A change of state of weed seeds to having reduced germination viability in one minute by illuminating a seed in a processing theater to achieve at least one of 0.66 J/cm2 cumulative illumination energy, and 0.06 W/cm2 irradiance, of at least one of an Indigo Region Illumination Distribution (IRID), and Medium Wavelength Infrared (MWIR) radiation, preferably 2-8 microns, with no high energy transfers, scalding, heat shock, cooking or incineration. The MWIR radiation from heated borosilicate glass or glass powder at just under 500 C offered a peak MWIR emission of 3.75 microns, and was unexpectedly effective, and can be used in a radiant and transmissive weed seed accumulator transport belt. The process can be incorporated into a harvester combine to convert a tailings flow prior to discharge on an agricultural field. An illuminated harvest combine using an illuminator according to the invention allows reduction of the weed seed bank.