What’s the Reason Behind Painting Trees White?

Many people notice trees with white-painted trunks and assume the color is decorative, but it actually serves an important functional purpose. The white coating is used by tree caretakers to protect trees from specific types of damage, especially during winter months.

While white paint has a protective role, other tree markings can indicate entirely different things. For example, orange spots often identify trees that are scheduled for removal, helping workers mark which ones need cutting. Purple paint, on the other hand, is widely used to show property boundaries or areas where trespassing is not allowed.

White paint, however, is applied for a reason unrelated to boundaries or removal. Its purpose is to prevent a type of winter injury called sunscald. Sunscald occurs when a tree’s bark warms up in the sunlight during cold months and then rapidly cools once the temperature drops at night.

This sudden temperature shift makes the bark expand and contract quickly, causing cracks that weaken the tree. Over time, these cracks can create entry points for pests and diseases, making the tree more vulnerable as it ages.

To prevent this, caretakers apply a thin layer of diluted white latex paint to the trunk. The white color reflects sunlight, reducing how much heat the bark absorbs during the day and helping stabilize its temperature. This simple step significantly lowers the risk of sudden temperature-related damage.

The paint mixture is typically half water and half latex paint, ensuring coverage without suffocating the bark. It only needs to be refreshed once a year. When you see a white-painted trunk, it signals proactive care—an easy yet effective way to protect the tree throughout harsh winter conditions.