A characteristic of well-flushed, properly dried, and cured cannabis flower that produces a clean white or very light grey ash when smoked, generally considered an indicator of quality and clean-burning properties.
Mr. Q observes 'immediately beautiful white ash' upon lighting the joint, and attributes it partly to good drying, curing, and potentially clean nutrient practices. He notes nobody in the group of three is coughing, calling it 'very clean burning.'