Trackbacks and Pingbacks haven’t shown me much value. In addition, they’re used for spammers to post tons of undesired comments on a WordPress site. This article from WPBeginner has very helpful information on how to disable and clean up all of the trackbacks and pingbacks: http://www.wpbeginner.com/wp-tutorials/how-to-disable-trackbacks-and-pings-on-existing-wordpress-posts/