What is a bushel?

A bushel is a common unit of measure in the U.S. grain market, especially in commodity exchanges like the Chicago Board of Trade (CBOT), for crops such as corn and soybeans. It belongs to the U.S. customary system of measurement and is different to the metric system used globally.

History of the bushel as a unit of measurement

The imperial system is derived from the English System of Measures and Units, which evolved from ancient Roman, Carolingian, and Saxon measurement traditions. During medieval times, farmers used volumetric units like bushels and gallons to trade agricultural goods. Over time, however, the size of a bushel varied depending on the region and type of product being measured.

In the early 19th century, commodity measurement systems were highly varied and lacked standardization. Bushels were originally based on the ‘dry gallon’ of 268.8 cubic inches, but different versions existed. In 1824, the British Weights and Measures Act set the bushel at 8 imperial gallons (277.3 cubic inches). Over time, further updates refined these measurements until the UK’s 1897 Weights and Measures Act, which remained largely unchanged until after World War II.

In the United States, the English measurement system was used until independence in 1776. After that, the U.S. Constitution granted Congress the power to set standards for weights and measures. Still, for many years, the measures used were the same as those from England. At some point, adopting the metric system was considered, but no action was taken until 1832 when the Treasury Department officially defined key measurements – such as yardsticks, pounds, gallons, and bushels – for customs purposes.

By the 20th century, bushel standards in the U.S. varied by state and were often based on weight (mass) rather than volume, depending on the commodity. This inconsistency caused issues in commercial transactions. In 1905, the newly established National Bureau of Standards organized a meeting, now known as the National Conference on Weights and Measures (NCWM), to address these discrepancies.

In 1915, the first standardized definitions were published, but the bushel was still inconsistent across different markets. The Chicago Board of Trade (CBOT) eventually adopted specific definitions of bushels for different commodities: a bushel of corn weighed 56 pounds while a bushel of soybeans and wheat weighed 60 pounds. This means the bushel is a volumetric measure which is influenced by the density and characteristics of the product  being measured.

This CBOT definition of bushels remain in use today:

• 1 bushel of corn = 56 lbs = 25.40 kg
• 1 bushel of soybeans or wheat = 60 lbs = 27.22 kg.

How is a bushel used as a dry measure in agriculture?

In the United States, bushels are used to measure dry capacity of products, unlike in the United Kingdom where they can be used to measure both dry and liquid products.

In agriculture, bushels are used to quantify bulk commodities like grains, fruits, and vegetables. Farmers and traders in ag operations use bushels to measure corn, wheat, soybeans, barley, and oats. Since the density of each grain varies, standard weight equivalents are used: 

• 1 bushel of corn = 56 pounds = 25.40 kg
• 1 bushel of wheat or soybeans = 60 pounds = 27.22 kg
• 1 bushel of oats = 32 pounds = 14.51 kg
• 1 bushel of barley = 48 pounds = 21.77 kg.

 Bushels are also used to measure and report crop yields during harvest. For example, a cornfield might yield 180 bushels per acre, meaning each acre of land produces about 10,080 pounds (4,564.5 kg) of corn. They are also used in storage planning to measure the capacity of a grain container or silo.

 In commodity markets, like the CBOT, agricultural commodities are priced in bushels. For example, the market prices of wheat futures might be quoted as $5.53 per bushel.

What does a bushel mean for different crop types?

The weight of a bushel varies by crop. Below are some of the most common agricultural commodities and their weight in bushels: 

The importance of bushels in commodity pricing and trade

Bushels are often used to price agricultural commodities. For example, futures contracts on the CBOT are often quoted in cents per bushel (e.g. $5.50 per bushel of corn) and by bushels per contract (e.g. 5,000 bushels per corn futures contract).

Not all commodities are priced in bushel, however, and some – such as rice, flax seed, and cotton seed – are more commonly priced in hundredweight (CWT) or per metric ton (MT).

What industries use the bushel as a standard unit of measure?

The bushel is primarily used within the agricultural industry, particularly those involved in producing grains and seeds. It’s also used in agricultural commodity markets to provide consistent pricing for certain commodities.

The food processing industry also uses bushels when estimating quantities of raw materials, such as wheat or corn. Industries involved in agriculture-related research might also use bushels when assessing crop yields or inventory.

How does the bushel compare to other dry measures in global trade?

Unlike metric-based units like kilograms or tons, which are used globally and part of the International System of Units (SI), the bushel is part of the U.S. customary system. In global markets, the metric system is the most common unit of measure, so products sold in bushels in the U.S. often need to be converted to metric measurements for international trade.

Here’s how the bushel compares to the kilogram:

Here’s how many bushels are needed for one metric ton:

What are the challenges of using bushels in international markets?

The key challenges of using bushels in international trade is that there can be inconsistencies in how bushels are defined in different countries or regions.

For example, the U.S. bushel – known as the Winchester bushel – is defined as 35.24 liters while the UK bushel – known as the imperial bushel –is slightly larger at 36.37 liters. The imperial bushel is also used in Canada. These variations can cause discrepancies in trade when commodities are sold internationally, particularly in regions like Europe or Asia that do not typically use bushels. 

Another challenge of using bushels in international trade is that the weight of a bushel can vary depending on the density of a commodity. For example, as we’ve seen in the charts above, a bushel of corn weighs more than a bushel of wheat. This lack of standardization can make it difficult to compare trade volumes or prices across different crops.

Key considerations for businesses using bushels in trade contracts

Below are some things to consider for businesses using bushels in trade contracts: 

• Clearly define the bushel standard: Since the bushel can vary depending on country or region (e.g. US Winchester bushel vs UK imperial bushel), be sure to clearly define which bushel standard is being used in the contract.
• Convert to metric measurement: It might also be worth converting the bushels to metric tons or kilograms to avoid confusion or disputes in markets that are unfamiliar with the bushel system. This helps ensure that everyone is on the same page.
• Consider the moisture content: Moisture content can affect the quality and weight of agricultural products, particularly for crops like wheat or corn. It's a good idea to include clauses that account for standard moisture content and how the value of goods will be adjusted if moisture content differs from agreed levels.

How do fluctuations in bushel-based pricing affect supply chain decisions?

Fluctuations in bushel-based pricing can affect supply chain decisions by influencing when and how much of a commodity businesses choose to buy, store, or sell.

For example, if the price of wheat increases, businesses might decide to purchase less or delay their orders to avoid higher costs. On the other hand, if prices decrease they might buy more to take advantage of the lower price. For farmers and producers, solutions such as wheat risk management can help mitigate risks associated with price movements, currency fluctuations, and changes in supply and demand.

This material is for informational purposes only and should not be considered as an investment recommendation or a personal recommendation.