a tagging attachment for a hay baler for automatically inserting an identification tag into a hay bale at a specified preselected location , includes a guide support member extending into the bale chamber for supporting a tag in a position in the chamber for being torn from a roll or strip of tags as the bale is being formed . the hay passing across the support engages and tears the tag from the tag strip . tags are selectively and intermittently advanced in response to a predetermined timing during the formation of the bale for precise location of the tag within the bale .