desert ironwood

tree

Also known as: Olneya tesota, palo fierro

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July 17, 2026

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Desert ironwood (Olneya tesota) is a small leguminous tree native to the southwestern United States and Mexico. It is characterized by odd-pinnate leaves and purplish-white flowers. The wood of this tree is exceptionally dense, earning it the name "ironwood".12

This tree plays a vital role in the Sonoran Desert ecosystem, acting as a "nurse plant". It provides essential shade, forage, and nesting sites for animals, while also protecting smaller plants from harsh sun and frost. Native peoples have historically utilized desert ironwood for food and medicine. Desert ironwood trees can grow up to 45 feet tall and live for over 800 years.2

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Ironwood Forest National Monument
…preserves a significant stand of desert ironwood trees (Olneya tesota), a species endemic to the Sonoran Desert. The ironwood was named for the extreme density of its wood; it can reach 45 feet (14 metres) in height and live for more than 800 years. It serves as a “nurse plant,”…
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…preserves a significant stand of desert ironwood trees (Olneya tesota), a species endemic to the Sonoran Desert. The ironwood was named for the extreme density of its wood; it can reach 45 feet (14 metres) in height and live for more than 800 years. It serves as a “nurse plant,”…
Read More