Corn Silage Considerations for 2024 – Three Key Questions

BY Dairyland Seed Agronomy Team

2024 Silage

Now that wheat harvest is mostly complete, and the 3rd or 4th crop hay is being harvested, it is time for our dairy/cattle producers to prepare for an important harvest. Corn silage is the dominant forage fed on most dairy farms, often accounting for 70% or more of the forage portion of modern diets. With this high inclusion rate, producers need to grow, harvest, and store more tons of corn silage per animal than they did in past decades.

What makes corn silage harvest so important? The resulting product plays a significant role in the level of milk or beef production a farm can achieve, as well as the cost of the total ration fed to the animals...for an entire year! TIMING IS EVERYTHING! The value of this high energy crop depends on proper fermentation, which affects nutrient availability and preservability of the feed produced. The largest contributing factor to proper fermentation is harvesting the silage at the proper whole plant moisture content. The proper moisture content depends on the type of storage structure and has remained consistent for several decades. (See Table 1) Depending on weather conditions, the window to harvest corn silage at the proper moisture is very narrow compared to other crops. If you miss it by a few days, or jump the gun and harvest too early, it impacts a full year of production and profitability.

What makes 2024 different? We know 2024 has been a challenging growing season for most producers throughout the Midwest. This is especially true when compared to 2023. Although most of us were concerned about impending drought conditions, 2023 featured pleasant planting conditions and bountiful yields, along with a very digestible corn silage crop. Knowing that we are looking at a corn crop with a high degree of field variability this year, it is important for silage producers to consider these 3 key questions now.

What yield do I expect to achieve compared to an average year? This cannot be answered at 60 mph through a truck window...especially not this year! Please make sure that you or someone is walking your fields and getting a good estimate of the average tons per acre expected. Although there is opportunity to influence yield through kernel fill yet this season, most other yield factors are already determined. Once an estimate is achieved, look at your inventory and run some scenarios. Having a plan for best case/worse case scenarios can help you avoid surprises at harvest time. It also allows you to explore options, such as harvesting more acres than planned, purchasing corn silage acres from neighboring fields, or locking in forage stretching by-products for the year if they are available.
How will I achieve the proper whole plant moisture? A high degree of variability within fields makes this challenging! Most years we can select a representation of plants from a field, grind a sample, and get a decent idea of when we should start harvesting. This method will be less reliable in 2024 because of in field variability. If you have your own harvesting equipment, taking field length samples will be the best way to determine actual whole plant moisture content. For those utilizing custom harvesters, you will need to have effective communication and work together to ensure your goals are achieved.
How can I maximize consistent quality? Again, a high degree of in field variability makes this challenging. There will likely be high starch, low starch, and even no starch content silage coming from within any given field. Kernel processing and length of cut will need to be closely monitored. For those with drive over piles or bunkers, spreading loads as thinly as possible over the surface of the structure will help achieve greater consistency at feed out. For those with multiple upright silos or silage bags, consider segregating your silage by quality into different structures. This allows for choosing inclusion rates from each structure based on diet needs throughout the year. Whatever your storage situation is, it will be important to be vigilant with forage sampling at feed out to make necessary diet changes. The nutrient values of the silage can be expected to bounce around more than they normally would.

Table 1. Recommended moisture content (%) for corn stored in various types of storage structures.
Upright oxygen limiting silos	50-60
Upright concrete stave silos	62-67
Bag silos	60-70
Horizontal bunker silos	65-70
Roth et al., 1995