There is no denying that weather conditions have created a challenge for some farmers trying to make hay this season. Dealing with heat waves, late spring cold snaps, lack of winter snow cover, drought, and excessive flooding has become the new normal in many parts of the country. Extension forage specialist Kim Cassida of Michigan State University provided advice as to how we should navigate weather extremes when it comes to making hay in a Field Crops Virtual Breakfast webinar.
Weather patterns are looking very different from those of years past. “Over the long term, the erratic weather has been having an effect on our forages because they cause stress on our plants, and stressed plants don’t yield well. Too much accumulated stress can kill them,” said Cassida. Weed invasion can also become a problem during these periods of time when forages are weakened, and farmers are unable to get into fields. However, there are some coping mechanisms that farmers can implement to try to mitigate these effects. Monitoring soil pH, fertility, and reducing field traffic are all ways to help with weather stressors.
Weather events have also made it increasingly difficult to get hay dry once it is cut. “What we’ve been seeing over recent years is everything coming at us seems like rapid fire,” stated the forage specialist. Making hay at the correct moisture will help put up good quality forage, so it is important to understand the stages of hay curing.
Phase one occurs when water is actively pumped out of the plant, driven by photosynthesis. Phases two and three are driven by evaporation — generally the leaves are dry, but the stems are not. The goal during the hay curing process is to get moisture levels to below 60%, ceasing respiration before the first night after cutting. At 60% moisture, the plant stops burning sugar inside its cells. Cassida recommended creating swathes that are 60% to 70% of the mower width, leaving at least 3 inches of stubble behind for regrowth purposes.
When it comes to baling, it is important to remember that hay continues to dry after it is baled and may heat up. Sweating is a microbial reaction that can cause heating in bales two to three weeks after baling. Although some heat is helpful and can drive off extra moisture, excess heat can cause protein damage or even combustion. Bale temperatures over 125°F and above 25% moisture will cause protein damage, while any bale temperatures over 150°F and 33% moisture run the risk of fire. Baleage, on the other hand, may be baled at 50% to 60% moisture. To avoid heating and potential combustion, consider stacking hay in a way that allows airflow to dissipate the heat.
Hay that has been rained on presents its own set of challenges. Although rain directly after cutting can have little impact, it is important to note that forage losses are correlated to the amount and timing of rainfall. Precipitation can cause loss of water-soluble carbs and minerals via leaching. It can also boost chances of leaf loss, mold, postharvest heating, and drops in digestibility. It is during this period of time that many farmers are asking each other, “Should I wait, or should I cut it?”
Cassida stated that advancing maturity may have a larger impact on quality than if it were to get rained on. NDF increases about 0.3 to 0.9 points per day of maturity, while rain can add 2 to 6 NDF points per day. For example, if rain is in the forecast and the farmer ends up waiting a week, this can equate to roughly a total loss of 6 NDF points, but if it rains, there is the potential to only lose 2 to 6 points. “It’s all a balancing act,” said the forage specialist.
The ideal time of day a farmer should cut is different for various parts of the country. For the northern states, Cassida suggested cutting in the morning. Forages accumulate sugar during photosynthesis throughout the day, making water soluble carbs their lowest at dawn and greatest in the evening hours. But photosynthetic drying cannot occur in the dark. Cutting in the evening boosted time needed for drying. This is why it is important to know your moisture content, as moisture is not uniform across a field. Cassida recommended using a Koster tester, probe, or implementing a moisture tester on the baler to keep moisture levels in check.
