Growing Beef Newsletter
October 2025, Volume 16, Issue 4
Start thinking about corn silage inventory now. Future you will thank you!
Dr. Gail Carpenter, ISU state dairy specialist
As corn silage harvest is wrapping up across much of the Midwest, it is time to think ahead to next fall. A common recommendation is to make sure that your corn silage will last you until next Christmas. The silage you put up this year will be the foundation of your feeding program for months to come. Taking the time to plan, measure, and monitor your inventory now can save you stress later and ensure your cows are getting consistent, high-quality feed.
Running short on corn silage can quickly turn into a costly challenge. On the other hand, if you have more silage than you anticipated, high corn silage diets can be a cost-effective way to provide both energy and high-quality forage. Planning ahead gives you options, whether that means stretching a tight supply or taking advantage of an abundant one. Working closely with your nutritionist is the best way to keep your plan on track.
Action items
A lot of value can be gained or lost depending on how silage is handled during and after harvest. Here are a few areas to focus on:
- Shrink at harvest and storage. Packing, covering with oxygen barriers, and keeping piles well-maintained are critical to reducing spoilage.
- Shrink at feedout. Daily management matters. Pay attention to how silage is removed and delivered to minimize waste.
- Dry matter (DM) monitoring. Silage DM will vary through the bunk. Regular DM checks help ensure you are feeding the amount of corn silage you think you are.
- Inventory estimates. Know how much silage you have and calculate how long it will last under current feeding rates.
Even small losses add up. By tracking shrink and DM, you will be in a stronger position to make ration adjustments before inventory becomes a problem. A simple starting point for many people when it comes to corn silage inventory management is to start making a routine of measuring corn silage DM. Be sure to use this information to make ration adjustments as needed. If you are using a feed management software, this is easy to update. If not, reach out to your nutritionist or extension specialist to help find a simple method that works for your system, such as a spreadsheet tool or an easy reference table.
Tools for tracking inventory
One of the simplest and most effective tools is routine DM testing. For many farms, checking once a week is a good starting point. These numbers should connect directly to your feeding program - whether that’s through ration software, a spreadsheet, or a simple table you update by hand. Your nutritionist or extension specialist can help set up a system that works for your farm.
When it comes to estimating inventory, three numbers are essential: pile or structure dimensions, average DM or moisture content, and density. Density can be measured in a few ways. Core samples are one option, though they require multiple samples, can be time-consuming, and sometimes pose safety risks. Another approach is the "feed-out method." Mark a section of the pile, feed from it for several days, record the weight and DM of silage removed, and calculate density by dividing weight by volume. If you use this method, always keep a smooth silage face to maintain safety and accuracy.
For bagged silage, the University of Wisconsin Extension offers a helpful online resource: Silage Bag Capacity Calculator. For piles, your nutritionist might have their own spreadsheet that they use. Alternatively, University of Wisconsin Extension also has this tool available: Silage Pile Capacity Calculator.
The bottom line
Corn silage is one of the most valuable feeds on the farm, so manage it well to maximize this investment. A little effort spent on planning now can go a long way toward ensuring a smooth feeding season in 2026.
This monthly newsletter is free and provides timely information on topics that matter most to Iowa beef producers. You’re welcome to use information and articles from the newsletter - simply credit Iowa Beef Center.
