DDL Collection Weeding Guidelines

Goal of Weeding

The basis of the DDL collection, as well as how it is developed and maintained, rests within its mission and the collection priorities as outlined in the DDL Collection Policy. A weeding plan is part of maintaining a library’s collection and is the periodic and continual evaluation of library resources with the goal of removing aged, obsolete, non-relevant, inaccessible, broken, unusable or out of scope materials from the library. Weeding ensures that library materials are useful, attractive, beneficial and accessible to DDL users. Good weeding makes a library more useful and user-friendly. Weeding is a natural part of maintaining a healthy library. 

Criteria for Weeding Resources

  • URL to the resource is broken and new URL is not easily discoverable
  • URLs and links within the resource are broken; the resource cannot be fully used 
  • Format of the resource is out of date and not usable on digital devices
  • Scientific or other content is out of date or no longer accurate *
  • Resource lacks of robustness as an educational resource (e.g., resource is difficult to interact/navigate, media format is dated or requires software that is no longer available) 
  • Purpose of resource is unclear or resource is not intended for educational use (e.g., conference proceedings, blog entries, newsletter articles)
  • Resource is not directly accessible (e.g. subscription cost, goes to a landing page where it is difficult to get to the actual resource) 
  • Original resource is available elsewhere in DDL from the original creator and is redundant
  • Resource does not meet DDL criteria as an open educational resource (OER)

The DDL Collection Policy, DDL Resource Priorities & Selection Guidelines, and DDL Resource Quality Checklist provide additional criteria for understanding the value of resources to the DDL and should be continuously consulted during the weeding process.

Evaluation of Resources

The weeding evaluation process will be undertaken by the library Content Editor who is familiar with the DDL collection and understand the goals of the library. The criteria for weeding resources, outlined above, along with the DDL Collection Policy, DDL Resource Priorities & Selection Guidelines, and DDL Resource Quality Checklist provide the guidelines for determining whether a resource belongs in DDL or should be weeded. 

When a reviewer suggests a resource is weeded, the item will be marked with a “Review” status. Final deaccessioning of resources from the DDL collection will be approved by the DDL Library Manager and, when approved, the status of the resource will be changed to “Deaccessioned” and no longer display in the library.

Related Documents:
DDL Collection Policy
DDL Resource Priorities & Selection Guidelines
DDL Resource Quality Checklist
DDL About Us

* Important note: For science subjects such as medicine, no information is considered better than outdated or inaccurate information. In other science areas (e.g. physics, astronomy) information dates rapidly, and weeding must be aggressive with anything over five years old examined for accuracy and deaccessioned, as necessary. Other areas such as mathematics change slowly, and weeding will be less aggressive.