Paul Beck, professor at the University of Arkansas Southwest Research and Extension Center said that optimizing forage and silage quality is primarily about maturity of the forage they are harvesting, once the forage material is cut.
“The first step is to maintain proper harvest intervals and monitor forage maturity prior to harvest,” Beck added. “When baling or placing silage in the bunker it is also essential to achieve the proper moisture level. Excessively wet silages can undergo clostridial fermentation which leads to poor bunk-life, off-odors and flavors and ultimately cattle going off feed. Excessively dry silage can result in moldy product with short shelf life and reduced nutrient content.”
According to Robert Kallenbach, professor and state extension specialist for the Division of Plant Sciences at the University of Missouri, we have already passed the first harvest for cool season grasses, the second harvest should be cut at 10 to 12 inches high.
“Alfalfa should be cut at the first flowering stage,” Kallenbach said. “Warm season grasses, such as tall native grasses, should be cut at 16 to 18 inches high. Shorter grasses should be cut every 28 days.”
Beck said, “As a rule of thumb round-bale silage should be wrapped within four hours of baling, but there is data indicating that most of the reduction in quality occurs after a 24-hour delay. Legume crops depend on leaf retention to maintain high forage nutritive value, if baling as hay care should be taken to maintain leaf content in the bale and not shatter leaves on the ground.”
In addition, make sure bales are packaged tightly and not too big. “When chopping silage, the pieces should be cut into 1/2 of an inch length,” Kallenbach said.
When wrapping bales in plastic, the bales should have two full turns in the wrapper. “Hay should be baled at approximately 50 inches high,” Kallenbach added. “An ideal size for silage bales is 4 foot x 4 foot.”
According to Beck, it is important for producers to test silage for protein, fiber content (NDF and ADF), digestibility and fermentation acid profiles.
Beck also said that fiber content is important because neutral detergent fiber (NDF) can have large impacts on forage intake; acid detergent fiber (ADF) can have impacts on digestibility of forage; and forages are fed to supply roughage in the diet measured as NDF or effective NDF… this must be maintained for ruminal health of the dairy cow.
“Digestibility (lab procedure is In Vitro Dry Matter Digestibility) is the best estimate of the actual energy content other than animal performance after the forage is fed,” Beck added.
The fermentation profile is an indication of the quality of the fermentation of the silage material and will indicate if the silage was put up properly.
According to Kallenbach, bales should be stored for at least 6 weeks, and will keep a good level of quality up to 16 months. They also need to be kept where there is good drainage.
He also added that one of the major things that can ruin hay and silage after wrapping bales is holes in the plastic. “If there is a hole the size of a quarter in a silage bale, there is a basketball size worth of damage behind that hole.”
