With dry conditions still plaguing much of Nebraska, baling corn residue following harvest might be an optional roughage source if hay supply is getting tight. What value should be put on baling corn residue?

Figuring out the true value of cornstalk bales can be a bit tricky, but breaking down the costs can help it make sense. First, look at the value of nutrients removed from the field that will need to be replaced by fertilizer. Stalks this fall will contain between $3 to $5 worth of nitrogen, potassium, phosphorus and sulfur per ton.

Stalks also provide organic matter and help reduce erosion. We need to account for the loss of these benefits as well. Nebraska research shows that dryland corn yield declines about 2 bushels for each ton of residue removed. Irrigation costs increase similarly to maintain yields in fields when residue is removed, accounting for an additional $10 to $12 per ton.

Baling stalks is harder on equipment than putting up grass or alfalfa hay. This additional labor and equipment cost comes in about $20 to $25 per ton. Adding everything up, we accumulate $33 to $42 in cost per ton of residue removed.

With costs calculated, we have to figure out what a bale is worth. From a nutritional standpoint, cornstalk bales are typically even lower quality than straw. 

Even if being selective with what we harvest by only baling the two to three rows behind the combine, we can only count on about 5% crude protein and up to 45% total digestible nutrients. With these values, combining stalks with distillers grain in a diet may be the most efficient use.

To find the value, we need to compare a cornstalk or distillers grain diet with what it would be replacing. William Edwards, Iowa State emeritus ag economist, worked on this problem in the worksheet here: extension.iastate.edu/agdm/crops/pdf/a1-70.pdf.

For his example, the original diet consisted of 2.6 tons of hay and 0.3 ton of dry distillers grain. To add in 1 ton of cornstalks, the diet was adjusted by adding an additional 0.22 ton of distillers grain and replacing 1.16 tons of hay. With this example, we can use the other two feedstuff values to estimate a value of stalks.

If we put hay at $100 per ton and dry distillers grain at $160 per ton, the stalk value would be 1.16 x $100 (hay value) minus 0.22 x $160 (distillers grain value), which comes out to $80.08 per ton.

The stalk and cob in corn residue are unpalatable and will not be consumed unless the bale is ground. So, to improve feed value, grinding cornstalk bales is common. This cost needs to be taken into consideration and reduces the value to the end user by $10 to $15 per ton.

In the end, this drops our cornstalk value to $67.80 per ton. This value can serve as a breakeven point when deciding if buying corn residue bales or traditional hay rations will be more cost-effective.

The one factor that is hard to calculate is demand. When feedstuffs are limited, the natural market fluctuations are out of our control. This example can help with finding an approximate breakeven point between hay and cornstalk rations and guide decisions on what the most cost-effective route for feeding animals this winter is. To account for regional differences, change the values for dry distillers grain and hay to match local prices.

So, is cornstalk harvest worth it? While there are always additional variables and costs to consider, a quick comparison shows that this year with fertilizer prices down, and hay prices up, cornstalk bales may be a reasonable option to explore.

Beckman is a Nebraska Extension educator.

Source: UNL BeefWatch, which is solely responsible for the information provided and is wholly owned by the source. Informa Business Media and all its subsidiaries are not responsible for any of the content contained in this information asset.