A surgical stapling apparatus (10) including a releasable buttress material (24) includes a cartridge assembly (32), an anvil assembly (20), a knife (30), and a buttress material (24) . The cartridge assembly includes a plurality of staples (50) and a tissue contacting surface (23) defining staple retaining slots (52). The anvil assembly includes a tissue contacting surface defining staple pockets (68) for forming staples expelled from the staple retaining slots of the cartridge assembly. The knife is disposed within a knife slot (25) formed in the tissue contacting surface of the cartridge assembly. The buttress material includes at least one weld (40) joining the buttress material to the tissue contacting surface of the cartridge assembly. The at least one weld is positioned across the knife slot.
