A system and method of controlling self powered decorative devices using EMF emanating from, for example, a light string on a Christmas tree. The decorative devices sense the presence of EFM from the light string and actuate in response thereto and turn off when the field disappears, thereby saving energy. In an alternate embodiment, the EMF source is capable of modulation and the slave decorations are coded and tuned to specific EMF characteristics, such as frequency. The master EMF source transmits the EMF of different characteristic thereby causing the coded slave decorations to operate in a synchronized matter. The system may also be responsive to music or other inputs to create special decorative effects.