Stem moisture and dew moisture are two different aspects of moisture content in hay, each affecting the haymaking process and the use of inoculants and preservatives in distinct ways.
Stem Moisture:
- Definition: Stem moisture refers to the water content within the stem of the hay. It is intrinsic to the plant itself, influenced by internal plant water and the hay’s overall moisture content during the growth and pre-harvest phases.
- Implications: High stem moisture can lead to challenges during drying because the moisture from the inner parts of the stem takes longer to evaporate compared to surface moisture. If stem moisture is too high at the time of baling, it can increase the risk of microbial growth and spoilage, even if the external parts of the hay appear dry.
- Interaction with Inoculants and Preservatives: Managing stem moisture is crucial when using hay preservatives. Preservatives, such as propionic acid, are often applied to hay that is slightly too moist to prevent microbial growth. If the stem moisture is not accurately accounted for, the hay may still spoil despite the application of preservatives because the internal moisture creates an environment conducive to mold and bacteria growth.
Dew Moisture:
- Definition: Dew moisture refers to the external moisture that condenses on the hay, typically during cooler nights or early mornings. It is not inherent to the hay but is instead a result of environmental conditions.
- Implications: Dew moisture can be beneficial as it can help reduce dust during baling and provide a slight amount of moisture that might help in the baling process. However, if the dew is excessive or the hay is baled while too damp externally, it can also lead to spoilage.
- Interaction with Inoculants and Preservatives: For silage, where inoculants are used to foster beneficial fermentation, dew moisture needs to be minimal at the time of ensiling to ensure that the inoculants can effectively promote the desired fermentation processes without competition from spoilage organisms. Inoculants rely on controlling the microbial environment, which can be complicated by excessive external moisture.
Balancing Moisture Content: Both types of moisture must be carefully managed to ensure the quality and safety of the forage. Farmers need to use tools like moisture meters to measure the hay’s moisture content accurately before applying any treatments. Understanding the different types of moisture helps in deciding whether to use an inoculant for silage or a preservative for hay, depending on the specific moisture-related risks present.