Smudge pots are old-style frost protection devices used in fruit orchards, especially citrus. They burn fuel to create heat and smoke that helps reduce heat loss from trees during cold snaps, thereby lowering the risk of frost damage. They have largely fallen out of use due to pollution and the availability of cleaner frost-protection methods. Key points:

• Purpose: Prevent frost damage to fruit trees by creating a warm blanket of heat and smoke between trees.
• How they work: A fuel-burning pot sits among the trees; burning oil (often kerosene) produces heat, smoke, carbon dioxide, and water vapor, which helps decelerate daytime cooling and delay ice formation on blossoms and foliage.
• Modern context: Many regions have moved away from smudge pots due to air pollution and fire hazards. Alternatives include wind machines, sprinkler irrigation, infrared heaters, or covered agriculture (e.g., frost cloths) and other smokeless burners using cleaner fuels.

If you want, I can tailor this to a specific crop, region, or historical period, or compare smudge pots to modern frost-protection techniques.