Residents of Melbourne send love letters to city's trees

In Shel Silverstein's 1964 children's book "The Giving Tree," he told the story of a tree that loved a little boy -- and now, for people who want to give back to trees, the city of Melbourne, Australia inadvertently came up with a way for us to show that we too love trees very, very much.

The city created an interactive forest map, showing each of the more than 70,000 trees across central Melbourne. Every tree has its very own identification number -- and it's own email address. This was for people to report things like broken branches. But what happened was something city officials never expected.

One city official told The Guardian that "instead of reporting problems with trees, people began writing letters about how much they love individual trees in the city."

One tree fan emailed their favorite tree, a golden elm, telling it to "keep up the good work," and another, a golden leaf elm, was told to "stay in good shape" by its number one fan who was moving abroad.

The program started in 2007, after nearly a decade of drought ravaged in southern Australia -- the worst ever on record -- which didn't even begin to ease up for much of the country until 2010. Once emails flooded in, city workers took it upon themselves to write back to tree lovers with messages of their own. Still, the city is hoping for a greener future. They hope to double the area covered by tree canopies by 2040, reducing carbon dioxide -- and giving residents some much-needed shade.

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