gistfile1.txt

//Setup -> Customize -> Chatter -> Feed tracking
//Enable feed tracking on TaskRay History, TaskRay Project Notification, TaskRay Task Notification, and TaskRay View Project objects

List<TASKRAY__trHistory__Feed> historyFeed = [SELECT Id FROM TASKRAY__trHistory__Feed];
delete historyFeed;

List<TASKRAY__trTaskNotification__Feed> taskNotificationFeed = [SELECT Id FROM TASKRAY__trTaskNotification__Feed];
delete taskNotificationFeed;

List<TASKRAY__trProjectNotification__Feed> projectNotificationFeed = [SELECT Id FROM TASKRAY__trProjectNotification__Feed];
delete projectNotificationFeed;

List<TASKRAY__ViewProjectTasks__Feed> taskViewFeed = [SELECT Id FROM TASKRAY__ViewProjectTasks__Feed];
delete taskViewFeed;

//Can reuse for other backend taskray objects.
//Be wary of deleting feeds on objects that matter, like TASKRAY__Project_Task__c