American Battlefield Trust’s map of the Battle of Gettysburg - The Wheatfield and Peach Orchard
Without orders, Union III Corps commander Gen. Daniel Sickles advanced his troops off Cemetery Ridge to a position he deemed to be ground better suited for defense: the elevated, open plateau around farmer Joseph Sherfy’s peach orchard on the Emmitsburg Road. Sickles’ thin line stretched nearly a mile from the Rogers farm to Devil’s Den.
When Longstreet launched his attack, Joseph Kershaw’s South Carolina men from McLaws’ division pushed east across the George Rose farm. Kershaw’s regiments split and were forced to give attention to Union infantry and artillery in the orchard on their left flank as well as regiments posted on a boulder-covered hill in their front. After Kershaw’s men advanced, the Mississippians under William Barksdale moved forward.
Five volunteer batteries from the Artillery Reserve under Freeman McGilvery augmented Sickles’ regiments and formed a solid line of cannon along the road facing south toward the Rose farm. McGilvery’s batteries tore into the flanks of Kershaw’s men as they moved across their front.
In the Wheatfield area, only the III Corps brigade of Phillipe Regis de Trobriand held the ground, connected tenuously to John H. H. Ward’s brigade at Devil’s Den. George Winslow’s New York battery from the III Corps and two regiments from George Burling’s brigade supported de Trobriand’s men. The 17th Maine, placed behind a stone wall on the south edge of the field, held back successive attacks from George T. Anderson’s Georgia regiments. Around 5:00pm the Fifth Corps brigades of William Tilton and Jacob Sweitzer arrived to help de Trobriand, followed shortly by the II Corps division of John Caldwell.