Abstract: A crop stalk guide cutterbar extension for use on a crop stalk guide attachment to a crop gathering header cutterbar includes a plurality of mounting bars, guide bars and braces which provide a plurality of assembled units for mounting to and forwardly of the crop stalk guide attachment. Each assembled unit of the extension is formed by one of the mounting bars, one of the guide bars and one of the braces. Each mounting bar is attached to and extends forwardly from a support framework of the crop stalk guide attachment and each guide bar overlies one mounting bar and has a forward end attached on a leading end of the mounting bar. The guide bar is supported by one of the braces disposed between the guide bar and corresponding mounting bar to extend inclined upwardly and rearwardly from the forward end to a rearward end overlying and spaced above a leading end of one of the guide plates of the crop stalk guide attachment.