Bale shapes and sizes

The best moisture level for baling hay or green feed depends on the type of baler you use. If you have a large hard-core round baler, 15% moisture is optimum. At this moisture level, the bales will keep for an extended period.

Table 1. Bale size to moisture contents

*The lower moisture range is preferred in areas of low humidity. Higher moisture percentage is best for other areas.
Source: Adapted from an article presented at the Alfalfa Intensive Training Seminar, National Alfalfa Alliance, Salt Lake City, Utah, March 2 to 4, 2004, Dr. Mike Collins, University of Kentucky.
Bale Shape Height, ft Width, ft Length, ft Volume, ft3 Typical weight, lb Safe baling moisture, %
Rectangular 1.2 1.5 3.2 5.5 60 18-20*
Rectangular 2.7 3 7 56 900 12-16*
Rectangular 4 4 8 112 1800 12-16*
Round 4 -- 4 50 500 15-18*
Round 4 -- 5 63 850 15-18*
Round 5 -- 4 79 1000 15-18*
Round 5 -- 5 98 1300 15
Round 6 -- 5 141 1900 15

Higher moisture levels

When moisture levels are higher than those shown in the table above, there will be:

  • excessive heating in the bales
  • mould growth
  • loss of large amounts of dry matter

Moulds consume nutrients and generate heat as they grow. If the hay reaches 55 degrees C or higher, severe browning reactions begin.

Amino acids and sugars combine to form insoluble nitrogen compounds that are unavailable to animals. These reactions increase the amount of insoluble fibre. This leads to a lower digestibility or total digestible nutrients.

These reactions may also lead to spontaneous combustion.

Mould organisms under heat stress may produce toxins. These can be harmful to livestock and may reduce intake. Moulds also produce spores that, if inhaled, can cause lung disease or exacerbate existing respiratory problems.

Heating in bales occurs to some extent unless the feed contains less than 15% moisture.

For more information, see:

Contact

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Hours: 8 am to 5 pm (open Monday to Friday, closed statutory holidays)
Toll free: 310-FARM (3276)
Phone: 403-742-7901 (outside Alberta)
Email: aginfocentre@gov.ab.ca