By Dwane Miller, Educator
With limited moisture in some parts of the state this summer, farmers are beginning to evaluate their corn crop and will make a determination of whether to chop the corn for silage or take the corn as grain. While this judgment may be more of an art than a science, there may be some factors to consider that may aid in your decision-making process.
One of the first things to evaluate is whether or not a field has pollinated. If the majority of the field has not pollinated, then we would recommend harvesting the field as silage. The “shake test” can be used to determine an estimate of pollination across the field. You can learn more about the ear shake method from Purdue’s Bob Nielsen.
To estimate the potential grain yield of the corn crop, you can conduct a simple evaluation. First, count the number of kernel rows on a representative ear. Then count the number of kernels per row. Next, determine the number of ears per acre. Now, multiply the kernel rows by kernels perrow and then by the ears per acre. Divide this number by 90,000 to get bushels per acre. Repeat this process at several areas in the field to get a representative sample of the crop.
This estimate is for average size kernels; the final yield will depend on conditions during grain fill. If drought stress continues through the grain-fill period, this may overestimate yields.
Once you have determined the best use for your corn crop, be sure to check with your crop insurance agent and your local FSA office before harvesting the crop.
Pricing immature corn silage can also be an issue. According to Grain Crops Specialist Greg Roth, values of drought-stunted corn will vary. In one recent scenario of prices, drought-stunted corn with few ears was worth about 91% of normal silage, while drought-stunted corn with no ears was worth only 66% of the value of normal corn silage. When pricing corn silage, be sure to consider harvesting and hauling costs as well as the moisture content of the silage. A Cornell University Extension fact sheet lists considerations when taking corn for silage, including some pricing considerations.
You can find more information on dealing with various weather-related problems in corn (drought, wind, hail, flooding), on the Penn State Extension Grains website.