You’ve seen them—trees with trunks painted a bright, clean white, standing out against winter’s bare landscape. At first glance, it might look like decoration or even vandalism. But this practice is actually a centuries-old agricultural technique with a vital purpose: protecting trees from sunscald.
Far from being random, that white paint is a lifesaving shield—a simple yet brilliant solution to a hidden threat that damages thousands of trees each winter.
❄️ What Is Sunscald—and Why It’s Dangerous
In winter, trees face a silent killer: dramatic temperature swings.
- On sunny days, dark bark absorbs heat, warming the trunk and causing cells to become active.
- When the sun sets or clouds roll in, temperatures plummet—sometimes by 50°F+ in hours.
- The sudden freeze causes bark to crack, split, or peel, exposing tender inner tissue to disease, pests, and decay.
This damage—called sunscald or southwest injury (since it most often affects the sun-facing side)—can weaken or even kill young or thin-barked trees like:
- Maples
- Birches
- Fruit trees (apple, cherry, peach)
- Ash and honey locust
🌳 Fun fact: Sunscald is most common on newly planted trees, which haven’t yet developed thick, protective bark.
🎨 How White Paint Saves the Day
The solution? Reflective white paint—acting as “sunscreen” for trees.
- White reflects sunlight, preventing the bark from overheating during the day.
- This minimizes temperature swings, keeping the trunk stable and intact.
- Unlike dark bark, a white-coated trunk stays cool—even in full winter sun.
What Kind of Paint?
