The Intense Heat Of Smudge Pots: A Cautionary Tale

A smudge pot, also known as a choofa or orchard heater, is an oil-burning device used to prevent frost on fruit trees. It typically has a large, round base with a chimney in the middle. The burning oil creates heat, smoke, carbon dioxide, and water vapour, protecting the orchard from cooling too much during cold snaps. While smudge pots have fallen out of favour due to rising fuel costs and environmental concerns, they were once a common sight in citrus groves and vineyards. They can heat an area of about 15 feet in radius and can run for 1.5–2 hours per gallon of diesel fuel.

A smudge pot can get hot enough to protect orchards and vineyards from frost

A smudge pot, also known as a choofa or orchard heater, is a device used to prevent frost on fruit trees in orchards and vineyards. It has a large round base with a chimney protruding from the centre and burns fuel, such as oil, kerosene or diesel, to produce smoke, heat, carbon dioxide and water vapour.

The smudge pot is placed between trees in an orchard or vineyard and ignited when the temperature reaches 29 degrees Fahrenheit (-2 degrees Celsius). For each additional degree drop, another hole is opened on the control cap ("draft regulator") to enhance the heating effects. The smoke from the smudge pot creates a blanket that reduces heat loss around the trees. This can protect the trees from potentially damaging frost during cold snaps.

The use of smudge pots became widespread after a disastrous freeze in Southern California in 1913, which wiped out an entire crop. They were commonly used for seven decades in areas such as California's citrus groves and vineyards. However, their use declined in the 1970s due to rising oil prices and environmental concerns.

Today, smudge pots have been largely replaced by smokeless burners fuelled by natural gas. However, they can still be used for decorative purposes or as a source of heat during outdoor gatherings, such as garden parties.

They can heat a radius of 15-30 feet

A smudge pot, also known as a choofa or orchard heater, is a portable device that burns fuel to produce heat and smoke. It is used to prevent frost on fruit trees and to provide heat in outdoor spaces. The amount of heat generated by a smudge pot can vary depending on several factors, including the type of fuel used, the outdoor temperature, and the elevation.

Smudge pots typically have a round base that holds the fuel and a chimney that releases heat into the surrounding area. The burning fuel creates heat, smoke, carbon dioxide, and water vapour. The heat escapes through the chimney at the top, warming the nearby area. Due to this design, smudge pots can heat whole areas with relatively little fuel.

The standard smudge pot can heat an area with a radius of about 15 feet. However, when used for agricultural purposes, where the goal is to keep the air above freezing, a smudge pot can effectively heat a larger area with a radius of up to 20-30 feet. This increased radius is influenced by factors such as the openness of the regulator, the type of fuel used, the return pipe design, and the outdoor temperature.

The effectiveness of smudge pots in heating larger areas is evident in their historical use in orchards and vineyards. For example, during the winter of 1932-1933, the Redlands district in California utilised 462,000 orchard heaters, demonstrating the ability of smudge pots to generate substantial heat across extensive areas.

They can run for 1.5-2 hours per gallon of diesel

A smudge pot is an oil-burning device used to prevent frost on fruit trees. It creates heat, smoke, carbon dioxide, and water vapour. They are also known as choofers in Australia, due to the noise they make when lit: "choofa choofa choofa".

Smudge pots are fuelled by liquid fuel, such as kerosene, diesel, or used cooking oil. They can also burn used oil, such as waste synthetic gear oil, used diesel oil, or used peanut oil. However, it is important to ensure that there is no water in the fuel, as this can be dangerous.

The amount of time a smudge pot can run depends on various factors, including outside temperature, how open the regulator is, the type of fuel used, and elevation. On average, a smudge pot can run for 1.5-2 hours per gallon of diesel fuel, with two holes open. They hold 7-8 gallons of fuel and are recommended to be started with at least 5 gallons, but preferably 7 gallons for the best results.

Smudge pots are ignited when the air temperature reaches 29 degrees Fahrenheit (-2 degrees Celsius). For each additional degree drop, another hole is opened on the control cap ("draft regulator"). Below 25 degrees Fahrenheit, no more adjustments can be made to enhance the heating effects.

Smudge pots were commonly used for seven decades, particularly in areas with citrus groves and vineyards, such as California. However, their use declined in the 1970s due to rising fuel costs and environmental concerns. Today, they are primarily used for agricultural, industrial, and farm purposes, as well as for camping and backyard heating.

They hold 7-8 gallons of fuel

A smudge pot, also known as a choofa or orchard heater, is an oil-burning device used to prevent frost on fruit trees. It is placed between trees in an orchard and creates heat, smoke, carbon dioxide, and water vapour.

Smudge pots hold 7-8 gallons of fuel and can burn almost any combustible liquid fuel, including kerosene, diesel, used sump oil, and even used cooking oil. However, it is important to ensure that there is no water in the fuel as this can be dangerous. The amount of fuel used depends on various factors such as outside temperature, how open the regulator is, the type of fuel used, and elevation. With diesel fuel, a smudge pot will typically run for 1.5-2 hours per gallon with two holes open on the regulator cap.

To fill a smudge pot, remove the regulator cap and pour in the fuel. To refill, ensure the smudge pot is turned off and cooled down, which usually takes around 45 minutes. Then, close the regulator and lid at the top of the stack before removing the regulator cap and pouring in the fuel.

Smudge pots are ignited when the air temperature reaches 29 degrees Fahrenheit (-2 degrees Celsius). For each additional degree drop, another hole is opened on the control cap to increase the heating effect. Below 25 degrees Fahrenheit, no further adjustments can be made to enhance the heat.

Smudge pots can be used for camping and hunting

Smudge pots, also known as choofas or orchard heaters, are oil-burning devices used to generate heat, smoke, carbon dioxide, and water vapour. They are typically used to protect crops from frost damage and to provide warmth in outdoor settings such as campgrounds. While they are not recommended as campfire replacements, here are some ways you can use smudge pots for camping and hunting:

Camping

Smudge pots can be a valuable source of heat for campers, especially when camping in colder climates. With the ability to burn different types of liquid fuel, including diesel, kerosene, and cooking oil, campers can stay warm for hours. It is important to note that smudge pots should only be used in well-ventilated areas due to the production of dangerous gases. Additionally, ensure that there is no water in the fuel as this can be extremely dangerous.

Hunting

Hunters can also benefit from using smudge pots, especially in cold weather conditions. By placing a smudge pot beneath a tree or in a concealed area, hunters can stay warm while waiting for their prey. The smoke produced by the smudge pot can also help to conceal their presence, as it did during wartime. The smoke creates a barrier that can block the view of the target, providing an element of surprise for hunters.

Other Outdoor Activities

Smudge pots are versatile and can be utilised for various outdoor activities beyond camping and hunting. For example, they can be used as a heat source when stargazing, fishing, or simply enjoying a bonfire with friends. Their ability to burn different types of fuel makes them convenient for extended periods outdoors.

It is important to note that smudge pots should always be used with caution and in accordance with safety guidelines. They produce high temperatures and dangerous gases, so adequate ventilation and proper handling are crucial to prevent accidents. Always refer to the instructions provided with your smudge pot and exercise caution when using any heating device outdoors.

Frequently asked questions