Source: Indiana Grazing Bites newsletter
Storage losses from big bales can be huge. John F. Grimes, an Ohio State University Extension Beef Coordinator, says dry matter losses are as follows:
• Conventional shed: 4-7%;
• Pole structure with plastic roof on pad: 4-7%;
• Reusable tarp on pad: 4-7%;
• Bale sleeve on ground: 4-7%;
• Plastic wrap on ground: 4-7%;
• Elevated stack on pad (rock plus filter fabric): 13-17%;
• Net wrap on ground: 15-25%;
• Stacked on ground: 25-35%.
Aside from constructing buildings for hay storage, there are some key points to remember to help reduce storage losses. Consider the following:
1. Hay/soil contact is typically the primary source of losses associated with hay stored outdoors. Cover your storage area with rocks 1-3 inches in diameter piled 4-8 inches deep. Using geotextile cloth below the rocks will increase the life of the pad.
2. If placing bales on the ground cannot be avoided, make sure a well-drained area is selected.
3. Hay should be stored in an open area that can receive maximum sunlight. Hay should never be stored under trees. It is also preferable to orient bale rows to run north and south to allow for maximum daily sun exposure.
4. Bales should be placed so the sides of the bales do not touch. Allow at least three feet of space between rows to allow for air circulation. An exception to this would be if you are stacking bales in a pyramid fashion for covering with a tarp or other material.
5. The flat ends of bales should be firmly butted against one another as this can protect the ends almost as well as if they were one continuous bale.
The bottom line is that cattle producers need to do a better job of preserving hay in order to ensure adequate supplies of quality feeds.
You can read more information here.