Nanowire (NW) resonant nanoelectromechanical systems (NEMS) with integrated electronic signal transduction are attractive for realizing ultra-low-power nanomechanical radio-frequency (RF) signal processing. A major challenge lies in the high motional impedances of electrostatically-transduced high-frequency NW NEMS resonators. In this digest paper, we describe a technique for realizing oscillators that can achieve stable and low phase noise oscillations with such characteristic high motional impedances in NW NEMS. The technique is based on the basic theory of designing CMOS Pierce oscillators with low phase noise and low power consumption. We further design an oscillator with 1.5V power supply, which features a phase noise level of −104dBc/Hz at 10kHz offset from a 1GHz carrier, and consumes only 2.5μW power. Cadence circuit simulations on oscillator performance demonstrate the theoretical insights from this study may be important for designing oscillators based on challenging nanoresonators with high motional impedances.