

Nationally there are sufficient stocks of corn and the current crop in much of the Corn Belt is estimated to be adequate to support December corn futures trading either side of $3.50 per bushel.  With the basis differences in Nebraska, a statewide average price is in the area of $3.00 per bushel of corn.  With harvested forage supplies being tight in much of Nebraska, harvesting corn for silage may be of interest this year, especially with fields that are drought stressed. Having the experience and facilities or area to put up silage is a very important consideration as well.

When evaluating whether to harvest a field for silage or grain, the issue of how to price and value the corn is often a point of uncertainty. Pricing corn silage can be a complex and highly variable process.  There are three points in time where corn silage is often priced: standing in the field, packed in the silo, and delivered in the bunk.

Corn for Corn Silage Standing in the Field

UNL research has shown that corn silage priced standing in the field before harvest should be valued at 7.65 x the price per bushel of corn where a ton of corn silage is harvested at 60-65% moisture. This multiplier value is consistent regardless of corn price.  Corn at $3.00 bu. x 7.65 = $22.95 per ton in the field.  This accounts for not having to combine or haul grain to market, but also should be harvest corn price, as we add storage costs to silage, yet corn price increases throughout the year due to storage, at least on average across many years of data.

Corn Silage Packed in the Silo

Harvest, hauling and packing expenses can vary.  The 2020 Nebraska Farm Custom Rates  survey showed a most common rate of $10 per ton. At $22.95 per ton plus $10 per ton for harvesting, hauling and packing equals $32.95 per ton in the silo.  When $2 per ton is added for storage expense the price per ton is $34.95.

Corn Silage Delivered in the Bunk

Corn silage due to the ensiling process will experience shrink and dry matter loss from 10-20% or more when silage is packed into the silo until it is removed to be fed.  With 10% dry matter shrink the value of silage delivered to the bunk would be $38.83 per ton. If the shrink loss is 20%, then the value of silage would be $43.69 per ton. Excellent information is available on the beef.unl.edu website illustrating the impact of covering, packing, and other management factors to decrease shrink.

Comparing corn silage under current market conditions to other feed resources can be helpful in evaluating whether to harvest a field for silage or as grain.  When comparing nutrients in feeds to one another, they should be compared on a price per pound on a dry matter basis consumed by the cattle.  This takes into account all waste loss and expense. The following examples are compared to one another on a price per pound of TDN (energy) on a dry matter basis delivered to the bunk.

  • Corn silage priced at $38.83 per ton that is 35% dry matter and has total digestible nutrient value (TDN) of 72% on a dry matter basis would cost $0.077 per pound of TDN.
  • Corn silage priced at $43.69 per ton that is 35% dry matter and has a TDN value of 72% on a dry matter basis would cost $0.086 per pound of TDN.
  • Wet distillers grains plus solubles at $55 per ton delivered that is 35% dry matter, has a TDN of 108% on a dry matter basis and shrinks 5% would cost $0.072 per pound of TDN.
  • Corn priced at $3.30 (average price for the year if $3.00 at harvest) per bushel and has a TDN value of 83% (note a TDN of 88-90 is in grain diets, not forage-based diets) on a dry matter basis would cost $0.084 per pound of TDN.
  • Grass hay priced at $90 per ton and has a TDN value of 53% on a dry matter basis would cost $0.095 on a dry matter basis.

There are several factors to consider when evaluating whether to harvest corn for grain or for silage. Both methods of harvest have advantages and disadvantages depending upon an operations goals and objectives. Tight forage supplies in many parts of Nebraska combined with current corn market conditions may heighten the attractiveness of harvesting corn for silage this year.  For more information on harvesting, storing and feeding corn silage, see the video presentations from the 2016 & 2018 Silage for Beef Cattle Conferences at the beef.unl.edu website.

The nutrient or fertilizer value of manure from cattle fed corn silage should also be taken into account in determining the value of corn silage.  In operations where the nutrient value from manure is utilized with cropping systems, this manure value should be credited back against the cost of the corn silage.  An article in the Progressive Forage Magazine titled “Silage pricing: Did you account for the manure?” highlighted this topic.

Drought Stressed Corn for Silage

Harvesting drought stressed corn as silage may be an option to salvage the crop and also produce needed forage. Producers considering harvesting drought stressed corn should also evaluate the impact of doing so to future crop production.  In a July 2017 issue of CropWatch, Bob Klein addresses this topic in an article Should You Hay or Cut Silage from Drought-Damaged Corn Fields?

The quality of drought stressed corn silage can vary but is usually 85-95% the energy value of regular corn silage.  A good measure to consider is doing a starch analysis. If you divide the starch % (DM basis) in corn silage by 0.70, that gives you an indication of the grain content in silage, which may be very important in drought-stressed or damaged silage. With drought stressed corn, caution should be used in harvesting if high nitrates are present.  Ensiling can reduce nitrates by 40-60%. Nitrates accumulate in the bottom of the stalk so raising the cutting height can also impact final nitrate concentration in silages, but also yield. For more information on feeding and pricing drought damaged corn silage, please see the article Options for Drought Damaged Corn Fields and the NebGuide The Use and Pricing of Drought Stressed Corn (G1865).  Both of these resources can be found at the beef.unl.edu website.

Interviews with the authors of BeefWatch newsletter articles become available throughout the month of publication and are accessible at https://go.unl.edu/podcast.