Expert reveals dark truth behind seemingly harmless tree species found all over California: 'It's our job to remove the mess that we created'

Botanist Jessie Dickson (@sacramentofoodforest) provided a tour of eucalyptus trees in California — and argued why they're terrible for the environment there.

"Eucalyptus trees are one of the worst invasive species in California and are taking over native land that used to be old growth redwood forest," Dickson wrote in the video caption on Instagram. "... Eucalyptus trees fall easy with shallow roots that injure people every winter."

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A post shared by Jessie Dickson🌱 (@sacramentofoodforest)

Worse still, he noted, the oil from Tasmanian blue gum eucalyptus kills native plants and is highly flammable, making it a wildfire threat.

The history behind the plant is particularly interesting. Dickson dives into how eucalyptus was originally brought to California as a fast-growing cash crop, in part to make up for the absence of redwoods that had already been decimated. It turned out that eucalyptus wood was unsuitable for lumber.

The irony didn't stop there, though, according to the post. Dickson suggests that the flammability of eucalyptus oil may have contributed to burning down the home of one early popularizer of the plant: Jack London. The story goes that a fire happened days before London was due to move in. However, other sources, such as a 1996 New York Times article and a 2013 piece in California's The Press Democrat, suggest the exact reasons for the fire are mysterious and complex.

Invasive species regularly follow a playbook. They're brought by people into a new area where they don't have to deal with the checks and balances they evolved with. That allows them to spread unimpeded into a new territory. This monopoly on territory and food pushes out other species and ruins vital biodiversity. Studies suggest invasives are the source of hundreds of billions of dollars in economic costs worldwide.

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Dickson used the video to promote native species and to end the proliferation of eucalyptus. Planting and promoting native species can reduce the water (and money) used for landscaping. It can also help the health of natural habitats.

"Eucalyptus is only here because of humans, so it's our job to remove the mess that we created," Dickson says. Instagram community members were wholly on board with his perspective.

"Thanks for doing the work and sharing what you learn. It's all out there not all see it!!" said one viewer.

"You can't just cut them down either. The stump needs to be entirely removed," said another. "I've seen whole trees grow back from just a ground level stump. Stuff is scary hardy. The oils are antimicrobial as well so take WAYYY longer to break down than other trees."