SPOKANE, Wash. — While fall doesn’t officially arrive for another week, some trees across Spokane are already displaying their autumn colors in what arborists describe as an unusual but not alarming early shift.
The early color change stems from two primary factors: reduced daylight and an extended period of intense summer heat. As days grow shorter, trees receive less light, triggering the breakdown of chlorophyll—the pigment that gives leaves their green color and enables trees to convert sunlight into energy. When chlorophyll fades, the natural yellow and orange pigments beneath become visible.
However, the shortened days alone don’t fully explain this year’s early transformation. Tim Kolhauff, an arborist, points to the summer conditions as a significant contributor to the accelerated change…