For some producers, silage is a mainstay, but for others who may be new to the process, there is a learning curve.
Regardless of experience, there are several variables producers must consider when ensiling a crop. Gains or losses can occur during seeding and feeding silage. However, management during harvest may be pivotal to promote successful fermentation and achieve high-quality feed.
Karen Beauchemin, a ruminant nutritionist with Agriculture and Agri-Food Canada at Lethbridge, Alta., has been studying the nutritional aspects of silage for years.
“Silage will give you a feed supply over winter that is a uniform material and uniform quality,” Beauchemin says. “It can be easy to feed out.”
Beauchemin adds that silage blends into a ration with other ingredients more readily than hay. An additional benefit is the potential for high dry matter yields and the ability to produce more feed on fewer acres.
Lindy Greig, owner and operator of 3G Custom Silaging from Nanton, Alta., says producers are starting to take a closer look at how silage may work for them. Many of his customers are long-time silage proponents but he estimates about 30 per cent of his customer base are relatively new to the process.
“The cost of hay has opened people’s eyes to looking at different crops, and they are stepping out of their lane and starting to research the benefits of silage,” Greig says. The cost for the quality of feed is an advantage, he continues, and a properly sealed silage pile will last for an extended period of time with few losses relative to hay.
Beauchemin says that success with silage relies on many factors.
“You’re depending on a fermentation process, which can work to your advantage,” she says, but adds that a crop harvested when too dry or too wet can lead to losses and waste.
“You have a lot of material, a lot of money invested, and you can have a poor-quality feed in the end if you don’t have proper fermentation.”
Expected (and unexpected) crops
Corn or barley crops contain a lot of soluble carbohydrates and are typically easier to manage for silage. These crops, with their high starch levels, often ferment quickly with minimal loss. Compared to corn or barley, alfalfa has relatively low sugar content, making it a challenging crop to ensile.
“With alfalfa-grass that is harvested wet and then ensiled, you can get a lot of seepage and loss of dry matter,” Beauchemin explains, adding that clostridia bacteria may start to grow, and butyric acid levels can rise. This results in poor fermentation, reduced protein plus palatability and feeding issues.
Greig says his custom harvest business will ensile any type of crop, although barley or a barley-oat combination is most common on dryland.
“Triticale has come on big in the past few years,” he says, adding he also chops a lot of corn, especially on irrigated land. He notes that canola, sorghum and weedy fields as examples of some unique crops they’ve harvested.
“If you have an ‘oops’ crop, you can still silage and mix it off and feed it,” he says, which allows producers to capture as much nutritional value as possible.
“You can ensile almost anything,” Beauchemin agrees. In the past year she has had some conversations with producers interested in turning sugar beets into silage. She has experience blending sugar beets with drier product such as straw but said you must understand the moisture level of the products you are working with.
“When you start out with a really wet crop you may need to dilute wet product with drier material,” she says. She cautions that when mixing, you want to avoid creating layers of wet and dry.
“You want to get a good mix to reduce pockets of spoilage,” she says.
Inoculant is important
The target moisture level for silage is 60 to 70 per cent wet matter. “Preferred moisture is around 65 per cent, but I prefer anywhere from 63 to 68 per cent. As a custom operator, there is always a push and pull,” Greig says.
Greig samples each load for moisture during harvest, selecting from the front, middle and back. He also promotes the use of inoculant, which is applied during chopping and costs around $1 to $1.50/ton.
“I haven’t done the research on it but I believe in inoculant,” he says, adding that they keep piles over for a year or longer without spoilage.
Beauchemin says that science clearly favours inoculant.
“If you look at your cost-benefit ratio, it’s always better to use an inoculant, especially if you have drier silage.”
She recommends using a third-generation inoculant with Lactobacillus buchneri to help kick-start fermentation. It can also help with the feed-out period.
“A dry silage is prone to getting yeast growing on it in the feed bunk. Incorporating an inoculant can minimize the yeast and maintain palatability.”
Harvesting tips for optimizing quality
Beauchemin and Greig both emphasize the importance of aiming for the correct chop length and using a kernel processor when harvesting corn.
“For corn, I recommend chopping it to around 0.75 inches long but if your corn silage is drier, reduce the chop rate to 0.5 inches to ensure you get proper packing,” Beauchemin says.
Splitting cobs into eight or more fragments and processing kernels into 0.25 inch-long pieces promotes good packing and makes corn starch available in the rumen rather than passing through the animal, Beauchemin explains.
“Length of cut is a huge thing — not only for sifting when feeding it out to cattle but also for packing,” Greig says. A consistent chop length means there are no air pockets and waste will be limited. Silage can be packed in an above-ground pile or a structure, but Greig prefers open-face above-ground piles because they are safer and tend to have less spoilage.
Both research and experience suggest that producers should cover their fermenting silage. “I think it’s a preference on how much spoilage you’re willing to accept, but with the winds we have, I believe we need to tarp with plastic,” Greig says.
Beauchemin says there are many studies that demonstrate economic losses due to poor fermentation and spoilage if silage is exposed to the elements.
“You put so much time and money into growing your silage, the last thing you want to do is end up with poor-quality silage or dry matter losses and having to throw away all the spoiled material,” she says.
Some producers use bales, manure, or dirt to help seal the bottom and place tires on top of plastic. Greig mentioned that he has heard of customers spraying a molasses supplement on the silage, which worked as an oxygen barrier; however, it unfortunately attracted wildlife.
Harvesting a crop for silage can be a major investment and a way to preserve as much nutritional value per acre as possible. Producers can protect their investment and achieve a nutritional feed source as long as they are careful to harvest their crop at the right stage of maturity and moisture content, chop it at the correct length, apply inoculant, and seal the deal by covering their silage to promote a successful fermentation.