Abstract: Microwave transmitters generate electromagnetic energy at a desired frequency in the range of from 300 MHz to 300 GHz. Energy derived from the microwave transmitters is coupled into a waveguide for transmission to an energy radiator coupled to the waveguide. The energy radiator, waveguide and microwave transmitters are vehicle mounted such that the radiator is made to pass over areas in which it is desired to control vegetation. Vegetation, including seeds, in the path of energy emitting from the radiator absorbs the energy from the field resulting in internal changes in the plant or seed causing death or debilitation of the vegetation or seed.