By DAVID HARTMAN
Hay harvesting will start month after next for many farmers in Pennsylvania. If you are going to be storing hay as baleage, there are additional costs and potential benefits compared to harvesting dry hay. To capture all the potential benefits, we need to make sure we have the proper management in place to succeed.
The last few decades have brought increased interest in the use of plastic wrapped bales for forage. The advantages are clear: reduction in drying time, better leaf retention compared to dry hay, no storage structures needed, and reduction in weather risk. The added expenses are there too, and like most other things in the business of agriculture, it can be a game of figuring out what will pay in your particular farm situation. The last Pennsylvania Custom Rate Report put bale wrapping in a range between $7-8/bale. And there is a cost to disposing of the plastic. These include your time and hauling and landfill fees.
But, with very large numbers of white bales dotting the landscape around the state, many folks clearly see wrapping hay bales as a beneficial practice for their farm. One of the interesting things about the practice of using plastic to wrap bales is that the technology is well adapted to both small and large farms. The proliferation of farmers offering custom wrapping has helped make wrapping cost-effective for many farms that would not have been able to justify owning wrapping equipment.
We occasionally receive questions in regard to aspects of making and feeding quality baleage. For this article I did some checking around to see what research has been done in regard to wrapping bales.
The percent moisture at baling is often discussed. Most farmers seem to have their preference on moisture levels. Many farmers I have talked to prefer baleage a little on the drier side. In general, research on the topic has shown that ideally moisture should be in the range of 45-55%. This range creates the most favorable conditions for fermentation. Studies by the USDA-ARS (Coblentz, et al.) have shown almost no lactic acid production occurring in baleage below 42% moisture. Bales at lower moisture may have little to no fermentation, but wrapping protects them from spoiling. On the other hand, moisture levels too high can cause clostridial fermentation with resulting high levels of butyric acid and ammonia. This is the baleage that has a wet, slimy appearance and an awful smell. Baleage in this situation can be risky to feed to livestock.
Another question is how much plastic to put on the bale. To make quality baleage, air must be eliminated as much as possible from inside the bale. This first means making a tight bale. Furthermore, it means putting enough plastic on the bale to stop any movement of air into the bale. Research at the University of Wisconsin (Undersander, et al.) studied using 1.0 ml and 1.5 ml plastic and various numbers of wrappings. Internal bale temperatures were monitored and showed that bales wrapped with at least 6 ml of plastic (either four 1.5ml layers or six 1.0 ml layers) had an immediate temperature drop and reached ambient temperature in about 8-9 days. The researchers concluded that bales should receive at least 6 ml of total plastic. The total plastic thickness, not number of wraps, appears to be the most important factor.
Another question that comes up occasionally is how long can bales sit without being wrapped before quality could be compromised? During the rush of hay-making, the reality is that sometimes bales need to wait longer for wrapping than we would like to have happen. But how long is too long?
Another University of Wisconsin study (Undersander, et al.), wrapped bales at 0, 12, 24, 36, 48, 72, and 96 hours after baling. The researchers concluded that bales should be wrapped within 24 hours after baling to avoid the quality problems caused by the high internal bale temperatures associated with long delays in wrapping. Other studies have come to the conclusion that the critical point is perhaps closer to 12 hours. Factors such as moisture level at baling and the forage species being wrapped could play a role in this issue as well. Obviously your goal needs to be getting bales wrapped as soon as possible after baling. I would conclude that we need to get it done within 12 hours if at all possible. The second 12 hours up to 24 gets a little dicey. And if it gets beyond 24 hours, we can expect quality issues.
And finally, we sometimes get questions about whether or not sheep should be fed baleage. It is commonly known that sheep are more susceptible to the bacteria known as Listeria monocytogenes and can contract listeriosis or ‘circling disease’ more readily than cattle. Also, abortions are common in sheep and goats exposed to Listeria monocytogenes. For these reasons, some stock owners will avoid using baleage for sheep, some use it regularly and report no problems, and some will avoid bales that show any signs of mold. Experts recommend managing the baleage process to avoid getting soil in bales, since Listeria is a soil-borne bacteria. And, good fermentation is important to help prevent Listeria from proliferating.
The popularity of plastic wrapped bales seems to be here to stay. Like many other practices in modern agriculture, close management and paying attention to details is required for success.
Source : psu.edu