EDC tracks the date of revision of publications and informs counties whether or not old copies should be kept. If a publication is simply reprinted or revised with no significant changes in content, no returns of the old version will be accepted. Look for those publications with an extension of .pdf. The site also has instructions on how to get the Acrobat Reader. A free printed catalog listing extension publications is available from the Extension Distribution Center.
Copies are free.
Ask for SP-21. The catalog is updated twice a year. These may be used at the author's discretion. If EDC or a department receives a letter requesting a cost publication and the remittance is not included, a form may be returned to the person. If a department chooses to mail a cost publication to a person in response to a question, the department must supply the cost publication from the author's discretionary supply or follow the procedure described previously.