"A soldier correspondent who went by the initials W.K.. riding with Jenkins; command, reported to the Richmond Inquirer that the Rebel troopers had appropriates "many 'contrabands' and fine horses." Perhaps more chilling were the words penned by a Confederate officer named William S. Christian: "We took a lot of negroes yesterday...I was offered by choice but as I could not get them back home I would not take them" - "Gettysburg: A Testing of Courage" by Noah Andre Trudeau, p. 79.
While campaigning in Pennsylvania the confederate army took everything edible and anything not nailed down that could be of use to the army. That included every black man they could get their hands on.
It's called "foraging". Which is different from just burning everything down, in order to demoralize the population.