Thursday, October 19, 2006


I'm on a committee at work that is developing a plan to weed our library's collection of about 300,000 or so volumes. We need a systematic weeding program because we're running out of space. But besides opening up shelf space for new and more relevant library resources, a well weeded collection also can increase circulation. After all, with all the older, unusable things removed from the mix, it's easier to find the good stuff.

It goes without saying, but librarians don't like to throw books away. However, if a librarian takes a reasonable 20 minutes evaluating each volume (checking core lists, bibliographies, total copies in WorldCat, etc.), he or she will need at least 11.5 years. There must be a faster way.

There is! As a undergraduate liberal arts college, our primary weeding criterion can be use. Since my college is not a major research library, there isn't an expectation that we'll keep everything. As such, we librarians simply need to determine what books are being used, and withdraw the rest. And there will be evidence of such use on the date due slip or in the library system.

Also, using use as the primary criterion, we librarians avoid the problem that is encountered when using publication date to evaluate books: accidentally weeding those classics in a discipline published years ago. If a work is truly a classic, one would hope that faculty and students are using it!

We knew that we want to weed at least 10% of our collection, but we needed to determine a definition of "use" for our collection so removal at the shelves can be fast and efficient. So, we selected a statistically significant sample of 500 books (+/- 4.3% error, 95% confidence level). We recorded each book's last checkout date. We discovered that the bottom 10% of our collection last circulated before 1983. If the committee settles on the 10% figure, we'll be able to use this date as our test for each volume.

Yes, the system is not perfect: What about those books that were purchased 5 years ago but have not circulated? What about books in series, where one book was loaned, but none of the others? Or what about books that are used in-house and are never stamped with a due date? What about the books everyone is checking out, but are simply out of date?

Weeding is not perfect; accidents will be made. But a vast majority of things removed are never needed again. And more shelf space and an increase in general circulation are definite benefits.

We haven't started withdrawing anything yet. We just finished our sample and are trying to decide if we want to weed 5%, 10%, 15%, or all the way up to 30% of our collection. Whatever we decide, we have data to let us know when that bottom 5 or 20% last circulated, and at the same time have a convenient rule that staff can apply at the shelf to decrease the time agonizing over individual titles and increase the time we spend providing service at the reference desk, teaching in the classroom, or selecting new relevant information resources. Needless to say, we are excited to begin!

NOTE: For those of you who know where I work, our committee's work is in progress and our plan has yet to be approved by our library's faculty. Thus, the details described here are unofficial and are subject to change!


Barbara said...

We need to do more weeding, too - so I'll be watching your experiment with interest. This seems to me a huge and largely neglected aspect of academic librarianship. If we were to put a price on the space given to books that aren't used, or consider the value of space that could be recovered through weeding, we might take it more seriously.

Why is it so much easier to add a new book than it is to get rid of an old book? I have a feeling those new books would actually get used more if they weren't surrounded by out-of-date books!

On the other hand, I sometimes think public libraries are too quick to toss books, especially when I'm trying to go back and read books in a series or find earlier books by an author I'm just discovering.

Rudy said...

Hi Alec!
We just started weeding, but not as scientifically as your library. We are also a primarily undergrad liberal arts college, and haven’t weeded in over 40 years...

We have a great collection development policy, very concise and clear, and have used it as our primary guideline, along with circulation data.

I'm finding it a fascinating process; it really ties together all my various hats. I'm learning deeply about our collection, and about our curriculum (we are weeding across all areas, not just our own areas as selectors), and finding resources that I will talk to students and faculty about in relation to instruction, and from the reference desk. I’m really enjoying it.

I'm not prone to tossing away books, and I find myself swinging between two poles while weeding. Pole one: it's from the 60s (or 50s, or 40s...) and hasn’t circ’ed since the 80s, so it's easy to pull.... then, I realize that 1990 was 15 years ago, and have to fight the urge to pull everything, and leave the shelves stripped bare! (it may sound like our books don’t circulate, but we have a very small student body and one of the highest circulation rates in our very large system. Just not s high in the areas I;m currently weeding…)

At which point, pole two swings into being (a far more philosophical pole): what does it mean to be a well rounded library, to have a collection that supports student research more broadly than just strictly via curricular needs? What can I do, as an instructor and a reference librarian, to promote use of our books? And then, I leave what I comfortably can on the shelves, curse the budget, and make copious notes to selectors about my urge to decimate a particular area, and that it really needs to be updated.

The real peace of the project is that this is just round one, and we will be integrating weeding into the daily life of the library ion an ongoing basis. We expect Pass One to take five years, but then Pass Two will begin, and I suspect that Pass Two (and three, and four…) will be a much more difficult go, with much more gut-wrangling over appropriate material per our policies and interests…

Have fun with the weeding, and I hope to hear how it strikes you!