From my initial look, I believe it is Wilcox's and Lang's skirmishers pushing forward.
Edmund Patterson writes that they succeeded in making them (Union skirmishers) withdraw some distance. This allowed them to occupy the Spangler barn "for some time", until they were driven back by Union artillery fire into the barn. Now unfortunately he doesn't state the time other than as soon as "our regiment got into position." Which could be as late as 10:00 am before they got deployed and pushed forward skirmishers. pg 115 "The Civil War Journal of Edmund DeWitt Patterson."
Major Danks of the 63rd PA, only said in his OR that the enemy made an appearance in our front that morning. But nothing about being pushed.
I don't believe Jerome is mentioning the reconnaissance that Berdan went on earlier in the day. By 1155, Lang and Wright's brigades have joined Wilcox in some of those woods. I am assuming he is speaking of H. Spangler woods, but even if he is speaking of Pitzer's woods, at that time the 8th and 10th Alabama are on the northern end of that woodlot. So the woods would be full of them.
Phil