Melissa Joy Dietzel, 22, was living in St Ives on Sydney's north shore on a work visa and had been employed as a live-in nanny.

Her decomposing body was found by a council worker 10 metres up a tree next to an apartment block in Prince Lane, a small residential lane in Randwick, on January 12.

Police, who discovered her identity through dental records, are not treating her death as suspicious. They added that she had not been living in the tree and was not homeless.

Ms Dietzel, from Redlands in California, travelled to Sydney in October or November after studying elementary education at Brigham Young University in Utah, her friend, who asked to remain anonymous, said.

''She was big about the outdoors so she was stoked about being [in Australia]. She went to the national parks a lot.''

Ms Dietzel came from a large family - with eight or nine siblings - and was known in college for her bubbly nature, the friend said.

''She was the one that cheered everyone up and talked to everyone. Everybody remembers her for her hugs. Her laugh was infectious. She had a laugh that made everybody laugh - and you would forget about your problems.''

The friend said Ms Dietzel had been working as a nanny in Sydney but had been let go by the family who employed her.

On Facebook, Ms Dietzel's friends paid tribute to her.

"She said hi to me everyday of school my freshman year, and she always made me smile when I was having a horrid day," one friend wrote, adding: "She also gave fabulous hugs. That's mostly what I remember about her, but sometimes it's the little things that matter the most."

Her family in the US said she had been missing for more than a month when her body was found.

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