latex packages savetrees is persisting in my org-mode exporter

["Christopher W. Ryan" <cryan@binghamton.edu>]

I had been running Org mode version 7.9.3f, but I needed a feature only
available in version 8, so I upgraded, by downloading from the Org
website, and using comment characters in my .emacs file, like this:

;; Load org-mode
; (add-to-list 'load-path "c:/Org/org-7.9.3f/lisp")
; (add-to-list 'load-path "c:/Org/org-7.9.3f/contrib/lisp")
(add-to-list 'load-path "c:/Org/org-8.2.4/lisp")
(add-to-list 'load-path "c:/Org/org-8.2.4/contrib/lisp")
(require 'org)

Then I used it a few times to export a subtree from an org file,
exporting to pdf, using a latex package called savetrees.  I put this in
the subtree I was exporting:

** Review of assessment system, including instructions for bubble sheet
:PROPERTIES:
:EXPORT_FILE_NAME: ReviewAssessmentSystemWithPreceptors-12-02-2013
:EXPORT_TITLE: Review of our system for assessing student's clinical
performance
:EXPORT_LATEX_OPTIONS: \usepackage{enumitem}
:END:
#+latex_header: \usepackage{savetrees}

Now some features I need don't work--specifically, features from here:

http://orgmode.org/worg/org-tutorials/org-meeting-tasks.html

So I went back to Og 7.9.3f, or at least I thought I did, by changing my
.emacs to this:

;; Load org-mode
(add-to-list 'load-path "c:/Org/org-7.9.3f/lisp")
(add-to-list 'load-path "c:/Org/org-7.9.3f/contrib/lisp")
; (add-to-list 'load-path "c:/Org/org-8.2.4/lisp")
; (add-to-list 'load-path "c:/Org/org-8.2.4/contrib/lisp")
(require 'org)

But now every time I export a different subtree of that same org file, a
subtree that does not contain any mention of savetrees, to pdf, the
savetrees package is still loaded and used.  How do I stop it?

Thanks.

--Chris
-- 
Christopher W. Ryan, MD, MS
SUNY Upstate Medical University Clinical Campus at Binghamton
425 Robinson Street, Binghamton, NY  13904
cryanatbinghamtondotedu

"Once we recognize that we do not err out of laziness, stupidity, or
evil intent, we can liberate ourselves from the impossible burden of
trying to be permanently right. We can take seriously the proposition
that we could be in error, without deeming ourselves idiotic or
unworthy." [Karen Schulz, in Being Wrong: Adventures in the Margin of Error]