The paper investigates the ignition and burning mechanisms of live Norway spruce needles, focusing on Non-Destructive Evaluation (NDE) techniques to study fire behavior. A hybrid Schlieren-Infrared (IR) system was developed, allowing precise visualization of live fuel ignition. The combined approach revealed critical details like volatile ejection during ignition, which can alter flame behavior and heat nearby fuels. This phenomenon, unseen in dead fuels, leads to micro-explosions and flame deflections, enhancing heat transfer. The non-destructive methods (Schlieren and IR thermography) enabled detailed analysis without altering the sample, providing new insights into how live fuels support fire propagation despite high moisture content. These micro-explosions, visualized through Schlieren and IR, were crucial in preheating adjacent fuels through hot volatile jets and intermittent flame contact, which could lead to ignition. In summary, the paper's application of NDE techniques provided a novel approach to understanding forest fire dynamics, showing how live needles’ behavior differs significantly from dead fuels, particularly in their contribution to fire spread and micro-spotting phenomena.