The Dangers of Winter SunScald & How to Prevent It

Winter is beautiful but also harsh on trees. One serious problem is winter sunscald. Sunscald damages tree bark, weakens trees, and can introduce pests and disease. At Frontier Tree Service, we can help your landscape stay healthy with expert winter tree care.

Here is the lowdown on sunscald, how it damages trees, and how to protect your trees from sunscald.

What is Winter Sunscald?

Winter sunscald, also called southwest injury, damages the bark and underlying wood. In fluctuating winter temperatures, sunlight warms tree bark on the south or southwest side of the tree during the day, enough to reactivate the dormant cells. In the late night hours, the temperatures plunge and those cells freeze and die.

Cracked, sunken, or peeling bark weakens the tree’s defenses and leaves the tree open to disease and decay. Sunscald is not often noticed until spring or early summer, when temperatures start to rise and damage is visible.

Thin-Barked Trees

Trees with thin bark are more susceptible to sunscald. Species to watch for include:

• Maples (Acer)
• Linden (Tilia)
• Crabapple and fruit trees (Malus, cherry, plum)
• Honeylocust
• Aspen and poplars

Young and Newly Planted Trees

Trees in their first few years after planting are especially at risk. Young trees are more sensitive to winter temperature fluctuations. Their bark has not fully matured.

Trees with Full Sun Exposure

Trees in open areas with unobstructed southern or southwestern exposure get the most sun in winter afternoons when sunscald risk is the highest.

Winter Sunscald: Serious Damage, Not Just Cosmetic

Sunscald does more than mar the bark. The cracking and damage can:

• Expose inner wood to insects and pathogens
• Allow moisture and decay organisms to penetrate
• Interrupt nutrient and water transport
• Damage the health of the tree in the long term

Sunscald is a serious health issue for trees. Without treatment, it can shorten the life of a tree, and lead to expensive treatment or removal.

Protect Your Trees: Tree Wraps & Natural Barriers

Tree wraps and trunk guards provide a physical shield that can help protect trees from sunscald.

Why Tree Wraps Work

Tree wraps or trunk guards:

• Reflect the intense winter sunlight, preventing daytime warming
• Reduce fluctuating temperatures that damage cells
• Shield bark from cracking and splitting in freeze/thaw cycles

Best Practices for Using Tree Wraps and Trunk Guards

• Apply wraps and trunk guards in late fall, once dormancy begins
• Wrap from the base up to the lowest branches
• Choose light-colored, breathable material that reflects heat
• Remove the wraps in early spring to prevent moisture buildup and pests

Natural Barriers and Landscape Strategies

Protect tree bark with natural barriers:

• Shade trees from afternoon sun by planting shrubs
• Mulch around the base to buffer soil temperature
• Use fencing or windbreaks to temper ambient temperatures

Winter Tree Care: Challenges Beyond Sunscald

Sunscald is just one of many winter tree care challenges. In addition to sunscald, our pros can check trees in winter for:

• Frost cracks and other structural weaknesses
• Broken or damaged branches
• Early indicators of disease
• Potential hazards before spring growth begins

Winter is not the “off-season” for tree care. It’s the perfect time for preventative maintenance and risk assessment.

At Frontier Tree Service, our certified arborists are trained to diagnose sunscald risks and provide tailored solutions to protect your trees throughout the winter months. Whether you need:

• Professional winter tree inspections
• Tree wrap installation
• Seasonal pruning and pruning for winter health
• Comprehensive winter tree care plans

Schedule your winter tree inspection with Frontier Tree Service today and give your trees the protection they deserve. Call us or request an estimate online now and don’t wait for damage to appear.

Protect your investment. Preserve your landscape. Partner with Frontier Tree Service.

Categorized in: Winter Preperation