Lee's original plan called for Hood and McLaws to attack in concert, but Longstreet held back McLaws while Hood's attack progressed. Around 5 p.m., Longstreet saw that Hood's division was reaching its limits and that the enemy to its front was fully engaged. He ordered McLaws to send in Kershaw's brigade, with Barksdale's to follow on the left, beginning the en echelon attack—one brigade after another in sequence—that would be used for the rest of the afternoon's attack. McLaws resented Longstreet's hands-on management of his brigades. Those brigades engaged in some of the bloodiest fighting of the battle: the Wheatfield and the Peach Orchard. Colonel Byron Root Pierce's 3rd Michigan Regiment, which was part of de Trobriand's brigade, engaged Kershaw's South Carolinian forces during the defense of Peach Orchard.