Many Californians know eucalyptus trees were brought to California in the late 1800s for lumber. They were planted extensively from the 1870s through the early 1900s. In the 1950s you could drive the length of the “Great State of California” and pretty much not lose site of a eucalyptus tree.
These Australian natives turned out to be bad lumber, not even suitable for fence posts and not great firewood either being so oily and resinous. Today, the millions of primarily blue gum eucalyptus that remain are generally agreed to be an ecological disaster. Relative to the native woodlands they replaced, they are largely sterile ecologically and have an increased fire hazard.
As a Californian I grew up on this story, and as a nature lover, duly hated eucalyptus. I was thrilled when an early job I had was eucalyptus eradication and reforestation with native oaks. What I didn’t know was that prior to the lumber planting frenzy, eucalyptus was planted as a cure to malaria.
Photo by Wikiwatcher1.
California actually did have problems with malaria in the 19th century, especially in Sacramento Valley and Kern County. The role of the mosquito in the disease’s spread was still unknown and it was thought by medical professionals of the day that the pungent, volatile oils disinfected the air and soil. It was the “fever-destroying tree.”
One example of proof was a California farmer who planted hundreds of blue gum next to a family of workers living in a swampy area but did not plant the trees by a second family living in a similarly swampy area. The family near the trees stayed well, while the other one had many cases of malaria.
In 1900, the connection with malaria and mosquitos was made and it was clear that if eucalyptus helped reduce malaria it was because they consumed a lot of water and helped dry up swamps.
Further Information
Jared Farmer, History Professor at Stony Brook University, has recently done some great pieces on the history of eucalyptus trees in California:
Gone Native: California’s Love-Hate Relationship with Eucalyptus Trees
The Rise and Fall of the Gum Tree. How California Adapted—and Disowned—Eucalyptus
Sources Used
- The Eucalyptus of California. Section Two: Physical Properties and Uses. Robert L. Santos. 1997. Alley-Cass Publications
Denair, California. 1997. http://wwwlibrary.csustan.edu/bsantos/section2.htm#The%20Eucalyptus%20of%20California - Gone Native: California's Love-Hate Relationship with Eucalyptus Trees. Jared Farmer. Academia.edu Website. http://www.academia.edu/322875/Gone_Native_Californias_Love-Hate_Relationship_with_Eucalyptus_Trees"
- Monterey Bay Area: Natural History and Cultural Imprints, Second Edition. Burton Le Roy Gordon. Boxwood Press; 1977.
- The Eucalyptus of California. Section Two: Physical Properties and Uses. Robert L. Santos. 1997. Alley-Cass Publications
I think all over the place, but usually in the warmer states as they have a low tolerance for cold weather. But the paper industry is testing out eucalyptus trees engineered to withstand chilly temperatures. The industry thinks that this can help them grow more trees faster and in a smaller area, helping to conserve already existing forests.
The larvicidal properties suggest that the essential oil of plant is a potential source of valuable larvicidal compounds against malaria vector and can be used as an alternative to synthetic insecticides.