Native Plants

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Tuesday - August 09, 2011

From: Arcilla, CA
Region: California
Topic: Medicinal Plants, Herbs/Forbs, Shrubs
Title: What gives the Creosote bush its characteristic smell?
Answered by: Guy Thompson

QUESTION:

Good evening, Mr. Smarty Plants, There is a question which I would please like to ask regarding a plant called "Creosote Bush" (Larrea tridentata)- does it actually smell like the creosote preservative solution used to preserve railroad crossties and utility poles? Best regards,

ANSWER:

Indeed, the characteristic creosote smell emanating from the Larrea tridentata (Creosote bush) is caused by the same chemical compounds used for preserving crossties and utility poles. But don't worry, the bulk of wood-preservative compounds are derived mainly from coal and petroleum, not by grinding up acres of pretty Larrea. Creosote from Larrea gets its smell largely from phenolic compounds, such as cresol. This is also what you smell from wood preservatives. The phenolic compounds, along with a mixture of many other volatile oils (not necessarily the exact same ones found in coal and petroleum), evaporate readily into the air in tiny amounts, especially in warm weather. Rainfall seems to enhance the release of volatile oils from Larrea.

If the creosote smells "medicinal" to you, it did to many others in the past, and Larrea extracts have been used to treat various ailments. Mr. Smarty Plants urges you to resist the temptation.

From the Image Gallery

Creosote bush
Larrea tridentata