Spectral measurements of the light emitted from a beam plasma discharge (BPD) in nitrogen show an abrupt increase in the ratio of N2 first positive emissions to the N2+ first negative emissions (red/blue ratio) at the onset of BPD. However, at beam currents substantially above BPD threshold, the red/blue ratio reverts to that produced by the beam itself (pre-BPD). This is interpreted as the appearance, at BPD onset, of a large suprathermal electron population, followed by a hardening of the suprathermal energy spectrum at higher beam currents. The new results are used to interpret previous ''white-light'' video images of BPD experiments. It is concluded that even larger red/blue ratios may occur at lower pressures and that a pre-BPD glow associated with radio-frequency emissions at the upper hybrid frequency is produced by a softer electron population than that occurring in BPD. In addition to the red/blue ratio, it was found that the ratio of the intensities of the 4--1 band and the 6--3 band of the first positive emissions varies systematically with beam current. The overall behavior is similar to that of the red/blue ratio-an abrupt increase followed by a steady decrease to the pre-BPD level. But the detailed dependence of the two ratios on current is different. ¿ American Geophysical Union 1988