Harvesting Reminders for Small Grains

As we move into spring, many farmers will begin harvesting winter small grains. Commonly planted small grains in Pennsylvania include rye, triticale, oats, and wheat. While some farmers primarily use small grains to extend forage feed inventories, they are additionally beneficial to soil environments.

Small grains are harvested based on maturity, which often leads to a wet forage at the time of harvesting. While small grains must be harvested at an early stage of growth to ensure good feed quality, excessive moisture can pose a risk when ensiling. Small grains harvested during the flag leaf stage will likely have a moisture exceeding 70%. In this case, cutting the crop at the flag leaf stage to maintain quality and wilting the crop below 70% moisture prior to chopping will help avoid ensiling concerns with wet forages. As small grains mature, protein and energy will decline as grain fill is prioritized.

In Pennsylvania, spring rainfall is highly unpredictable and can prevent farmers from cutting at the flag leaf stage. However, planning for this can help avoid frustrations with reduced crop quality. Forages that must be harvested late due to weather conditions will have reduced quality as a milking cow feed but can be used to feed heifers and dry cows. When feeding small grains to close-up dry cows or heifers, be aware of potential issues with potassium levels. It is important to make sure your nutritionist regularly, as frequently as bi-weekly, samples small grains fed to dry cows and runs a wet chemistry package on minerals to balance a close-up ration correctly.

Harvested small grains are typically stored as either wrapped bales or in silos. For both systems, small grains stored with a high moisture content should be watched for both seepage and butyric acid concentrations. Penn State has recently collected field data from dairies feeding small grains stored either in vertical silos or in wrapped bales and analyzed the difference in management styles on particle size of the fed total mixed ration (TMR). Small grains chopped and stored in silos (Figure 1) compared to wrapped bales (Figure 2) had a more ideal particle size profile when incorporated in the TMR.

However, storing small grains in a silo is not an option on every farm. If small grains will be stored as wrapped bales, make sure to allow time during mixing for these to chop to a desirable length. Prior to feeding small grains, mixer wagon knives should be checked and either sharpened or replaced.

When harvesting small grains, keep your storage structure in mind. For small grains stored in bunks or piles, they should be covered quickly after packing and sealed using evenly spaced tires (Figure 3).

If small grains are going to be stored in an ag bag, keep in mind that all oxygen must be removed from the bag during packing to ensure an ideal fermentation and to maintain crop quality. Figure 4 shows two bags packed next to each other. The ag bag on the right was packed poorly and is noticeably lumpy. This packing allows for oxygen to be trapped within the bag. The left ag bag was packed appropriately to avoid oxygen being trapped within the bag. When using multiple bags, consideration for spacing between them should be given. Figure 4 also shows two ag bags with appropriate spacing between them. This spacing allows for machinery to retrieve feed from the bag without scraping, and potentially tearing the sides of the adjacent ag bag.

Figure 5 shows an image of two ag bags placed directly next to each other. In this situation, the unopened ag bag has been torn exposing the fermented feed to oxygen, likely leading to spoilage. Small grains stored in wrapped bales should be wrapped with a minimum of 7 to 8 layers of sun-resistant wrapping and repaired using ultraviolet light-protected plastic tape if torn​ (Purdue University).

Summary

Small grains are commonly used on Pennsylvania dairy farms and make an excellent milking cow feed when managed appropriately. Small grains can be used to extend forage inventories and provide a consistent feed on farms. However, when chopped late, small grains have reduced overall feed quality and might not support target milk production. While harvest timing will drive crop quality, improper storage can impact quality at feed out.

References

Johnson, K. 2020. Baleage Practices For Success. Purdue University Extension.

Ishler, V., Jones, C., Heinrichs, J., Roth, G. 2017. From Harvest to Feed: Understanding Silage Management. Penn State Extension.