Who Eucalyptized Southern California?

Although the orange and the palm loom large in Southern California's iconography, another imported tree -- the eucalyptus -- has been almost as prominent a feature of the region's landscape. Eucalypti grace parks and gardens and shade sidewalks and roadways. In many suburbs, long rows of the tree, planted long ago as windbreaks, betray the land's past use for citriculture.

But prior to the 1850s, not a single eucalyptus grew in California, which raises the question: how did this tree, an invader from an alien botanical world, come to tower over so much of the region's streets and green spaces? Who eucalyptized Southern California?

Native to Australia, eucalypts feature leathery leaves and flowers whose petals fuse together to form a cap. In fact, the name "eucalyptus" refers to this bud, deriving from Greek words meaning "well-covered." Botanists recognize more than 500 distinct species, but Southern California is best acquainted with one: eucalyptus globulus, also known as the blue gum.Eucalyptus globulus, indigenous to Tasmania and southeastern Australia, is instantly recognizable by its minty scent, shimmering leaves, and peeling bark.