Bushel

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Conversion table for the equivalent mass per bushel. USA circa 1854

The bushel is an Anglo-American unit of measurement originating from the British Isles for determining the volume of goods. The word Bushel is an Anglicification of the old French boissiel and buissiel "Fässchen". This unit is abbreviated with bu or bsh . A typologically comparable unit of measurement is the bushel .

Although the bushel is actually a measure of space, it has also been used as an equivalent measure of weight for certain goods, such as apples. For this purpose, conversion tables were issued which - depending on the type of goods - determined the bushel weight , i.e. the mass that corresponded to a bushel of a certain type of goods.

Nowadays the bushel is only used as an equivalent grain measure in the United States ; this unit has practically no other application.

There is the - now historical - British bushel (imp bu) with roughly 36.4 liters and the US bushel (US bu), which is roughly 3% smaller with roughly 35.2 liters.

British bushel

Queensland Government Standard Imperial Bushel, Queensland Museum

1 bu = 36.3687 l

With the Weights and Measures Act of 1963 and 1976, the British system of measure of measure was adjusted and, among other things, the bushel was abolished. This bushel was defined in the Weights and Measures Act of 1824 as eight times a gallon . The British Imperial Bushel was only used in bulk goods (e.g. grain, coal, fruit), although it was derived from the gallon, which is applicable to both bulk goods and liquid goods.

American bushel

1 bu = 35.23907016688 l

In the USA the bushel has its origin in the historical English Winchester bushel, which at the time of its abolition in England in 1824 corresponded to a cylindrical volume with a diameter of 18½ inches and a height of 8 inches. The US bushel was derived from this unit and defined with exactly 2150.42 cubic inches, which is around 1.1 liters smaller than the British bushel, which has since been abolished, and in contrast to it is in no proportion to the gallon. The American bushel is only used for bulk goods and is the basic dimension for the nowadays uncommon system of dimensions for bulk goods (dry measure).

Used as a unit of account for grain in the USA

In trade (e.g. on commodity futures exchanges ) the bushel is now used as an equivalent weight measure. The mass of a bushel depends on the type and moisture content of the grain. Since the USA is one of the largest grain producers, the unit "bushel" is important worldwide as a measure of the mass of a quantity of grain. Nowadays, when grain prices are given per bushel, this “bushel” is meant.

A "bushel" (as a unit of mass) of a certain type of grain corresponds to the mass of a quantity of grain with the volume of a "bushel" (as a unit of volume), assuming a defined moisture content .

The mass, which corresponds to the amount of a “bushel” grain, is called “standard weight per bushel” or “standard bushel weight” or “standard weight”. The basic moisture (= reference moisture) at which the "standard bushel weight" can be determined is called "standard moisture".

In the metric system of measurement , the accounting unit "bushel" (as a measure for determining the amount of grain) is comparable to the so-called dry matter in grain, which is calculated based on the actual mass and moisture content as well as the basic moisture of the dry matter.

Definition and conversion table for the US grain measure "bushel" (abbreviated: bu)
Type of grain standard moisture
(basic moisture)
standard bushel weight Area yield Grain price
pound (lb) → mass (kg) bu / acre → dt / ha $ / bu → $ / t
Corn 15.5% 1 bu = 56 lb ≈ 25.401 kg 1 bu / ac ≈ 0.6277 dt / ha 1 $ / bu ≈ $ 39.3683 / t
wheat 13.5% 1 bu = 60 lb ≈ 27.216 kg 1 bu / ac ≈ 0.6725 dt / ha 1 $ / bu ≈ $ 36.7437 / t
rye 14.0% 1 bu = 56 lb ≈ 25.401 kg 1 bu / ac ≈ 0.6277 dt / ha 1 $ / bu ≈ $ 39.3683 / t
barley 14.5% 1 bu = 48 lb ≈ 21.772 kg 1 bu / ac ≈ 0.5380 dt / ha 1 $ / bu ≈ $ 45.9296 / t
Soybeans 13.0% 1 bu = 60 lb ≈ 27.216 kg 1 bu / ac ≈ 0.6725 dt / ha 1 $ / bu ≈ $ 36.7437 / t
oats 14.0% 1 bu = 32 lb ≈ 14.515 kg 1 bu / ac ≈ 0.3587 dt / ha 1 $ / bu ≈ $ 68.8945 / t

Determination of the billing amount in bushels

To determine the amount of grain charged in "bushel", the grain is weighed and the moisture measured. If the actual moisture is higher than the basic moisture ("standard moisture") of the respective grain type, the equivalent dry matter must be calculated as follows:

Dry matter at reference moisture = mass × (100% -% moisture) / (100% -% reference moisture)
Note: The percentage of grain moisture is defined as the ratio of the mass of the water contained in the grain sample to the total mass of the grain sample.

In the next step, the dry matter is divided by the “standard weight per bushel” and the number of “bushels” is obtained.

  • Example: How many units of weight “bushel” make 1000 pounds of maize (≈ 453.6 kg) with a determined grain moisture of 30%?
First of all, the dry matter must be determined for the reference or basic moisture of 15.5% valid for corn: 1000 pounds × (100% - 30%) / (100% - 15.5%) = 828.4 pounds (≈ 375, 8 kg) dry matter
The calculation unit "bushel" results from the dry matter by dividing by the so-called "standard weight / bu" of maize (= 56 pounds): 828.4 pounds / 56 pounds = 14.8 bushel maize or abbreviated: 14.8 bu corn.

Bushel as a basis for determining the bulk density of grain

The grain price for a certain amount is not only dependent on the dry matter (based on a basic moisture content), but also on the bulk density , which in German-speaking countries is referred to as the hectolitre weight for grain . The determination of the bulk density is the only application in which the unit "bushel" is used as a measure of space . Here a measure of capacity with the volume of a "bushel" is filled with grain that has the basic moisture. The determined weight gives a measure of the bulk density and is referred to as “test weight / bu” or also as “test weight”. Ideally, the “test weight / bu” matches the “standard weight / bu”.

Bushel as the basis of area yield

In North America, the area yield (English: "yield") of grain is given as "bushel / acre ". When converting "bushel / acre" to the metric area yield unit "dt / ha ", it should be noted that this initially applies to the specified basic moisture ("standard moisture") of the respective grain type and for other basic moisture levels for the target unit "dt / ha" is to be converted accordingly.

Bushel as a basis for price information

In the United States of America, all types of grain are priced in "$ / bu" . The grain price in "$ / bu" determined by the Chicago Board of Trade is a globally recognized price indicator.

Individual evidence

  1. Bushel . In: Oxford English Dictionary .
  2. Weights and Measures Act of 1976 (UK) page 14: List of the valid English measures of measure.
  3. "Weight and Measure Act 1824 (UK)"
  4. ^ Weights and Measure Standards of the United States. In: National Institute of Standards and Technology (Ed.): Publication 447
  5. Tables for Weights and Measurements: Crops University of Missouri , accessed January 30, 2017.
  6. Wet Basis Moisture Content (moisture content) Purdue University , Indiana / USA, accessed on January 31, 2017.
  7. Corn Grain Test Weight Purdue University , Indiana / USA, accessed January 30, 2017.