GIT_WORK_TREE environment variable not working

What am I doing wrong here?

[ron@mickey:~/devel/gittest]$ pwd /Users/ron/devel/gittest [ron@mickey:~/devel/gittest]$ git status # On branch master # Untracked files: # (use "git add <file>..." to include in what will be committed) # # git/ nothing added to commit but untracked files present (use "git add" to track) [ron@mickey:~/devel/gittest]$ cd [ron@mickey:~]$ export GIT_WORK_TREE=/Users/ron/devel/gittest [ron@mickey:~]$ git status fatal: Not a git repository (or any of the parent directories): .git [ron@mickey:~]$ git status --work-tree=/Users/ron/devel/gittest fatal: Not a git repository (or any of the parent directories): .git [ron@mickey:~]$