Hay specific weight: weight in bales, rolls and stacks
When preparing feed reserves for winter, it is important to know their weight, because a properly balanced diet in livestock farming is the basis for weight gain and herd growth.
The main feed component for cattle and small ruminants is hay. It can consist of different plants that determine feed nutritional value and preservation. In order for plant feed collected for winter to contain the maximum amount of useful elements, grass mowing must be carried out according to certain rules. Mown and dried hay is collected in stacks, ricks or pressed into bales or rolls.
How to Determine the Weight of a Haystack?
Hay is stacked manually in ricks. Over time it settles and becomes denser. The weight of a haystack can be determined if its approximate density is known, meaning how many kilograms fall on 1 m3, as well as the volume of the rick. It should be noted that mass values are averaged, because hay weight is affected by moisture, stack height and settling time.
Example values:
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Hay consisting of sown cereal-legume herbaceous plants after the first month of storage in a rick will weigh 60 kg/m3, and after three months of settling, 70 kg/m3.
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Mixed grasses collected from floodplain meadows will have a cubic meter mass of 35 kg at the beginning of storage and 50 kg after the third month.
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Sown cereal grasses will weigh 45 and 60 kg respectively.
The table can be used to determine how much 1 m3 of hay placed in storage or gathered into a rick weighs depending on its height. Multiplying the listed values by the area of the rick or storage gives the hay weight.
| Hay type | Stack height (m) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | |
| Sown legumes | 50-53 | 53-57 | 55-60 | 57-62 | 59-64 | 61-66 | 63-68 | 65-70 | 67-72 |
| Cereal-legume hay | 40-47 | 48-50 | 50-52 | 52-54 | 54-56 | 56-58 | 58-61 | 60-64 | 62-67 |
| Perennial cereals | 40-42 | 41-44 | 43-46 | 45-48 | 47-50 | 49-52 | 51-55 | 53-57 | 55-60 |
How to Determine the Weight of a Hay Roll?
Mown grasses are collected and pressed into rolls by a special unit, a baler. The machine operator sets the tamping density. It may differ depending on how well the hay has been dried. Bales are compacted at a density of 100 kg/m3 when the hay needs to mature and evaporate a little more moisture. The maximum density of a baler is 200-250 kg/m3.
By shape, hay may be:
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rolls;
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small bales;
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large bales.
Not every hay bale can be visually determined or measured on special equipment. The weight of pressed bales and rolls is very large, and there is usually no special need for this because balers produce relatively uniform bales.
To determine the weight of a hay roll, it is necessary to know the circumference and width of the roll. Pressing density and drying quality of the grass also matter. The table shows some average weights of round rolls.
| Roll diameter / length (m) | 1.2 | 1.4 | 1.5 |
|---|---|---|---|
| 1.1 | 120-200 | ||
| 1.2 | 150-250 | ||
| 1.4 | 180-270 | 240-330 | |
| 1.45 | 220-375 | ||
| 1.5 | 320-500 | ||
| 1.8 | 450-700 |
The standard weight of a hay bale measuring 90x50x35 cm is 15-20 kg. Smaller packaging also exists:
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38x53x30 cm weighs 5-6 kg;
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52x53x30 cm weighs 10-12 kg.
Large rectangular bales weigh approximately 300-350 kg depending on pressing quality and grass drying.
The average mass is determined by multiplying bale volume by the density of pressed hay, equal to 200-250 kg/m3. To determine bale weight accurately when purchasing, it is recommended to weigh them on special weighing platforms.
Frequently Asked Questions
Can the density of hay be used for precise calculations?
The density and weight values for hay in this article are reference values. They are suitable for preliminary estimates, but design, construction, production and other critical calculations should be checked against standards, material datasheets or measurement results.
Why can the actual weight of hay differ from the table?
The actual weight of hay depends on composition, moisture, temperature, porosity, fraction size, material grade and measurement conditions. Because of this, real values may differ from the average table data.
How do you calculate the mass of hay from density?
For an approximate calculation, use the formula: mass = density × volume. If the density of hay is given in kg/m³ and the volume is in m³, the result will be in kilograms.