What do you do when the weather conspires against you and hay refuses to dry?
One form of storage that has gained popularity in the last couple of years is round baled silage, also known as haylage, which either comes in individually wrapped bales, or in tubes.
“When making haylage it’s imperative that bales are wrapped to maximum density to minimize air pockets in the bale. Moisture content for baled silage should be from 40 to 55 per cent for safe storage and adequate fermentation. Too much moisture and the bales become frozen solid in the winter. Too little moisture can result in excessive spoilage and limited fermentation activity. Don’t make the bales full size (they must be 2/3 – ¾ the size of a hay bale) as they can get too heavy for some loaders to lift.”
One of the advantages of baled silage is the reduced leaf loss in the hay and maintaining higher feed quality, says Brook. “The biggest plus, of course, is that you are not at the mercy of the weather. It allows you to harvest hay when it is ready, rather than waiting for a dry spell that may be too late in coming to get it baled. Quality hay is more about the physiological age of the hay when cut than the fact rain may or may not have fallen on it once it has been cut.”
To make sure you get the best quality in your haylage, the crop should be cut when young (early bloom stage for grasses and legumes), and left to wilt to the correct moisture over one or two days. It should be wrapped within 5 to 10 hours after baling, as spoilage greatly increases if the time lag is longer. “Use good quality plastic that creates a complete seal and prevents air from getting into the bale,” says Brook. “The whole secret to making good silage is to minimize the number of air pockets in the bale and preventing any air from getting into it once wrapped.”
The ensiling process is basically pickling the forage for long-term storage. Once wrapped, oxygen consuming bacteria use up the available oxygen in the bales. Too much oxygen will result in excessive heating. After the oxygen is used up, anaerobic bacteria use up the sugars in the forage and excrete lactic acid. Increased lactic acid lowers the pH, thus pickling or fermenting the forage. “Once ensiled, it’s important to prevent any air from getting back into the bale, as spoilage will occur. Any breaching of the plastic with tears or holes must be repaired immediately. When opened, baled silage stays good for only about a week. Tubed bales last about the same length of time.”
If hay is not dry enough for dry, baled hay, but too dry to make silage, propionic acid can be used to prevent mold growth. “Adding it to damp hay will prevent mold growth, which then causes heating and feed quality losses. It’s a way to give the bale time to naturally dry down to a safe storage level. The propionic acid solution is sprayed onto the swath as it enters the baler. The amount needed depends on the moisture level of the hay. The higher the moisture of the bale, the more acid will be needed.”
A moisture probe is can be invaluable for determining moisture levels in the hay. “It’s a good idea to have one on hand when baling. The probe will help you determine the correct rate of propionic acid needed as there can be varying levels of moisture in the field. Propionic acid is highly acidic and very corrosive on machinery, thus it is best to get it as a buffered solution. Some products claim they will treat hay up to 35 per cent moisture, but economically the propionic acid should be used on hay at 25 per cent moisture or lower. Treated hay is safe to feed to livestock.”
Using this acid makes economic sense in conditions where you want to avoid rain damage to almost dry hay, says Brook. “It can be very valuable especially when dealing with unsettled and intermittent rainy weather during the hay season. However, trying to make silage from nearly dry hay doesn’t work, even if it has been rained on. It will be too dry and not ensile properly, and will lose feed value.”
“There are alternatives for these challenging weather conditions. Their costs are higher, on a per tonne of dry matter basis, but can allow you to harvest hay when weather causes problems. Take a look at your situation and use the appropriate hay harvesting solution that fits your operation and budget.”