Harvesting high-quality forage can be challenging during periods of rainy weather. To harvest quality dry hay, you need several consecutive days of favorable weather. When it’s wetter during early summer, it’s challenging to harvest and preserve quality forage from the first cutting.
Under these conditions, wrapping wet hay for bale silage is another option to preserve forage quality.
Rain on cut hay can significantly reduce quality and yield. Depending on amount and duration, rain after cutting can reduce yield and forage quality by up to 40 percent. The decline is likely greatest if the rain falls on dry hay and considerably less if it falls on freshly cut hay.
Waiting for better weather also reduces quality, but increases yield. Alfalfa yield increases about 100 pounds per acre per day in average growing conditions, except for the latest cuttings.
The quality of first cutting decreases at the fastest rate, while later cuttings change in fiber and digestibility at a slower rate. For example:
First cutting: Decreases about five points in relative feed value (RFV) per day.
Second cutting: Decreases two to three points per day.
Third or fourth cutting: Decreases one to two points per day.
Time of year
Forage quality changes little during late fall growth in mid- to late-September and early October. Relative forage quality (RFQ) will change at about the same rate as RFV on first cutting, and then decline about four points per day on the second, third and fourth cuttings during the growing season.
Large bale silage
To deal with potential losses in forage yield or quality, livestock producers have adopted large bale silage as a method of harvesting their hay crop. Silage bales, also known as baleage, that’ll store longer with less dry matter loss is one key to efficient harvest.
What to know about baleage
Baleage is an alternative to storing dry hay and may be exceedingly helpful during rainy periods of the haying season.
Silage bales are a flexible addition to most feeding programs, and it’s easy to transport them short distances. Feeding baleage is similar to feeding dry hay, but with less storage waste.
However, baleage may not be feasible if you need long-distance transportation to market the hay. Baleage can be as much as half water, so transportation costs often become excessive.
Optimal moisture content
The ideal moisture content for baleage is between 40 and 55 percent.
When the bales are wrapped, this’ll create a condition for proper fermentation and longer-term storage. Dry matter losses will be lower when harvesting at these moisture levels.
However, many producers end up with tough hay when moisture ranges between 20 and 35 percent. Bales in this lower moisture range should be wrapped to avoid spoilage, but they may not ferment as readily.
For all moisture levels, keeping the air out is key. It’s a bit like canning pickles or tomatoes: One will ferment and the other won’t, but the key to both is excluding the oxygen.
Plastic wrap thickness
Research in Wisconsin has found that at least 6 mils – and preferably 8 mils – of plastic wrap will cover the bale. To achieve this thickness, wrap the bale six times with 1 mil plastic or four times with 1.5 mils plastic.
With 4 mils of plastic, oxygen leaked through the plastic, which supports continued microbial growth and spoilage. Total plastic thickness, not the number of wraps, appears to be the most important factor in preventing oxygen from reaching the feed.
Line wrappers help reduce plastic costs and wrapping time compared to individually wrapped bales.
Timing: When to wrap
For optimal preservation, wrap bales within 24 hours using 6- to 8-mil-thick plastic.
In a Wisconsin study, bales were wrapped at 12-hour intervals up to 96 hours after baling. Bales left unwrapped or where wrapping was delayed more than 48 hours had internal temperatures exceeding 130 degrees Fahrenheit. These bales tended to have lower forage quality and greater mold throughout the bales.
Remember to make bales the size and weight for the wrapper and your loader.
Most wrappers have an optimum bale length of 4 to 6.5 feet. If bale moisture is quite high, these bales can be quite heavy, so be sure your loader can handle the extra weight.
Heavier bales also cause more problems with plastic tears and holes while wrapping, stacking and in storage. With continuous wrapping (sausage style), this may be less of a concern.
When you handle large, individually wrapped bales, use a bale grabber instead of a spear unless you plan to immediately feed them.
Storing silage bales
Place silage bales on a smooth surface free of sharp objects or crop stubble.
Mowing a grassy, well-drained area is a great place to store silage bales. Be sure the area is away from fence lines and other obstructions, so removal isn’t hampered.
Reviewed in 2018