diff --git a/plugin/fugitive.vim b/plugin/fugitive.vim
index 13efb30..913f91f 100644
--- a/plugin/fugitive.vim
+++ b/plugin/fugitive.vim
@@ -241,7 +241,7 @@ augroup fugitive
   autocmd!
   autocmd BufNewFile,BufReadPost * call fugitive#detect(expand('%:p'))
   autocmd FileType           netrw call fugitive#detect(expand('%:p'))
-  autocmd User NERDTreeInit,NERDTreeNewRoot call fugitive#detect(b:NERDTreeRoot.path.str())
+  autocmd User NERDTreeInit,NERDTreeNewRoot call fugitive#detect(b:NERDTree.root.path.str())
   autocmd VimEnter * if expand('<amatch>')==''|call fugitive#detect(getcwd())|endif
   autocmd CmdWinEnter * call fugitive#detect(expand('#:p'))
   autocmd BufWinLeave * execute getwinvar(+bufwinnr(+expand('<abuf>')), 'fugitive_leave')