Criteria for Weeding:
CONDITION - Materials in poor condition are prime candidates for replacement. Weed items which have the following defects:
CONTENT – Books may be in excellent physical condition but contain inaccurate information or be presented in such a way as to warrant weeding. Weed based on the following criteria:
USE - Inventory reports on selected areas that show the frequency of circulation and/or the most recent circulation may be generated from data collected by the ILS. Generally, items that have not circulated for three years and are not needed for reference should be evaluated for discard. In smaller, more crowded collections or with more popular formats, such as DVD, it may be more useful to consider items that have not circulated in the last year as possible candidates for withdrawal.
When to weed:
Ideally, weeding is an ongoing activity. This is easiest to achieve when weeding for condition. Clerical and page staff can be trained to set aside materials in poor condition for consideration by the librarian.
When weeding for content, developing a regular schedule is helpful. One possibility is to have an actual weeding calendar. An annual or multi-year cycle may be created that ensures that all areas of the collection are weeded on a regular basis.
Another option is to identify certain topics or formats that can be weeded following periods of peak popularity. For example, books on Christmas, Hanukkah and Kwanzaa could be weeded each January on the assumption that any titles not popular during the current season are unlikely to develop additional appeal by sitting on a shelf for a year.
Another possibility is to link weeding to other activities. For example, weeding is a natural accompaniment to selection. When selecting materials for a specific area review the materials on the subject that are currently owned and identify any that may be replaced by the new titles.
How to weed:
Examine the library's Collection Development Policy. Consider the library’s mission and the demographics of your community. Examine usage statistics, if possible. Consult and use the weeding guidelines. Involve your staff and work as a team.
How much to weed:
In locations where collections are already at optimum levels, it’s necessary to weed as many items as are received throughout the year. This keeps the collection size constant and provides for ease of use and sufficient display opportunities. When space is not an issue, weed for content and condition.
From The Carnegie Library document on Collection Develoment.