A boom structure for spraying or spreading including two side poles each formed of at least one segment, each segment or at least one of the segments of each side pole being composed of an assembly of elongated elements including, firstly, a top longitudinal tube, secondly, at least one bottom longitudinal tube and, lastly, bracing elements, forming tie rods and bridging pieces, extending between the top tube and at least one bottom tube, connecting them. A boom structure wherein each longitudinal tube has at least one radial protuberance, shaped in the longitudinal direction of the relevant tube, and including several openings spaced along the tube, each one constituting a site for securing an end of at least one bracing element.
