By Robert Fears
Baled silage -- also called haylage, baleage or round bale silage -- offers an opportunity to harvest and preserve forages at optimum productivity and quality.
These growth stages often occur when moisture content is too high for hay harvest and too low for ensilage. As a solution, producers are turning to baled silage. In addition to its high quality, advantages include flexibility in handling and feeding, limited capital expenditures, low production costs and minimal nutrient loss.
“Haylage is cut forage sealed in a plastic sleeve,” explains Rocky Lemus, extension forage specialist at Mississippi State University. “Forage harvested as haylage requires 40-60% moisture with a targeted average of 50%. This is an intermediate level between optimum moisture contents for hay and silage.:
Proper time for making haylage of annual grasses such as sudangrass, sorghum-sudan hybrids, millets and annual ryegrass is at the boot to early head stage, Lemus says. Small grain haylage such as oats, wheat and barley, is best harvested at the boot to early dough stage.
Lemus adds that ensiling high nitrate forages like Johnsongrass as baleage can reduce the nitrate content by as much as 50%, which also reduces the risk of nitrate poisoning.
Wrap to form a tight seal
Basically, haylage is harvested like hay except for wrapping bales in plastic with a wrapper pulled behind the baler.
In addition to harvesting at the proper time, it is important to correctly wrap haylage to form a tight seal of the plastic. An airtight environment, plus high moisture content, causes the forage to ferment. The forage is preserved by lactic acid production during fermentation.
“Level of fermentation is influenced by moisture content of the forage,” Lemus explains. “It is advisable to start baling haylage in the morning at a moisture content range of 50-60%, since the material dries as the day progresses. Moisture levels are maintained after cutting by using a high-density baler and quick wrapping of the bales.”
The compaction provided by high-density bales reduces the presence of oxygen and creates an anaerobic environment, which limits mold growth.
Sealing the bales within a few hours of bailing prevents secondary air movement into the bales. Wrapping should occur ideally within five hours of baling. Delaying the operation beyond 10 hours results in a slower fermentation process.
“A recommended thickness for plastic wrap is four mils,” Lemus says. “If bales are fed more than a year after harvest, a thickness of eight mils is suggested. Plastic film must have a 50% stretch factor, ultraviolet light resistance, good tear strength and good adherence capability. White plastic is used for high sunlight areas and black for lower sunlight areas.”
Use a 50% overlap of the plastic to provide a sealed environment. Wrap bales tightly and ensure that the plastic is stretched and has formed a tight seal. If bales are not sealed properly, oxygen may continue to enter the system. This continued respiration and heat production can seriously damage your baleage. Temperatures over 112 degrees damage forage protein, making it unavailable to livestock.
Lemus explains it is important to decrease bale size, too, since baleage is much wetter and therefore weighs more than dry hay. The most common round bale sizes are four feet by four feet or four feet by five feet.
“These bales weigh 900 to 1,300 pounds depending on density and moisture concentration. Producers can make larger bales that require less plastic per cutting,
but it is highly discouraged because of handling difficulties,” Lemus explains.
Handle with care
You must store haylage in a manner to avoid breaking the seal. Clean any crop stubble or other sharp objects that could potentially puncture the plastic wrap from the storage area. Laying a piece of plastic on the ground prior to depositing the bales on its surface helps protect the seal. Spray the perimeter of the storage area to control weeds that could harbor rodents and insects which might chew through the plastic wrap.
Quality and advantages of haylage are maintained only if it is tightly sealed until fed. If these are lost, then you have only incurred extra expense and achieved no added quality, or worse.
Fears writes from Georgetown, Texas.