A steam injection manifold assembly is mounted to a crop pick-up assembly and is provided with an elongate manifold disposed lengthwise of the pick-up assembly. A plurality of steam injection tubes are releasably mounted to the manifold to receive steam exiting through respective steam outlet openings provided in the manifold. In one embodiment the injection tubes are shaped similarly to tine stripper bands of the pick-up, and in another embodiment the injection tubes define the stripper bands of the pick-up.